A Manual of the Chemistry of the Carbon Compounds

86 TEE OHEMTSTRY OF
(2) SECONDARY ALCOHOLS AND KETONES.
In the secondary alcohols the group OH is linked to a carbon atom,
itself combined with two other atoms of carbon. The lowest member
in the series contains consequently three atoms of carbon, and is the
secondary propjl alcohol or dimethyl carbinol:—
CH8 C
CH.OH OH = £*[» £*[ 1CH.OH
This body may be regarded as methyl alcohol in which two hydrogen
atoms are substituted by methyl, and has therefore received the
name dimethyl carbinol, the term carbinol being used for methyl
alcohol in order to avoid such cumbrous terms as dimethylated
methyl alcohol, &c.
Secondary alcohols are formed by several general reactions:—
(1) On acting with chlorine upon the paraffins there is always a
mixture of a primary and a secondary chloride formed at the same
time.
(2) All alcohols of polygenic radicals yield, on heating them with
an excess of concentrated hydriodic acid, secondary iodides. Thus
mannite COH8(OH)O is converted by this reaction into a secondary
hexyl iodide:—
C6H8(OH)O + 11HI » C6H18I + 6H2O + 61,
(3) The hydrocarbons of the series CJS^ combine directly with
the hydraeids forming secondary chlorides, bromides, or iodides:—
OH, CHS
CH + HI - CHI
II I
0H2
CH3
From those chlorides, &c, the alcohols are obtained by the same
reactions by which the primary chlorides are converted into alcohols.
The secondary alcohols, as well as their haloid ethers, differ from
the primary compounds by being much more easily resolved into an
define and water or a hydracid. Both groups, however, are most
readily distinguished by their products of oxidation. The secondary
alcohols lose in the first instance, like the primary alcohols, two
atoms of hydrogen, but the compound thus formed is not an aldehyde
but an acetone or ketow;—•