Montmorillonite-Catalyzed Substitution Reactions of Alcohols

Significance

Nucleophilic substitution reactions of alcohols in the presence of montmorillonites as solid Brønsted acids were developed. Thus, the reactions of secondary alcohols with amines, indoles, 1,3-dicarbonyl compounds and allyl silanes (1.5-2 mol equiv) were performed with proton-exchanged montmorillonite (H-mont) (1.7-17 mol%) to give the corresponding products in trace to 99% yield. The reaction of benzylic primary alcohols with 1,3-diketones was also carried out with Al-mont in place of H-mont to give the corresponding products in 65-83% yield (three examples).