Organic Chemistry
Alkanes (end with –ane, simplest hydrocarbons, contain
only single covalent bonds)
# of C
Prefix
Simple Formula
1
methCH4
2
ethC2H6
3
propC3H8
4
butC4H10
5
pentC5H12
6
hexC6H14
7
heptC7H16
8
octC8H18
9
nonC9H20
10
decC10H22
-all alkanes that are straight chains are named
n-alkane (means normal)
C4H10 = n-butane
-look at pg 1010 *iso-, and neo-
Branched Chain Alkanes
-alkane group takes the place of a H atom
-called a substituent
alkyl group- hydrocarbon substituent
-ends with –yl (take away -ane)
-contains one less H
-look at # of C to name
ex- CH3 = methyl
C2H5 = ethyl
Naming Branched Chain Alkanes
1) Find the longest chain = parent molecule
ex- heptane
2) # the C’s in the chain, making sure alkyl
groups have lower numbers, can count
backwards
ex- 2,3,4 instead of 4,5,6
3) Add #’s to names of alkyl groups, with a dash
in between
ex: 2-methyl
3-methyl 4-ethyl
4) Use prefixes to denote multiples of the same
alkyl groups, commas between #’s
ex- 2,3-dimethyl
5) Put alkyl groups in alphabetical order
ignoring prefixes
ex- 4-ethyl-2,3-dimethyl
6) **Use proper punctuation
-commas separate #’s
-hyphens separate #’s and letters
-no spaces
7) Add parent chain name
ex- 4-ethyl-2,3-dimethylheptane
*Remember prefixes*
2 = di3 = tri4 = tetra5 = penta6 = hexa7 = hepta8 = octa9 = nona10 = deca-
Drawing Structural Formula From Name
1) Find parent chain and draw
2) # C’s on parent chain
3) Identify substituents and attach to proper C
4) Add hydrogen as needed
Try These!!
1) 3-ethylhexane
2) 2,2,4-trimethylpentane
3) 3-ethyl-3,4-dimethyloctane
saturated compounds- contain max # of H
-all alkanes, all single C-C bonds
unsaturated compounds- do not contain max #
of H
-contain double or triple C-C bonds
-alkenes and alkynes
Alkenes
-contain at least one double C═C bond
Naming Alkenes
1) Find longest chain containing double bond
-this is parent chain
-gets –ene ending
ex- butene
2) # so that C atoms of the double bond get the
lowest #’s, then look at alkyl groups to get
lowest #
-double bond gets numbered in the name
ex- 2-butene
3) Substituents get named the same as alkanes
ex- 2-methyl
4) Put all together
ex: 2-methyl-2-butene
Alkynes
-named same way except end in –yne
http://www.chembio.uoguelph.ca/educmat/chm1
9104/organic_nomenclature_quizzes.htm
Structural Isomers
-compounds that have the same simple formula,
but different structural formulas
Ex- C4H10
n-butane
2-methylpropane
Try This!!
Write the structural formulas/skeleton formulas
and names for the nine isomers of heptane
Cyclic Hydrocarbons-contain a hydrocarbon ring
-all single bonded cyclic hydrocarbons are
named with the prefix cycloexcyclopropane
-if have subgroups, name just like before
Try these!!
1-ethyl-3-methylcyclohexane
1,3-dimethylcyclopentane
unsaturated cyclic hydrocarbons/aromatic
hydrocarbons
-contain 6 carbon with 3 double bonds
-called benzene
=
-benzene can have subgroups coming off of it
1-ethyl-2,3-dimethylbenzene
methylbenzene
-if benzene is a substituent it is called phenyl
2-phenylpropane
-or isopropylbenzene
Functional Groups
**R represents C chain attached to functional
group
Halocarbons
R-X
X= a halogen
functional group = halogen
-use root of halogen to name
exchloromethane
1,4-dibromobenzene
Alcohols
R-OH
functional group = OH (hydroxyl)
-name same as others except ending on parent
chain drops the –e and gets an –ol
-must number where the -OH is located
-alcohols containing 2, 3 or 4 –OH get prefix
(diol, triol, tetrol) after parent chain
exmethanol
1,2-ethanediol
2-methyl-2-propanol
Ethers
R-O-R
functional group = ether
-name R groups then add ether (space between)
exethylmethyl ether
diphenyl ether
Aldehydes
functional group = carbonyl group
-name same as others, but gets the –al ending
* ═O is always on the terminal carbon, so no
need to number
expropanal
3-phenyl-2-propenal
2-methylbutanal
Ketones
functional group = carbonyl group
-to name, drop –e on parent chain and add –one
-number so ═O gets lowest #
expropanone
2,4-dimethyl-3-hexanone
diphenylmethanone
Carboxylic Acids
functional group = carboxyl
-ends with –oic acid
exethanoic acid
4-methyl-3-pentenoic acid
Esters
functional group = ester
-get –oate ending, with space between, parent
chain is where ester group is located
-esters have fruity, pleasant odors
exethyl ethanoate
butyl propanoate
ethyl pentanoate
Amines
functional group = amine group
-named by groups attached and end with amine
exethylamine
trimethylamine
ethylmethylamine
Summary
Type
halocarbon
alcohol
ether
aldehyde
ketone
Structure
R-X
R-OH
R-O-R
*on terminal carbon
carbonyl
carboxylic acid -COOH
ester
amine
Group
X=halogen
hydroxyl
ether
carbonyl
NR3
carboxyl
Ending
root of halogen
-ol
ether
-al
-one
-oic acid
ester
-oate
amine
amine