Honors Chemistry Organic Chemistry Packet This packet will NOT be graded traditionally. All Answers are available to you. Your Teacher is available to you before school, lunch and after school with appointments. You are expected to keep up with the assigned pages. Quizzes will be given periodically covering assignments up to the assigned pages that day. Highlight ALL READINGS showing how molecules are named and made. The packet will be picked up and graded as follows: a) b) c) d) e) f) g) h) 2 points per page. Any missing or incorrect problems noticed on a page will result in zero points for that page. All problems marked NR-“no reaction” must have a valid written reason to explain the problem. Failure to give a reason for an NR will result in ZERO points for that page. When grading the packet ,the teacher will grade certain problems but will be looking for letter b) above. Follow directions on each page. Make note of any directions your teacher gives that may change the directions on the pages. Highlight things the teachers say you MUST KNOW. Each class period will be divided into the following: 1) Review and discussion of problems assigned the night before. 2) Introduction to new problems. 3) Time to work on new problems. Page 1 KEEP UP. DO NOT GET BEHIND ON THE ASSIGNED PAGES. Contents Organic Families and Functional Groups .................................................................................................... 5 ORGANIC FAMILIES 1 .................................................................................................................................. 6 ORGANIC FAMILIES 2 .................................................................................................................................. 7 Organic nomenclature part (1) ................................................................................................................... 8 ORGANIC NOMENCLATURE Part 2 .............................................................................................................. 9 Organic Nomenclature Part 3 ................................................................................................................... 10 3.4 Naming Alkanes .................................................................................................................................. 11 3.4 Naming Alkanes cont. ......................................................................................................................... 12 3.4 Naming Alkanes cont. ......................................................................................................................... 13 3.4 Naming Alkanes cont. ......................................................................................................................... 14 3.4 Naming Alkanes cont. ......................................................................................................................... 15 3.4 Naming Alkanes cont. ......................................................................................................................... 16 3.4 Practice Problems ............................................................................................................................... 17 Worksheet 3 Organic Nomenclature ........................................................................................................ 18 Identify all the functional groups.............................................................................................................. 19 Nomenclature Examples ........................................................................................................................... 20 Worksheet 4 Organic Nomenclature Part (II) .......................................................................................... 21 Naming Saturaded Hydrocarbons I ........................................................................................................... 22 Naming Saturaded Hydrocarbons II .......................................................................................................... 22 Formula Writing: Saturated Hydrocarbons.............................................................................................. 24 Naming Organic Functional Groups Form WS11.3.2A .............................................................................. 25 3.1 Functional Groups ............................................................................................................................... 26 3.1 Functional Groups ............................................................................................................................... 27 Recognizing Functional Groups................................................................................................................. 28 Recognizing Functional Groups cont. ...................................................................................................... 29 ALKANE NAMING: iso, neo, & cyclo ......................................................................................................... 30 Alkanes ...................................................................................................................................................... 31 Properties of Alkanes ................................................................................................................................ 32 PROPERTIES OF ALKANES REACTIONS ............................................................................................... 33 Organic Flowsheet .................................................................................................................................... 34 Alcohols and Grignard Reactions ........................................................................................................... 35 Mapping Multistep Synthesis 1 ............................................................................................................... 38 Mapping Multistep Synthesis 2 ............................................................................................................... 39 Page Organic Chemistry Multistep Synthesis .................................................................................................. 37 2 Organic Synthesis ...................................................................................................................................... 36 Nomenclature Exercise ............................................................................................................................. 40 Haloalkanes ............................................................................................................................................... 41 Haloalkanes cont....................................................................................................................................... 42 Reactions of haloalkanes .......................................................................................................................... 43 Chemistry Worksheet—Prepartions ......................................................................................................... 44 Alkenes...................................................................................................................................................... 45 Naming Alkynes and Dienes ..................................................................................................................... 46 FORMULA WRITING: ALKYNES AND DIENES ............................................................................................. 47 CHEMISTRY ............................................................................................................................................... 48 REACTIONS OF ALKENE AND ALKYNES...................................................................................................... 48 Markownikoff's Rule: ................................................................................................................................ 49 Markownikoff's rule cont.......................................................................................................................... 50 PROPERTIES OF ALKENES I ........................................................................................................................ 51 PROPERTIES OF ALKENES II ....................................................................................................................... 52 PROPERTIES OF ALKENES AND DIENES ..................................................................................................... 53 Organic Chemistry alkanes, alkenes, alkynes ........................................................................................... 54 Chemistry .................................................................................................................................................. 55 Organic Reaction ....................................................................................................................................... 55 Organic Chemistry Show the Predicted Products ................................................................................... 56 Organic Reactions Worksheet .................................................................................................................. 57 Predict Reactants: Complete the following processes ............................................................................ 58 Chemistry Multistep Synthesis ................................................................................................................ 59 ALCOHOLS ................................................................................................................................................. 60 NAMING ALCOHOLS ............................................................................................................................ 61 FORMULA WRITING: ALCOHOLS ..................................................................................................... 62 ORGANIC CHEMISTRY REVIEW – THROUGH ALCOHOLS........................................................................... 63 Br .......................................................................................................................................................... 63 6. Write Formulas (Expanded as above). .......................................................................................... 63 Cis-2-butene ___________________________________ .......................................................... 63 2-cyclopentyl-3,3-dichloro-1-hexene ___________________________________ .......................... 63 3,3-diamino-1-butyne __________________________________ .................................................. 63 Alcohol and Oxygen Compounds Reaction Mechanisms ......................................................................... 64 A (down the flowchart) ............................................................................................................................ 64 B (up the flowchart) .................................................................................................................................. 64 Reactions of alcohols ................................................................................................................................ 65 3 +H2O ......................................................................................... 64 Reactions of alcohols cont. ..................................................................................................................... 66 Page Other Alcohols PROPERTIES OF ALCOHOLS ....................................................................................................................... 67 Chemistry Preparation of Alcohols ........................................................................................................... 68 Predict Product or Missing Reactant ........................................................................................................ 69 A) ...................................................................................................................................................... 69 F) G) C–C–C CN ................................................................................................. 69 OH C–C–C I) C – C – C ............................................................................................................ 69 OH C – C – C ......................................................................................................... 69 Do in O ...................................................................................... 69 Show the steps necessary ......................................................................................................................... 70 Naming Organic Compounds Containing Oxygen..................................................................................... 71 Naming Aldehydes and Ketones ............................................................................................................... 72 PROPERTIES OF ALDEHYDES AND KETONES #1 ........................................................................................ 73 MULTISTEP SYNTHESIS Do the following conversions ...................................................................... 75 ALDEHYDES AND KETONES.............................................................................................................. 76 NAMING ACIDS ..................................................................................................................................... 77 Page 4 FORMULA WRITING: ACIDS ...................................................................................................................... 78 Organic Families and Functional Groups Family Functional Group - Functional Group R = carbon group X = halogen (F, Cl, Br, I) Example Alkanes Carbon, Hydrogen, and single covalent bonds only. Propane Alkenes = | | R–C=C–H Propene Alkynes R–CC–H Propyne Alkanols (Alcohols) -OH R – OH Propanol -O- R – O – R’ Methyl Ether || -C-H H | R–C=O Alkoxy Alkanes (Ethers) Alkanals (Aldehydes) Alkanones (Ketones) O || -C- Alkanoic Acids (Carboxylic Acids) O || -C-OH Esters O || -C-O- Propanal O R – C – R’ Propanone O R – C – OH O R – C – O – R’ Propanoic Acid Methyl Propanoate Amines | -N- R’ | R– N-R” Aminopropane Amides O || | -C-NH O R’ || | R -C-NH Propanamide -F fluoro-) Haloalkanes –Cl (chloro-) (Alkyl Halides) -Br (bromo-) -I (iodo-) R – X (X represents any halogen) Bromopropane H H H | | | H -C – C – C –H | | | H H H H H H | | | C=C–C–H | | H H H | H–C C–C–H | H H H H | | | H – C – C – C –OH | | | H H H H H | | H–C–O–C–H | | H H H H | | H–C–C–C=O | | | H H H H H | | H–C–C–C–H | || | H O H H H | | H–C–C–C=O | | | H H OH H H H | | | H–C–C–C–O–C–H | | || | H H O H H H H | | | H – C – C – C –NH2 | | | H H H H H | | H – C – C – C =O | | | H H NH2 Br H H | | | H - C – C – C- H | | | H H H Page 5 Aromatic NAME____________________________DATE_____________________________ CLASS____________________________TEACHER_________________________ ORGANIC FAMILIES 1 Tell which organic family each of the following compounds belongs to. Also, pick out the functional group(s) in each compound. Write the family on the first line and the functional group(s) on the second. You may have to draw an expanded structural formula for the compound first. O 7. ____________________________ ____________________________ O 2. CH3CH2CH2CH2CH2C ________________________ ________________________ 8. H ____________________________ ____________________________ 3. CH3CH2CH2CH(CH3)CH3 CH3CH2CH2CH2C 9. CH3CHClCH2CH3 10. CH2 CHCH2CH2CH3 ____________________________ ____________________________ CH3CH2CH2CH2CH(NH2)COOH ________________________ ________________________ 11. ____________________________ ____________________________ 6. CH3CH(NH2)CH2CH2CH3 ________________________ ________________________ OH ____________________________ ____________________________ 5. CH3CH2OCH2CH2CH2CH3 ________________________ ________________________ ____________________________ ____________________________ O 4. CH3CH2CCH2CH3 CH CCH2CH2CH3 ________________________ ________________________ 12. CH3CHOHCH2CH2CHOHCH3 ________________________ ________________________ 6 CH2OHCH2CH2CH3 Page 1. ORGANIC FAMILIES 2 Draw an expanded structural formula and a condensed structural formula for any compound that would belong to each of the families named below. (to be consistent use propane as the base chain) 1. Alkene 6. Aldehyde 2. Carboxylic acid 7. Alcohol 3. Ketone 8. Amino acid 10. Alkyne. 7 5. Alkane 9. Alkyl halide (haloalkane) Page 4. Ether Organic nomenclature part (1) Chemicals compounds that contain the element Carbon are known as organic compounds. “Organic” comes from the fact that until the mid 1800’s it was thought that these chemicals could only be derived from living plant or animal components. In 1828 Friedrich Woher converted the inorganic ammonium salt of cyanic acid into urea, which is an organic compound. Today hundreds of thousands of new organic compounds are discovered each year. With so many new carbon compounds being synthesized by research chemists each year, it became very important to have a systematic method of naming these compounds. Today most chemists use what is called the IUPAC system of nomenclature. (IUPAC standards for International Union of Pure and Applied Chemists). This system gives you the names of the simple organic compounds and then shows how to combine these names to represent the more complicated compounds. The simple organic compound are called “hydrocarbons” because they contain only carbon and hydrogen atoms. The simple groups of hydrocarbons are called the alkanes. Alkanes consist of straight chains of carbon atoms bonded together. For our purposes today we will consider derivatives of the first ten alkanes. These compounds are shown below. # Name Carbon Molecular Structural Formula Formula # Name Carbon Molecular Structural Formula Formula 1 Methane CH4 CH4 6 Hexane C6H14 CH3(CH2)4CH3 2 Ethane C2H6 CH3CH3 7 Heptane C7H16 CH3(CH2)5CH3 3 Propane C3H8 CH3CH2CH3 8 Octane C8H18 CH3(CH2)6CH3 4 Butane C4H10 CH3CH2CH2CH3 9 Nonane C9H20 CH3(CH2)7CH3 5 Pentane C5H12 CH3CH2CH2CH2CH3 10 Decane C10H22 CH3(CH2)8CH3 *Note: When writing the symbols for organic compounds, chemists usually omit the Hydrogen atoms from the structural formulas as shown above. Since some of the formulas can get quite complicated we simply show each Hydrogen as a line extending from the Carbon atoms. The lines between the Carbon atoms represent bonds that are holding the Carbon’s together. H H C C C C H H H H H can be written as Often, two or more of the alkanes shown above are joined together to form a compound consisting of multiple chains. When naming compounds such as this we will name the shortest branch first, however we will change the ending of the shortest branch to end in –yl, followed by the name of the longest branch. We must also use a numeral to denote the position of the short branch on the longest Carbon chain. Study the following examples: | | -C-C| | | | | | | | | | -C---C---C----C---C- 2-methylpentane -C---C----C---C---C3-methylpentane | | | | | | | | | | 8 Ex H Page H H ORGANIC NOMENCLATURE Part 2 In Part (I) you worked on naming simple organic compounds called alkanes. Some of these alkanes were found with “side Chains” attached to the main Carbon chain. We will consider naming alkanes that contain two or more side chains. The rules will be basically the same with only a few modifications. Below is the chart that you will need to help you with today’s assignment. # Carbon Name Molecular Expanded Formula Structure Condensed Structure 1 Methane CH4 -c- CH4 2 Ethane C2H6 -c-c- CH3CH3 3 Propane C3H8 -c-c-c- CH3CH2CH3 4 Butane C4H10 -c-c-c-c- CH3CH2CH2CH3 5 Pentane C5H12 6 Hexane C6H14 7 Heptane C7H16 8 Octane C8H18 -c-c-c-c-c-c-c-c- CH3(CH2)6CH3 9 Nonane C9H20 -c-c-c-c-c-c-c-c-c- CH3(CH2)7CH3 10 Decane C10H22 -c-c-c-c-c-c-c- -c-c-c-c-c-c-c-c-c-c- Numbers for amount of carbons 1 meth 2 eth 3 prop 4 but 5 pent 6 hex 7 hept 8 oct 9 non 10 dec CH3(CH2)4CH3 CH3(CH2)5CH3 CH3(CH2)8CH3 11 12 13 14 15 16 17 18 19 20 undec dodec tridec tetradec pentadec hexadec heptadec octadec nonadec icos 9 -c-c-c-c-c-c- CH3CH2CH2CH2CH3 Page Numbers for how many of one group there is: 1 mono 9 nona 2 di 10 deca 3 tri 11 undeca 4 tetra 12 dodeca 5 penta 6 hexa 7 hepta 8 oxa -c-c-c-c-c- Organic Nomenclature Part 3 In the previous two examples, the numerals 2 and 3 were used to show which carbon in the main chain had the methyl group attached to it. WHEN NUMBERING THE LONGEST CARBON CHAIN, ALWAYS BE SURE TO START NUMBERING THE CHAIN AT THE END CLOSEST TO THE SIDE CHAIN. STUDY THE FOLLOWING EXAMPLES: | || | || -C-C-C-C-C-C| | | | | | -C| 2-methylhexane BE CAREFUL WHEN FINDING THE LONGEST CARBON CHAIN FOR NUMBERING PURPOSES. THE LONGEST CHAIN ISN’T ALWAYS THE HORIZONTAL CHAIN! WRONG | | | || | -C-C-C-C-C-C| | | || | -C5-methylhexane | || | | | C-C-C-C-C | -C| -C| 4-ethylpentane WRONG RIGHT | | | | | C-C-C-C-C| -C| -C| 2-ethylpentane WRONG | | | | | C-C-C-C-C| -C| -C| 3-methylhexane RIGHT EXAMINE THE FOLLOWING EXAMPLES AND THEN TRY TO NAME EACH OF THE COMPOUNDS ON YOUR WORKSHEET. 1) highlight the main chain 2) circle the subgroups 3) number the chain | | | | | | | | | | | | | | | | C-C-C-C-C-C-C-C-C-C-C-C-C-C-C-C| | | C-C-C| | | -C-C-CRead | | and highlight the rules that are|new to you. | -C-C-C3 methylpentane | | | 5-methylundecane -C3 methylheptane | || | | | | | - C-C-C-C-C-C-C-C| | | | | || | octane | | | C-C-C| -C| methylpropane | -C| -C-C- 2-methyl pentane | -C| | | | | | | | C-C-C-C-C-C- C-C| | -C-C| | -C3 ethylheptane | | | | | | | C-C-C-C-C-C-C| -C| 2-methylheptane No numbers needed because 1-methyl or 3methyl would be butane C / C | C \ \ C | C / C Cyclohexane (add in H’s) | | | | | | | C-C-C-C-C-C-C| -C| -C-C-C| 5-methyldecane | 10 | | | | C-C-C-C| -C| 2-methylbutane Page || | | | C-C-C-C-C-C | -C| 2-methylhexane 3.4 Naming Alkanes Page 11 Directions: Read and HIGHLIGHT the structures to understand the naming/numbering system. Page 12 3.4 Naming Alkanes cont. Page 13 3.4 Naming Alkanes cont. Page 14 3.4 Naming Alkanes cont. Page 15 3.4 Naming Alkanes cont. Page 16 3.4 Naming Alkanes CLASSWORK. 3.4 Practice Problems Page 17 WRITE THE ANSWERS TO THESE PROBLEMS ON A SEPARATE PAGE. REMEMBER TO “COUNT, HIGHLIGHT, and NUMBER, CIRCLE” Worksheet 3 Organic Nomenclature You MUST 1) highlight the longest chain 2) circle the sub group 3) number the longest chain Name the following molecules: 1. | | | | | -C-C-C-C-C| | | | | -C| -C| 2. | | | -C-C-C| | | -C| 3. | | | | | | | -C-C-C-C-C-C-C| | | | | | | -C| -C| Give the structure for each compound named below. DRAW IN ALL HYDROGENS. (draw H’s) 6. 5-butylnonane 8. 1-ethylcycloheptane (draw H’s) 18 7. cyclopentane 5. 5-propyldecane Page 4. 3-methyloctane Identify all the functional groups Circle and identify all the functional groups. Use different colors for each type. Complete the assignment on the other side of this paper. Piperine (from black pepper) Cocaine (the coca bush) Caffeine (coffee and tea) Ca\\ Pyrethrin (a natural 19 Penicillin G (antibiotic) Page Cantharidin (blister beetle) insecticide) Nomenclature Examples In today’s work we will look at naming alkanes that have two or more side chains attached to the main carbon chain. The same rules apply that we used in Part (1) however we will need to designate all positions of the side chains with numerals. If two of the attached side chains are attached to the main chain, the side chains are named in alphabetical order. The side chains are still assigned numerical positions along the main chain starting with the end closest to the first branch regardless of the alphabetical nature of the names of the groups. Examine the compounds shown below. Directions: 1) highlight 2) circle 3) number in order to understand this page. ι ι ι ι ι ι ι ι Notice that we started assigning numerals at the left side C-C-C-C--C-C-C-C of the main 8 carbon chain. However, we named the ethyl ι ι ι ι ι ι ι ι group before the methyl group due to the alphabetical -C- -Corder of ethyl and methyl ι -Cι 5-ethyl-3methyloctane ι ι ι ι ι ι C-C-C-C--C-Cι ι ι ι ι ι -C- -Cι | 2,4-dimethylhexane -Cι ι ι ι ι ι ι C-C-C-C--C-C-Cι ι ι ι ι ι ι -C- Here we have two groups that are exactly the same attached to our main 6 carbon hexane chain. We must use the numerals to denote the position of both of the methyl groups. The name dimethyl hexane does not supply adequate information to identify this compound. In this case we started numbering our main carbon chain on the right hand side because this was the side closest to the first side branch. Again, the name dimethyl heptane would not adequately describe this compound 3,3-dimethylheptane -Cι ι ι ι ι ι ι ι C-C-C-C--C-C-C-C ι ι ι ι ι ι ι ι -C- -Cι - C| 5-ethyl-3,3-dimethyl-octane ι -Cι ι ι ι ι ι ι ι C-C-C-C--C-C-C-C ι ι ι ι ι ι ι ι -C- -C| ι 3,3,5-trimethyloctane Here we begin numbering the 8 carbon chain at the left which is closest to the first side chains. The dimethyl groups are NOT alphabetized under “d” but for “m” for methyl. Alphabetically, the dimethyl comes after the ethyl and is thus named second. Here we have three identical methyl groups and thus use the prefix “tri”. We begin numbering the side chains at the left which is the closest to the first methyl group. 20 3-ethyl-6methyloctane | Here octane is the longest carbon chain. By alphabetical order we decided to name ethyl before methyl. Page ι ι ι ι ι ι ι ι C-C-C-C--C-C-C-C ι ι ι ι ι ι ι ι -C-C| - C| Worksheet 4 Organic Nomenclature Part (II) STUDENT DIRECTIONS: Give the name for each compound shown in the first column and the structure of each compound named in the second column. Directions: (1)highlight the main chain, 2)circle the subs, 3)number the chain) 4) name it or draw as appropriate. Ι | 3,3 diethylpentane -C- -Cι ι ι ι ι ι ι - C- C- C- C- C- C- Cι ι ι ι ι ι ι ι ι ι ι ι ι ι ι ι ι - C-C-C-C--C-C-C-C –C-C ι ι ι ι ι ι ι ι ι ι - C-C| ι -Cι -Cι ι -Cι ι ι ι - C-C-C-C-ι ι ι ι -Cι ι ι ι ι ι -C-C-C-C-C-C – ι ι ι ι ι ι 2-methyl-5-propylnonane ι -Cι ι ι - C-C-C ι ι ι -Cι ι ι ι ι ι ι ι ι - C-C-C-C--C-C-C-C – ι ι ι ι ι ι ι ι -Cι ι -C-Cι ι -Cι ι ι ι ι ι ι - C-C-C-C--C-Cι ι ι ι ι ι -Cι ι ι ι ι -C-C-C-C-C | | | | | -C- 3-ethyl-3-methylhexane 3-ethyl-2-methylhexane 21 2,3,4-trimethylhexane Page | 3,3-diethyl-5,5-dipropyldecane Page 22 Naming Saturaded Hydrocarbons I Page 23 Naming Saturaded Hydrocarbons II Formula Writing: Saturated Hydrocarbons 4. 2,3,3-trimethylheptane 2. cyclobutane 5. cis-1,3-diethylcyclopentane 3. 2,2-dimethyl-3-propylhexane 6. 2,2,3,4-tetramethyloctane 7. 2,7-dimethylnonane 10. 3-methyl-4-propylheptane 8. 2,3,3-trimethylpentane 11. 3-ethyl-2-methylpentane 9. 2,4-dimethylhexane 12. 1,2-diethyl-4-methylcycloheptane Page 1. 2-methylhexane 24 Write expanded structural formulas for the first six compounds and condensed structural formulas for the last six compounds. Check to be sure that the given name is correct. Naming Organic Functional Groups Form WS11.3.2A Page 25 Expand the ones that are not expanded and name the functional groups. Page 26 3.1 Functional Groups Page 27 3.1 Functional Groups Practice Problems Page 28 Recognizing Functional Groups Page 29 Recognizing Functional Groups cont. ALKANE NAMING: iso, neo, & cyclo Examples: 5 isopropylnonane 1 - pentylcyclohexane or 1 - cyclohexylpentane Pentane (C5H12) 5 - neobutylnonane Chain neopentyl group 5 - isopropylnonane Chain isobutyl group NAME THE STRUCTURES 1.) 2.) name two ways 30 4.) Page 3.) Alkanes I . + CH4 ----->CH3I + H . (unstable) 3. CH4I ------>CH3I + H . 4. H . + I . ---->HI Page 2. 31 Preparation of: Alkanes are generally prepared from the refining of crude oil. Later, we will see that they can also be obtained from alkenes and alkynes. Reaction of: There are only two significant reactions of alkanes that we will consider: combustion and halogenation. Combustion: Combustion involves the use of alkanes as fuel. In general, the alkane is mixed with oxygen and burned producing carbon dioxide and water as the products. When this happens we refer to the process as complete combustion. If not enough oxygen is present then incomplete combustion occurs producing carbon monoxide and other complex products. We will always assume complete combustion occurs. Generally: flame Hydrocarbon + x Oxygen -------> y Carbon dioxide + z Water Examples: flame 2C2H6 + 7O2 -------> 4CO2 + 6H2O flame C11H24 + 17O2 -------> 11CO2 + 12H2O Halogenation: Halogenation involves the substitution of an alkane’s hydrogen by an atom of any one of the halogen atoms (F, Cl, etc). An alkane’s hydrogen is defined as a hydrogen bonded to a carbon atom which has only single bonds to other carbon atoms or other hydrogens. The process requires ultraviolet light to occur. The product is a haloalkane with one atom of halogen substituted into the alkane for each molecule of halogen used. From each molecule of halogen used we also obtain one molecule of the hydrogen halide (hydrohalogenic acid). This product is formed from the left over halogen atom and the hydrogen atom removed during the substitution. In this reaction the substitution can occur at any alkane hydrogen in the molecule so the student is free to choose which hydrogen atom(s) to substitute. Generally: Using X to represent any halogen Alkane + nX2 -------> alkane-Xn + nHX Examples: CH4 + Br2 -------> CH3Br + HBr CH4 + 4Br2 -------> CBr4 + 4HBr Mechanism of the Substitution Process (Halogenation): The sequence of steps involved in a chemical process is referred to as the mechanism. In general, halogenation occurs as a four step process: 1. The ultraviolet light photon collides with the halogen molecule and separates it into two very reactive atoms. 2. The halogen atom collides with an alkane carbon atom and bonds to it. 3. The carbon atom now has five bonds making it unstable. One bond breaks. If it is the carbon – halogen bond we return to the start and nothing has happened. If it is the carbon – hydrogen bond, a substitution of halogen for hydrogen has occurred. 4. The other halogen atom from step 1 combines with a removed hydrogen forming the hydrogen halide. Example: UV CH4 + I2 -----> CH3I + HI Sequence of Steps 1. I : I + photon UV ------> I + I Properties of Alkanes hexane + oxygen ------> 2. ultraviolet light 2 – methylbutane + chlorine ------------------------> 3. 2,3 – dimethylpentane + dilute sulfuric acid ------> 4. ultraviolet light methane + chlorine (4 steps) (4Cl2) -----------------------> 5. butane + sodium ------> 6. uv propane + bromine ------> 7. 3 – ethylpentane (oxidized) -------> 8. ultraviolet light ethane + fluorine ----------------------> Page 1. 32 Write an equation that shows what happens in each of the following reactions. Name all organic products formed. If no reaction occurs, write N.R. If more than one product is possible, make a note to that effect. “∆” means “as flame or heat is present”. PROPERTIES OF ALKANES REACTIONS Supply the missing reactant and/or product. 1. UV C4H10 + ____________ -------> _________________ + 2HI 2. ___________ + 8O2 -------> 5CO2 + _________________ 3. UV CH3CH2CH3 + ___________ ------> no reaction 4. UV _____________ + 3Cl2 ------> _______________ + _________________ 5.) 6.) ____________ + ______________ -------> 3CO2 + 4H2O UV _____________ + N2 ------> ___________________ Page 33 7.) ______________ + Cl2 ------> ____________________ Page 34 Organic Flowsheet Alcohols and Grignard Reactions Balanced Reactions using KMnO4 3C3H7OH + 2KMnO4 3CH3COCH3 + 2MnO2 + 2H2O + 2KOH 1o alcohol Cold aldehyde 3CH3CH (OH) CH3+ 2KMnO4 3CH3COCH3 + 2MnO2 + 2KOH + 2H2O 2o alcohol warm Ketone 3C2H5CHO + 1KMnO4 + 3OHAldehyde warm 3CH3CH2COOH + 1MnO2 + 1KOH + 1H2O Carboxylic Acid Grignard Reactions with Aldehydes and Ketones All reactions of Grignard reagents are like the carbon dioxide case: the R adds to the C of the carbonyl group and eventually - H to the O. So from an aldehyde or ketone we can make an alcohol - either primary, secondary or tertiary. The only difference between these three reactions is the number and nature of the group(s) attached to the C=O. Making a primary alcohol from an alkyl bromide and formaldehyde Making a secondary alcohol from an alkyl bromide and an aldehyde Making a tertiary alcohol from an alkyl bromide and a ketone Page 35 Synthetic applications of highly reactive organometallic reagents such as alkyllithium (LiR) and Grignard (RMgX). Sulfoxides (R2SO), for example, are prepared by treating thionyl chloride (SOCl2) with a Grignard reagent. Organic Synthesis Organic synthesis is the process of changing an organic substance into a different organic substance by organic chemical reactions. There are two major groups of organic syntheses that we will study: single step processes and multistep processes. Single Step Processes: A single step process involves the use of only one chemical reaction to change a substance belonging to a certain family into a new substance belonging to another family. You are already familiar with many single step processes. You know, for example, that you can treat an alkane with a halogen in the presence of ultra violet light and change it into a haloalkane. As another example, you can treat an alkene with water and convert it into an alcohol. In essence, what we do is change a certain functional group (ie, a double bond) into a different functional group (ie, C-OH). Multistep Synthesis: C C C C KOH Br2 UV C C Br In this process, the goal is the same as with single step synthesis: to change a functional group in a molecule into a different functional group. The difference with multistep synthesis is that it must be done by a series of several chemical reactions instead of only one reaction. The reason for using a series of steps is no single step is known for making the desired change. In the above example, the goal is to change ethane into ethene. The problem is no known reaction will cause the desired change. However, we do know how to change ethane into bromoethane and we also know how to change bromoethane into ethene. If we link the two reactions, we can reach our goal. In the laboratory we would react ethane with bromine in the presence of ultraviolet light, thus forming bromoethane. We would collect and purify the product bromoethane and then react it with potassium hydroxide forming the ethene and another product, potassium bromide. The process (ie. Starting point and goal) is written in a horizontal line and then the individual steps are presented in a loop below the overall process. To simplify the diagram, the non organic products (ie. Potassium bromide) are omitted. If they are included, it can be confusing whether they are products from the previous step or reactants fro the next step. The necessary reactants and conditions (ie. Br2, UV &KOH) are generally written above or below the arrow(s). Our primary interest is in showing what changes happen to the original molecule at each step in the process. Page 36 See the handout “Use of the Organic Flowsheet” for help doing Multistep synthesis problems. Organic Chemistry Multistep Synthesis MAPPING List the sequence of families involved in the following syntheses, include the reactants necessary to produce the product: (#1 is done for you) This will be called MAPPING 1. alkane Alkane X2/uv haloalkane alcohol (give two ways) KOH alcohol Or Alkane X2/uv haloalkane KOH 4. alkene 5. alkyne 6. alkane trihaloalkane ketone ketone cyanoalkane cyanoalkane 37 3. haloalkane alcohol Page 2. alkyne alkene H2O/H+catalyst Multistep Synthesis 1 H H C C H H H H C C H H H cyanoalkane H cyanoalkane Page H H 38 Map 2 ways to this destination. Show reactions and side products. Mapping Multistep Synthesis 2 1. alkane alkanone Alkane 2X2/uv dihaloalkane 2KOH alkyne 2H2O alkanone 2. alkane 3. alkyne alkanol alkanol In problems 4, 5, and 6, write out the multistep synthesis from above using the structures not the names ) Use Propane as the base molecule. Show all side products. 4. (#1) C-C-C 5. (#2) C-C-C 6. (#3) Page 39 C-C-C Nomenclature Exercise H H C H H H C H H C I C H H H C H C H H H C H H C H H C H H 1. Br H C H H C H H C C H H Cl C 2. 4. CH3CH(CH3)CH2CHBrCH(CH3)CH3 H H C H H H C H H C H C H C H H H H C C H H H H C H H C H H CH3 H3C CH H C H CH3 CH3 CH CH2 HC CH3 Br 3. 5. 6. (CH3)2CHC(C2H5)3 CH3 CH3 CH2 HC CH C CH2 CH3 H2C CH2 CH3 CH Cl CH2 HC CH3 40 H3C Page CH3 CH2 Haloalkanes The reaction which characterizes the haloalkane family is that process which eliminates the halogen atom(s) from the carbon atom of the chain. The reaction would be represented as follows: Haloalkane + KOH -----> alcohol + K-X ( X= halogen atom ) The reaction is most easily understood if you remember that there is generally a difference in electronegativity between the halogen and the carbon atom ( C-Cl difference is 0.5 ). The result is that the halogen atom will be slightly negative compared to the carbon atom. We can take advantage of this difference by adding something positive to the reaction container. A substance found to be very effective in this process is the potassium ion in potassium hydroxide (KOH) . The positive potassium ion attaches to the halogen and helps to pull it off the carbon chain. When the halogen atom separates from the chain, it will take the bonding electrons with it ( because of its higher electronegativity ). The remaining carbon chain now has a positive charge where the halogen atom used to be. C-C-C-C-C + K+ ------> C-C-C-C-C + KBr | Br This carbon chain ion must now react in such a way that the charge is neutralized. The particle is then back to the neutral state of a stable molecule. There are two ways in which this can happen. Which way actually occurs is governed by the conditions under which the process is conducted. We will simply assume that you can do whichever process you need to do. The first possibility for what can happen is that the positive carbon atom can collide with the negative hydroxide ion used to supply the potassium ion originally. If this happens, the result is an alcohol. A specific example would be: C-C-C-C-C + KOH ------> C-C-C-C-C + KBr | | Br OH The second possibility is a little more complicated: Page haloalkane + KOH -----> alkene + K-X + H-OH 41 A summary of the second process is: Haloalkanes cont. On a carbon chain, the hydrogen atoms are very slightly positive compared to the carbon atoms. The electrons in the carbon atoms next to the positive carbon atom which lost the halogen are drawn towards the positive carbon weakening the C-H bond. | | v v C-C—C--C-C | + | H H e---> <-- eThe hydroxide ion is then able to pull off the hydrogen atom of one of the carbon atoms marked with the arrows (carbons #2 & #4 ) in the above diagram. The bonding electrons are left behind on the more electronegative carbon atom. These electrons can now be used to form a pi bond between the two C atoms giving an alkene product and water. | | v v C—C--C--C--C ------> C-C=C-C-C | | + H H -OH + HOH A specific example would be: C-C-C-C-C + KOH ------> C=C-C-C-C + KBr + HOH | Br Add this general reaction to your flow sheet now before you forget. PRODUCTION OF ALKYNES WITH THIS PROCESS: If a haloalkane has two halogen atoms and two hydrogen atoms next door, it can undergo the above second possibility twice ( given two KOH ) to form an alkyne A summary of the this process is: dihaloalkane + 2 KOH -----> alkyne + 2K-X + 2H-OH A specific example would be: Page Br Br 42 C-C-C-C-C + 2KOH ------> C = C-C-C-C + 2KBr + 2HOH | | Reactions of haloalkanes Name Period Supply the missing components or if nothing will happen write N.R. (Double and triple bonds form towards the center of the molecule. (See first problem) KOH 1. C-C-C-C C-C=C-C + KBr + H2O | rather than Br C-C-C=C 2. KOH Cl 5. Br | C-C-C | Br KOH 2KOH C | C-C-C-C + 2KOH | I (iodine) 43 4. C Cl | | C-C-C-C | C Page 3. Chemistry Worksheet—Prepartions Instructions: Show how to prepare the indicated product using the given reactant. CH2I2 2. CH3CH2CH2OH 4. CH2CH3 | CH3CH2C=CH2 5. butane 6. Br | C-C-C 7. CH3CH3 CH3CH2CN H | CH3CH2CCH2CH3 | CH3 2-butanol Br | C-C-C CH3CH2MgBr 44 3. CH3CH3 CH3CH2CH2Br Page 1. CH4 Alkenes Additional Rules: 1.) Functional group is on the longest chain 2.) Number from end closest to functional group Naming Examples: C | C-C-C=C-C-C | C C-C=C-C-C 2 - pentene or pent -2- ene 2, 2 - dimethyl -3- hexene or 2, 2 - dimethyl hex -3- ene C-C | C-C-C-C-C-C=C | C-C 6 – ethyl-6 - methyl, -1- octene or oct -1- ene 1, 4 - cyclohexadiene or cyclohexa -1, -4 diene NAME THE EXAMPLES ON this SHEET. Note: It is permissible to leave the hydrogen atoms off of any structures. Just remember that there are enough hydrogen atoms in the molecule such that every carbon atom has four (4) bonds. 1.) 2.) 3.) 4 .) remember the functional group gets the lowest number 45 6.) Page 5.) Page 46 Naming Alkynes and Dienes FORMULA WRITING: ALKYNES AND DIENES Write expanded structural formulas for the first six compounds and condensed formulas for the last four compounds. If geometrical isomers are possible but not specified, write either form. Check to be sure that the given name is correct. 5. 2,3-diethyl-1,3-hexadiene 5,6-diethyl-1,3-cyclohexadiene 7. 2-methyl-1,3butadiene 3. 2,4-dimethyl-3-ethyl-2,4-hexadiene 8. Acetylene 4. 4,4,5-trimethyl-2-heptyne 9. 2-methylpent-1-ene-3 5,5-dimethyl-1,3-cyclopentadiene 10. 3,3,4,4,-tetramethyl-1,5-hexadiene 47 2. 6. Page 1. 3-methyl-1-pentyne CHEMISTRY REACTIONS OF ALKENE AND ALKYNES All the reactions of alkenes involve breaking the double bond into a single bond and adding a new atom to each of the original double-bonded carbons. Examples: Addition Reactions AB \ / | | C=C + AB --> -C-C/ \ | | They are termed AB additions. There is only one product in these reactions. The family to which this product belongs is determined by the nature of the A & B. Examples: 1. ADDITION OF H2 (A=H,B=H) HH \ / CATALYST | | C=C + H2 -------> -C-C- AN ALKANE * / \ | | 2. ADDITION OF HBr (HX WHERE X IS ANY HALOGEN) A=H,B=Br H Br \ / | | C=C + HBr ---> -C-C- AN ALKYL HALIDE * / \ | | 3. ADDITION OF X2 (X IS ANY HALOGEN) A=X, B=X Br Br \ / | | C=C + Br2 ----> -C-C- an alkyl halide * / \ | | Page 5. ADDITION OF HYDROGEN CYANIDE (HCN) H=A, CN=B H CN \ / | | C=C + HCN ----> -C-C- (a cyanoalkane) * / \ | | 48 4. ADDITION OF H2O (HOH) A=H B=OH H OH \ / | | C=C + H2O ---->-C-C- an alcohol * / \ | | Markownikoff's Rule: With the addition of an AB in which A is an H atom (H-B), the H goes to the carbon of the double bond which already has the most H atoms. Examples: H CH3 H CH3 | | HBr | | H--C=C--CH3 ----> H--C--C--CH3 | | H Br Reactions of alkynes are identical to those of alkenes except they can add 2 AB molecules. Examples: 1. Addition of H2 -C=C- + H2 H H H H catalyst \ / + H2 | | ----------> C=C ----------> -C-C/ \ catalyst | | alkene H H alkane 2. Addition of H2O and HBr -C=C- + H2O OH \ / + HBr ---------> C=C- ----------> / \ OH | | -C-C| | Br 3. Addition of 2Br2 -C=C- + Br2 Br Br Br Br | | + Br2 | | ---------> -C = C- --------> C-C | | Br Br Page 49 4. Any two A-B molecules can be added in any combination. Markownikoff's rule cont 5. If two water molecules are added, the result is unusual. Markownikoff's rule means that both OH groups will go to the same carbon.( see next page ) H OH OH O H2O | | H2O | | | || -C=C- -----> -C=C- ------> --C-C-- ----> -C-C +H2O | | | | | | OH (ADD TO FLOW CHART) (Automatically happens) This gives us a new reaction of alkynes: REACTION OF ALKYNES TO PRODUCE KETONES + ALDEHYDES H OH O H+ | | || H-C=C-H + 2 H2O ----> H-C-C-H- ---> -C--C--H +H2O CATALYST | | H OH Two oxygens singly bonded to the same carbon makes the carbon too positive so it's unstable. The molecule rearranges by ejecting one OH group and the H from the other OH group leaving a double bonded O on the original molecule. O H+ || C-C=C-C + 2 H2O ---> C-C-C-C + H2O ( overall process ) step 1 H2O H+ step 3 step 2 Page 50 H OH OH | | H2O | C-C=C-C ----> C-C-C-C H+ | OH PROPERTIES OF ALKENES I Write an equation that shows what happens in each of the following reactions. Name all organic products formed. Use structural formulas (C-C-C or ) 1. propene + bromine 2. 3-hexene + hydrogen chloride 12 O2 3. 1-octene (oxidized) 4. 2-methylpropene + hydrogen cyanide 5. cyclopentene + chlorine 15 O2 6. 2,3,3-trimethyl-1-heptene + oxygen 7. 2,3-dimethyl-2-butene + hydrogen Page 51 8. 1,2-dichloro-1-butene + chorine PROPERTIES OF ALKENES II Write an equation that shows what happens in each of the following reactions. Name all organic products formed. 1. 2,4-dimethyl-2-pentyne + ethyl alcohol 2. 1,1,2,3,3,3-hexachloro-1-propene + hydrogen chloride 3. ethylene + ethylene (3 steps) (NR) pressure 4. cyclohexene + hydrogen iodide 5. 2-methyl-3-chloro-4-ethyl-3-heptene + fluorine 6. 3,5-dichloro-4-methylcyclopentene + hydrogen bromide 7. 2-methylpropene (polymerized) (NR) Page 52 pressure Name: Date: Period: PROPERTIES OF ALKENES AND DIENES Write an equation that shows what happens in each of the following reactions. Name all organic products formed. 1. 1,4-cyclohexadiene + hydrogen bromide (one mole) H+ 2. 2-butyne + water (2 steps) 3. 1,3,5-decatriene (completely oxidized) 4. propyne + bromine (to completion) 5. 5-methyl-1,3-cyclopentadiene + hydrogen cyanide (one mole) 6. 1,3-butadiene (polymerized; 2 steps) 7. 3-hexyne + chlorine (xs) OH - 8. 3-methyl-1-butyne + ethanol C-------------C | | C------------C Page 10. O || C-------C | | C------ C 53 CN | 9. Hexane C---C---C---C---C---C | CN Alkane—haloalkane—alkyne—dicyanoalkane Organic Chemistry alkanes, alkenes, alkynes Complete the following reactions by supplying the missing reactants or products. 1. 2. | | | | | | -C-C-C-C-C=C| | | | + C | C-C=C-C-C | C H2 H2SO4 catalyst + KOH 3. | | | C=C-C-C-C| | | 4. \ / C | | || -C-C-C + KBr | | | + H2O HCN Br2 5. C-C-C-C-C C-C=C-C-C UV Multistep Synthesis 7. OH | C-C-C-C CH3CN Br Br | | C-C-C-C 54 CH4 Page 6. Chemistry Organic Reaction Give the steps required to do the following conversions. O || 1 . OH 2. Br I 3. Do the flowing Multistep Synthesis Use the format presented in class 3. C - C - C C-C-C O || C-C-C 55 2. Cl | C-C-C Page 1. C - C - C OH | C-C-C Organic Chemistry Show the Predicted Products Show the predicted Products (structural formula) 1. + 2. Cl2 UV + HCN (1 mole only) 3. + 2H2O Show the sequence of step necessary to make the following process happen. 4. C C-C-C-CBr | C-C-C-C-C C-C-OH 56 C Page 5. C Organic Reactions Worksheet Name Period Predict Products (add necessary chemicals) 1. Br | C-C-C-C-C-C 2. HCl Br2 3. C-C-C-C-C | | C C ||| C | 4. 2H2O Br Cl2 UV 5. 6. CN | C-C-C C8H14 I2 UV ? no UV Page 57 7. An unknown chemical is found later to have the formula C5H10. It reacts with I2 only in the presence of UV. What could its structural formula be? Predict Reactants: Complete the following processes 8. + 3HCl CN | | Br 9. 10. | Br C Br | | C--C—C | | C Br O || C---C 11. / C \ \ C=O / C--C 14. OH OH | | C—C---C---C---C C OH | | C—C---C---C---C | C 58 13. C-C-C Page 12. Chemistry Multistep Synthesis Show the steps required to go from the reactant to the product. | | | | -C-C-C-C| | | | | | -C-C| | 3. | -C| -C= C-C--C| | -C| 4. Br | | | -C—C—C| | | | | | | -C—C--C—C-OH | | | | | O -C| || | | -C---C—C—C| | | -C| Br | | | -C—C—C| | | 59 2. \ / | | C=C--C--C/ | | Page 1. ALCOHOLS These contain the -OH group. The general name is alkanol. CH3CH2OH is ethanol, also called ethyl alcohol. (1-ethanol unnecessary since no confusion of structure is possible. A.) CH3CH2CH2CH2OH __________________________________ B.) CH3CH2CHCH3 | OH ______2 – butanol or butan – 2 – ol______ C.) CH3 CH3 \ / CH | OH __________________________________ D.) H H H H H H | | | | | | H – C – C – C – C – C – C – CH3 | | | | | | H H H-C–H H H H | H-C-CH3 | OH __________________________________ (name by finding the longest chain containing the -OH group) E.) Br HO | | | – C – C – C – CH3 | | | COH 4 – bromo – 2 – methyl – 1,3 – butandiol OH | | –C–C– | | HO __________________________________ __________________________________ (commonly called ethylene glycol antifreeze) 60 G.) OH OH OH OH | | | | –C–C–C–C– | | | | Page F.) NAMING ALCOHOLS On the lines provided, write the correct name for each of the following compounds. Where appropriate, indicate whether an alcohol is primary, secondary, or tertiary. 1. CH3CH2CH2CH2OH ______________________________ 2. CH3CHOHCH2C(CH3)2CH3 ______________________________ 3. CH2OHCHOHCH2OH ______________________________ 4. (CH3)3COH ______________________________ 5. CH3CHClCHOHCH(CH3)C(CH3)3 ______________________________ 6. CH2ClCH2CH(CH3)C(OH)(C2H5)CH2CH3 Page 61 ________________________________ 6. 2,3-butandiol 2. 3-chloro-4-methyl-1,2-hexdiol 7. 2-pentanol 3. 1-hydroxyhept-2-yne (hept-2-yne-1-ol) 8. 2,4-dichloro-2-hexanol 4. 2,2-diethylcyclopent-1,4-diol 9. 2-methylhex-3-ene-1-ol 5. 3,4 -dimethyl-2 –ethyl-2- hexanol 10. 3-methyl-2,4-pentanediol Page 1. sec-butyl alcohol 62 FORMULA WRITING: ALCOHOLS Write a structural formula for each of the following compounds. Check to be sure that the given name is correct. ORGANIC CHEMISTRY REVIEW – THROUGH ALCOHOLS OH ___________________________________ ___________________________________ C–C–C | C–C–C–C–C–C–C–C–C | C | C–C–C CC–C–C–CC ___________________________________ ___________________________________ Br | C – C – C – C – C – Br | | Br Br ___________________________________ ___________________________________ 2-cyclopentyl-3,3-dichloro-1-hexene ___________________________________ 3,3-diamino-1-butyne __________________________________ Page Cis-2-butene 63 6. Write Formulas (Expanded as above). Alcohol and Oxygen Compounds Reaction Mechanisms KmnO4 KmnO4 1 alcohol aldehyde —— alkanoic acid LiAlH4 LiAlH4 A (down the flowchart) remove H2 B (up the flowchart) add H2 add H2O and remove H2 remove H2O and add H2 KmnO4 removes H LiAlH4 adds H A) Down OH- - - O O Mn RCH- - -O O H Li+1 H O- - - - H OH O- - H H Al H -H2O COH R COH R C- - H H H OH H RCH H +H2O 2o OH O RCH RCR can’t continue so ends as a ketone (secondary alcohol) R 3o OH O RCR RCR can’t start –no reaction (tertiary alcohol) R R 64 Other Alcohols H Page B) Up O OH- - - O O H2O RC RCOH Mn O H H- - - ---------- - - -O O Cold blocks RCOH Reactions of alcohols A. Oxidation Alcohols can be oxidized to aldehydes, ketones, and carboxylic acids by KMnO 4(or the ion Cr2O7-2). The conditions under which the reaction is done determine the results. If everything is kept cold, an aldehyde is produced from the corresponding primary alcohol and a ketone from the secondary alcohol. If the reactants are heated, the primary alcohol (or the aldehyde) is oxidized to the corresponding carboxylic acid. Since an oxygen is double-bonded to its functional group carbon in the products of this reaction, tertiary alcohols are not oxidized by this process ( because they have three C-C bonds to the functional group carbon ). KMnO4 is not reactive enough to break C-C bonds. Summary: cold primary alcohol --------------> aldehyde KMnO4 secondary alcohol --warm------------> ketone KMnO4 cold or hot tertiary alcohol --------------> no reaction KMnO4 warm primary alcohol --------------> carboxylic acid KMnO4 warm aldehyde --------------> carboxylic acid KMnO4 warm/cold ketone -------> no reaction KMnO4 Try these reactions (Cr2O7-2 can be used instead of KMnO4.) : warm 1. C-C-C-C-C -------> | KMnO4 OH cold 2. C-C-C-OH --------> KMnO4 Page hot --------> KMnO4 C OH | | cold 4. C-C-C-C-C -------> | KMnO4 C 65 O || 3. C-C-C Reactions of alcohols 5. cont. OH / C-C / \ warm C C -------> \ / KMnO4 C-C B. Dehydration This reaction is essentially the reverse of the water addition to alkenes we studied earlier. Concentrated sulfuric acid is used as the dehydrating agent. H OH | | C---C H2SO4 C=C +H2O C. Substitution 1. All alcohols can have the OH group replaced by a halogen using the chemical - phosphorous tri-halide (PBr3, PCl3 etc): PBr3 C-OH ------> C-Br + PBr2OH 2. This reaction is the reverse of the preparation of alcohols from haloalkanes. Hydrohalogenic acid or phosphorous trihalide is needed R-OH + H-X R-X + H-OH R-OH + PX3 R-X + PX2-OH Complete: PCl3 6. C-C-C-C ------> | C-OH OH | PBr3 C--C—C--C --------> | | C- C OH / C-C / \ PBr3 C C -------> \ / C-C Page 8. 66 7. PROPERTIES OF ALCOHOLS Write an equation that shows what happens in each of the following reactions. Name all organic compounds that are produced. Write NR if no reaction happens. (NOTE: Cr2O7= KMnO4-) Cr2O7= 1. 1-butanol (cold, dilute) 2. 2-methyl-1-pentanol + sodium 3. m-chlorophenol + chlorine 4. 2,2-dimethyl-3-hexanol + hydrogen bromide 2nd degree alcohol 5. ethylalcohol + hydrogenbromide 6. K MnO4 2-hexanol (cold, dilute) 7. 3-methyl-1-pentanol + acetic acid H2SO4 (concentrated) + Page 67 8. p-nitrophenol + propanoic acid Chemistry Preparation of Alcohols Worksheet O 1.) CH3CH2CH2C H ---------> C 2.) C C C C + __________ -----------> (remember the Russian) + __________ ------------> C 3.) C C C C C O 4.) C 5.) C OH C H2 + 2H2O ------------> ________________ ------------> C Br C C C C C + KOH ------------> (dilute) C C 6.) O 7.) C C C + + O2 H2 -------------> Flame -----------> C C C OH C C C LiAlH4 -------------> Page 8.) C 68 O Predict Product or Missing Reactant UV A) + 3Br2 Light B) Combustion + C) CC 7CO2 + 7H2O + H2O C C + Br2 HBr D) C E. C - C - C - C=C C Br | | C - C | C Multistep Syntheses KOH O || C–C–C F) C – C – C G) OH | C–C–C–C CN | C–C–C–C H) OH | C–C–C Do in 4 steps O || C–C–C 69 I) C–C–C | | C–C | CN Page C–C–C | | C–C Show the steps necessary to complete the following multistep syntheses. Map and show reactants 3.) C – C C–CC–C O || C – C – OH 70 OH | 2.) C – C – C – C C – C – OH Page 1.) C – C Naming Organic Compounds Containing Oxygen Naming the alcohols, aldehydes, ketones and carboxylic acids is easily accomplished by simply changing the ending of the name. To change the ending, simply take the corresponding alkane name and drop the “e” from the end. Then add the appropriate ending for one of the four families above. See the chart below: Family alcohol aldehyde ketone Carboxylic acid Formal Name alkanol alkanal alkanone alkanoic acid Ending ol al one oic acid Example 1-propanol propanal 2-propanone propanoic acid Note that since the aldehyde and carboxylic acid functional groups must be on the end of the longest chain their locations are automatically at carbon number one and need not be specified. For complicated molecules the ketone double bonded oxygen can be named as a substituent rather than as a family functional group. In this case it is called “oxo”. The alcohol group can be name as a “hydroxyl” substituent. Examples and sample problems: C-C-C-C-C-C-C-C-C=O 4-oxononanoic acid || | O OH C-C-C-C-C-C=O hexanal C-C-C-C-C-C-C-C=O || || O O 3,6-dioxooctanal C-C-C-C-C-C-C=O | | OH OH ___________________________________________ ___________________________________________ 71 C-C-C-C-C-C-C-C-C || | O Cl ___________________________________________ Page Try these: C-C-C-C-C-C-C-C =O | | C C-C Answers: 4-ethyl-6-methyloctanal, 5-chloro-3-nonanone, 5-hydroxyheptanoic acid Naming Aldehydes and Ketones 1. CH3CH2CH2CHO ____________________________ 9. =O 2. CH3CH(CH3)CH(CH3)C=O CH3 ____________________________ 3. CH2Cl(CHCl)3CHO ____________________________ 4. ___________________________ 10. CH3CHOHCH2CHClCH2CHO _______________________________ H3C =O CH3 ____________________________ 5. (CH3)3CC = O H ____________________________ 6. O || CH3CH2CCH2CH3 ____________________________ 7. (CH3)3 C C =O C(CH3)3 ____________________________ Page ____________________________ 72 8. CH2NH2C(CH3)2CH2C = O | H PROPERTIES OF ALDEHYDES AND KETONES #1 Write an equation that shows what happens in each of the following reactions. Name all organic products formed. 1. CH3C(CH3)2(CH2)4CHO + HCN -----------> (“AB” addition) 2. CH3CH(CH3)CH2CHO (mild oxidation) -----acidic-------> 3. CH3CHCl CCH(CH3)2 + H2 ------------> (CH3)3CC(Cl)2CHO + HBr ------------> 5. CH3CH(CH3)COCH2CH2CH3 (mild oxidation) ------------> 6. CH3CHICHICH(CH3)CH2CHO + HOH------------>(refer to alkyne H2O addition) Page 4. 73 O CHEMISTRY WORKSHEET: Aldehyde + Ketones #2 1. Cu CH3CH2CH2OH ------------> 250OC OH 2. KMnO4 CH3CH2CHCH3 ------------> (________) O 3. H2 CH3C H ------------> + Catalyst O 4. H2O CH3CCH3 + CH3MgBr -----------> OH C KMnO4 CH2CH3 -----------> 74 CH3 Page 5. CH3 Date: Period: MULTISTEP SYNTHESIS Do the following conversions 1. Acid name: _____________________ O || C – C – OH C–C 2. Ketone name: ___________________ O || C–C–C CC–C 3. Aldehyde name: _________________ O CN || | C–C–C C–C–C Page Reactant name: __________________ O O Br Br Br || || | | | C – C – C – C – OH C–C–C–C | Br 75 4. ALDEHYDES AND KETONES 1.) Synthesize pentanoic acid (5 carbons) from 2-bromopentane. Br OH H3C CH3 2-bromopentane H3C O Page 76 2.) You made two solutions of organic compounds. One is pentanal, the other is 3-hexanone. You forgot to label them, so you don’t know which is which. Since they smell very similar you can’t tell them apart by odor. How can you tell them apart? NAMING ACIDS On the lines provided, write the correct name for each of the following acids. 1.) CH3CH(CH3)CH2CH2COOH ______________________________ 2.) CH3CH(CH3)C(CH3)(C2H5)CH2COOH ______________________________ 3.) HOOCCH2CH2CH2COOH ______________________________ 4.) CH3CH2CH2CH(NH2)COOH ______________________________ 5.) CH(CH3)2C(CH3)2CH2COOH ______________________________ 6.) C(Cl)3C = O | OH ______________________________ 7.) HOOCCH2C(CH3)2CH2COOH ______________________________ 8.) CH3CH2CH2CHOHCH2COOH ______________________________ 9.) CH3CH=CHCH=CHCH2COOH Page 77 ______________________________ FORMULA WRITING: ACIDS Write structural formulas for the following acids. Check to be sure that each given name is correct. 3,3,4,6-tetramethyloctanoic acid 2. 2-aminobutanoic acid 7. 2-chloro-3-ethyl-4-methylhexanoic acid 3. 3-methyl-5-phenylpentanoic acid 8. trichloroacetic acid (2 carbons) /trichloroethanoic acid 4. 3,3-dimethylpentanedioic acid 9. 4-chloro-2,3,3-trimethyl-butanoic acid 5. 3-hydroxyhexanoic acid 10. heptanedioic acid 78 6. Page 1. formic acid (1 carbon) HCOOH