Organic Chemistry

78 CHAPTER 2 An Introduction to Organic Compounds

one word (unlike the common names of alcohols, ethers, and alkyl halides, in which

“alcohol,”“ether,”and “halide”are separate words).

The IUPAC system uses a suffix to denote the amine functional group. The “e”at

the end of the name of the parent hydrocarbon is replaced by “amine”—similar to the

way in which alcohols are named. A number identifies the carbon to which the nitro-

gen is attached. The number can appear before the name of the parent hydrocarbon or

before “amine.”The name of any alkyl group bonded to nitrogen is preceded by an

“N”(in italics) to indicate that the group is bonded to a nitrogen rather than to a

carbon.

The substituents—regardless of whether they are attached to the nitrogen or to the

parent hydrocarbon—are listed in alphabetical order, and then a number or an “N”is

assigned to each one. The chain is numbered in the direction that gives the functional

group suffix the lowest possible number.

Nitrogen compounds with four alkyl groups bonded to the nitrogen—thereby giv-

ing the nitrogen a positive formal charge—are called quaternary ammonium salts.

Their names consist of the names of the alkyl groups in alphabetical order, followed

by “ammonium”(all in one word), and then the name of the counterion as a separate

word.

Table 2.3 summarizes the ways in which alkyl halides, ethers, alcohols, and amines

are named.

CH 3

N+CH 3 HO−

CH 3

CH 3 N+

CH 3

CH 3 Cl−

CH 2 CH 3

CH 3 CH 2 CH 2

tetramethylammonium hydroxide ethyldimethylpropylammonium chloride

3-chloro-N-methyl-1-butanamine

2-ethyl-N-propylcyclohexanamine

CH 3 CHCH 2 CH 2 NHCH 3

4321

N-ethyl-5-methyl-3-hexanamine

CH 3 CH 2 CHCH 2 CHCH 3

12 3456

NHCH 2 CH 3

NHCH 2 CH 2 CH 3

Cl

CH 3

CH 2 CH 3

4-bromo-N,N-dimethyl-2-pentanamine

CH 3 CHCH 2 CHCH 3

54 3 21

CH 3 NCH 3

Br

CH 3 CH 2 CH 2 CH 2 NH 2 CH 3 CH 2 CHCH 2 CH 2 CH 3

1-butanamine

or

butan-1-amine N-ethyl-3-hexanamine

or

N-ethylhexan-3-amine

NHCH 2 CH 3

N-ethyl-N-methyl-1-propanamine

or

N-ethyl-N-methylpropan-1-amine

CH 3 CH 2 CH 2 NCH 2 CH 3

CH 3

4321 123456 321

CH 3 NH 2

CH 3 NCH 3

CH 3

methylamine

CH 3 NHCH 2 CH 2 CH 3

methylpropylamine

trimethylamine

CH 3 NCH 2 CH 2 CH 2 CH 3

CH 3

butyldimethylamine

CH 3 CH 2 NCH 2 CH 2 CH 3

CH 3

ethylmethylpropylamine

CH 3 CH 2 NHCH 2 CH 3

diethylamine

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