Answer to Question #166403 in Organic Chemistry for Hafiz Faizal

Question

a) Give the structure of an alkene (or alkenes) with the same number of carbon atoms for the synthesis of the following alcohols:

(i) Butan-2-ol

(ii) 1-Methylcyclohexanol

(iii) tert-butylalcohol

(iv) 1-Methylcyclopentanol

(v) 2-Methylpropan-2-ol 

(b) Write the mechanism for the sulfuric acid catalyzed dehydration of alcohols in 2. (a) (ii) & (iii) and state the rule that determines the products of the reaction. 

Answer 1

During dehydration of secondary and tertiary alcohols, hydrogen is eliminated mainly from the least hydrogenated carbon atom.