Organic Chemistry The study of carbon-containing compounds and their properties. The vast majority of organic compounds contain chains of rings of carbon atoms. Hydrocarbons . . . compounds composed of carbon and hydrogen. Saturated: carbon-carbon bonds are all single alkanes [CnH2n+2] H H H C C H H H Hydrocarbons (continued) Unsaturated: contains carbon-carbon multiple bonds. H H H C H C H C H Rules for Naming Alkanes 1. For alkanes beyond butane, add -ane to the Greek root for the number of carbons. C-C-C-C-C-C = hexane 2. Alkyl substituents: drop the -ane and add -yl. -C2H5 is ethyl Rules for Naming Alkanes 3. Positions of substituent groups are specified by numbering the longest chain sequentially. C C-C-C-C-C-C 3-methylhexane 4. Location and name are followed by root alkane name. Substituents in alphabetical order and use di-, tri-, etc. Substitution Reactions Primarily where halogen atoms replace hydrogen atoms. CHCl3 Cl2 h CCl 4 HCl Cyclic Alkanes Carbon atoms can form rings containing only carbon-carbon single bonds. C3H6, C4H8, C6H12 Alkenes and Alkynes Alkenes: hydrocarbons that contain a carboncarbon double bond. [CnH2n] CC=C propene Alkynes: hydrocarbons containing a carboncarbon triple bond. CCCCC 2-pentyne Nomenclature for Alkenes 1. Root hydrocarbon name ends in -ene C2H4 is ethene 2. With more than 3 carbons, double bond is indicated by the lowest numbered carbon atom in the bond. C=CCC is 1-butene Addition Reactions . . . in which (weaker) bonds are broken and new (stronger) bonds are formed to atoms being added. catalyst CH2 CHCH3 H2 CH3CH2CH3 Aromatic Hydrocarbons A special class of cyclic unsaturated hydrocarbons. Cl FeCl3 + Cl2 benzene + HCl Chlorobenzene Refinery Processes Cracking: large molecules broken down to smaller ones by breaking carbon-carbon bonds. Pyrolysis (thermal cracking): The process that produces cracking at high temperatures. Catalytic Cracking: Cracking at lower temperatures. Catalytic reforming: Alkanes and cycloalkanes converted to aromatic compounds. The Common Functional Groups Class Halohydrocarbons Alcohols Ethers Aldehydes General Formula RX ROH ROR O R CH The Common Functional Groups Class Ketones Carboxylic Acids Esters Amines General Formula O R C R' O R C OH O R C O R' RNH2 Polymers . . . are large, usually chainlike molecules that are built from small molecules called monomers. Monomer Polymer Ethylene Polyethylene Vinyl chloride Polyvinyl chloride Tetrafluoroethylene Teflon Types of Polymerization Addition Polymerization: monomers “add together” to form the polymer, with no other products. (Teflon) Condensation Polymerization: A small molecule, such as water, is formed for each extension of the polymer chain. (Nylon)