método de preparação de ésteres cílicos a partir de compostos com cinco ou seis carbonos que compreende o contato de um leito que contém um catalisador ácido sólido com pelo menos um dentre um composto com cinco ou seis carbonos e método de preparação de ésteres cíclicos com compostos com cinco ou seis carbonos que compreende, irradiando com micro-ondas, uma mistura líquida de um catalisador ácido inorgânico, ácido orgânico e pelo menos um composto com cinco ou seis carbonos

摘要

Described herein are improved methods for the preparation of 5- and 6-membered cyclic mono and diesters of sugar alcohols and anhydrosugar alcohols by reaction with an organic acid RCOOH over a solid acidic substrate. The process is adaptable to a continuous process for simultaneously making and separating the cyclic esters from the sugar alcohols and anhydrosugar alcohols under mild conditions using the solid acid substrate as both the catalyst and a chromatographic bed for separation. The reactions are performed at mild temperatures of 70° C. to 100° C. and the formation of the cyclic esters is nearly quantitative. Also described is a method for making 5- and 6-membered cyclic mono and diesters of sugar alcohols and anhydrosugar alcohols using microwave irradiation in the presence of the organic acid.