Cellulose-SO3H as a recyclable catalyst for the synthesis of tetrahydropyranols via Prins cyclization
摘要:
Tetrahydropyranols are prepared in good yields and with high cis-selectivity by means of the Prins cyclization using cellulose-sulfonic acid under mild reaction conditions. This is the first report on the preparation of tetrahydropyranols using epoxides and homoallylic alcohols via Prins cyclization. (C) 2010 Elsevier Ltd. All rights reserved.
Phosphomolybdic acid (H3PMo12O40, a heteropoly acid) is found to catalyze efficiently the Prins cyclization of homoallylic alcohols with aldehydes in water at room temperature to provide tetrahydropyran-4-ol derivatives in high yields with all cis-selectivity. Only cyclic ketones can give spirocyclic products. The use of phosphomolybdic acid in water makes this procedure simple, more convenient, cost-effective, and environmentally friendly.
Tetrahydropyranols are prepared in good yields and with high cis-selectivity by means of the Prins cyclization using cellulose-sulfonic acid under mild reaction conditions. This is the first report on the preparation of tetrahydropyranols using epoxides and homoallylic alcohols via Prins cyclization. (C) 2010 Elsevier Ltd. All rights reserved.