Enzymes in organic synthesis. 27. Lipase??Catalyzed Synthesis of (5R, 6S)??6??Acetoxyalkan??5??olides–homologues of the mosquito oviposition attractant pheromone
Abstract Sixteen homologous (5R*, 6S*)-6-hydroxyalkan-5-olides rac-5 and their acetoxy derivatives rac-6 were synthesized from the corresponding methyl (Z)-alk-5-enoates 3 by osmium (VIII) oxide catalyzed cis-hydroxylation to the dihydroxy esters rac-4 and hydrolysis of these esters followed by lactonization. Pancreatin-catalyzed lactonization of the dihydroxy esters rac-4 afforded enantiomerically enriched hydroxy lactones ent-5, five of which were ...
