Tert-Butyl chloride


tert-Butyl chloride is the organochloride with the formula 3CCl. It is a colorless, flammable liquid. It is sparingly soluble in water, with a tendency to undergo hydrolysis to the corresponding tert-butyl alcohol. It is produced industrially as a precursor to other organic compounds.

Synthesis

tert-Butyl chloride is produced by the reaction of tert-butyl alcohol with hydrogen chloride. In the laboratory, concentrated hydrochloric acid is used. The conversion entails a SN1 reaction as shown below.
Step 1
Step 2
Step 3
The acid protonates the alcohol, forming a good leaving group.
Water leaves the protonated t-BuOH, forming a relatively stable tertiary carbocation.
The chloride ion attacks the carbocation, forming t-BuCl.

The overall reaction, therefore, is:
Because tert-butanol is a tertiary alcohol, the relative stability of the tert-butyl carbocation in the step 2 allows the SN1 mechanism to be followed, whereas a primary alcohol would follow an SN2 mechanism.

Reactions

When tert-butyl chloride is dissolved in water, it undergoes a hydrolysis to tert-butyl alcohol. When dissolved in alcohols, the corresponding t-butyl ethers are produced.

Uses

tert-Butyl chloride is used to prepare the antioxidant tert-butylphenol and the fragrance neohexyl chloride.