The Foundations of Chemistry

of alcohols are much higher than those of the corresponding alkanes (see Table 27-2)
because of the hydrogen bonding of the hydroxyl groups.
Most phenols are solids at 25°C. Phenols are only slightly soluble in water unless they
contain other functional groups that interact with water.

Uses

Many alcohols and phenols have considerable commercial importance. Methanol,
CH 3 OH, was formerly produced by the destructive distillation of wood and is sometimes
called wood alcohol. It is now produced in large quantities from carbon monoxide and
hydrogen. It is very toxic and causes permanent blindness when taken internally.
Ethanol, CH 3 CH 2 OH, also known as ethyl alcohol or grain alcohol, can be prepared
by fermentation of sugar. The most ancient written literature refers to beverages that were
obviously alcoholic!
Many simple alcohols are important raw materials in the industrial synthesis of poly-
mers, fibers, explosives, plastics, and pharmaceutical products. Phenols are widely used in
the preparation of plastics and dyes. Solutions of phenols are used as antiseptics and disin-
fectants. Some uses of polyhydric alcohols depend on their relatively high boiling points.
For instance, glycerine is used as a wetting agent in cosmetic preparations. Ethylene glycol
(bp 197°C), which is miscible with water, is used in commercial permanent antifreeze.

ETHERS

When the word “ether” is mentioned, most people think of the well-known anesthetic,
diethyl ether. There are many ethers. Their uses range from artificial flavorings to refrig-
erants and solvents. An etheris a compound in which an O atom is bonded to two organic
groups.

Alcohols are considered derivatives of water in which one H atom has been replaced by
an organic group. Ethers may be considered derivatives of water in which both H atoms
have been replaced by organic groups.

HXOXHRXOXHRXOXR

water alcohol ether

The similarity is only structural, however, because ethers are only slightly polar and are
chemically rather unreactive. In fact, their physical properties are similar to those of the
corresponding alkanes; for example, CH 3 OCH 3 is like CH 3 CH 2 CH 3.
Three kinds of ethers are known: (1) aliphatic, (2) aromatic, and (3) mixed. Common
names are used for ethers in most cases.

C O C

27-10

Fermentationis an enzymatic process

carried out by certain kinds of bacteria.

27-10 Ethers 1071

H 3 C O CH 3

methoxymethane

dimethyl ether

(an aliphatic ether)

H 3 C O CH 2 CH 3

methoxyethane

methyl ethyl ether

(an aliphatic ether)

methoxybenzene

methyl phenyl ether

anisole

(a mixed ether)

phenoxybenzene

diphenyl ether

(an aromatic ether)

O CH 3 O

When the benzene ring is a

substituent, it is called a phenyl group

(XC 6 H 5 ).

Models of diethyl ether (top) and

methyl phenyl ether (bottom).