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.