[EN] DEHYDRATIVE CYCLIZATION OF PENTITOLS USING WATER-TOLERANT LEWIS ACID CATALYSTS UNDER MILD CONDITIONS AND DERIVATIVES<br/>[FR] CYCLISATION PAR DÉSHYDRATATION DE PENTITOLS À L'AIDE DE CATALYSEURS DE TYPE ACIDE DE LEWIS TOLÉRANTS À L'EAU DANS DES CONDITIONS DOUCES, ET DÉRIVÉS CORRESPONDANTS
申请人:ARCHER DANIELS MIDLAND CO
公开号:WO2017030684A1
公开(公告)日:2017-02-23
A catalytic process for the dehydrative cyclization of pentitols to synthesize anhydropentitols is described. Water-tolerant Lewis acids (in particular, metal triflates) are employed as catalysts to improve conversion and anhydropentitol selectivity at ultra-low catalyst loadings. The process can produce cyclic ether triols in high yields with concurrent complete pentitol conversion.
Methanesulfonyl chloride in N,N-dimethylformamide transformed unprotected D-arabinitol into its 1,5-dichloro derivative in 50% yield. Other pentitols also reacted to give the corresponding 1,5-dichloropentitols, but with lower yields. The structures of the products were determined by n.m.r. spectroscopy.