Question

The reaction of $SOC{{l}_{2}}$ on alcohols to alkyl chlorides gives good yields because:
A. alkyl chlorides are immiscible with $SOC{{l}_{2}}$.
B. The products of the reaction are gaseous and escape out.
C. Alcohol and $SOC{{l}_{2}}$ are soluble in water.
D. The reaction does not occur via intermediate formation of an alkyl chlorosulfite.

Answer 1

We know that the reaction of alcohols to alkyl chloride in $SOC{{l}_{2}}$ gives nucleophilic substitution reactions. This substitution reaction depends upon the type or degree of alkanols.

Complete answer:
$SOC{{l}_{2}}$ is also known as thionyl chloride. Thionyl chloride is primarily used as a chlorinating reagent. It is toxic and reacts with water. In this reaction hydroxide of alkanol is substituted by chlorine of thionyl chloride. Below given is the reaction of alkanols with $SOC{{l}_{2}}$ :

Here Hydrogen chloride ($HCl$) and sulphur dioxide ($S{{O}_{2}}$) are in gaseous form and they continuously escape out. So, there is no alternate product other than alkyl chloride. So, we get a good yield of the wanted product in this mechanism. There are different types of substitution reactions with different solvents for this type of conversion.

So, the correct answer for the good yield is option “B”.

Note: Thionyl chloride is sometimes confused with sulfuryl chloride, $SO_2C{{l}_{2}}$, but the properties of these compounds differ significantly. And the mechanism of this reaction depends on the degree of alcohol.