[fatroro]

I have some questions about this preparation.

What is the underlying principle of the preparation of 2-chloro-2-methylpropane from 2-methylproan-2-ol and hydrochloric acid?

Why should we use the simple distillation to obtain the product?

Why is the SN1 substitution favoured in this reaction?

thz for answering =]

[T-rex]

1.  Electrons from the H on the HCl get dumped on to the chlorine. That hydrogen gets grabbed by the alcohol. This forms a leaving group (water), and a tertiary carbocation (Sn1). The Nucleophilic Chlorine attacks the carbocation (electrophilic) from either orientation of the molecule not just the backside (Sn1). Leaving you with a final product that is a racemic mixture.

2. Simple distillation is only used when products in a mixture have very high boiling point differences. 
2-chloro-2-methylpropane = 51 C
2-methylproan-2-ol = 83 C

Simple distillation to separate is feasible.


3. answered above.