Dual platinum and pyrrolidine catalysis in the direct alkylation of allylic alcohols: Selective synthesis of monoallylation products

A dual platinum- and pyrrolidine-catalyzed direct allylic alkylation of allylic alcohols with various active methylene compounds to produce products with high monoallylation selectivity was developed. The use of pyrrolidine and acetic acid was essential, not only for preventing undesirable side reactions, but also for obtaining high monoallylation selectivity. Two cats are better than one: The combined use of platinum and pyrrolidine catalysts enabled the direct alkylation of allylic alcohols with reactive methylene compounds. Pyrrolidine was essential for obtaining high selectivity of the monoallylation products, which were produced without the use of excess nucleophiles. cod=1,5- cyclooctadiene, EWG=electron-withdrawing group.