Phase-transfer catalyzed glycolate conjugate addition

Cinchonine based phase-transfer catalysts were developed for enantioselective conjugate additions to electron deficient alkenes, including acylates, acrylonitrile, and chalcone. N-Trifulorobenzyl cinchoninium bromide 6 catalyst (20 mol %) in THF at −40 °C promoted the conjugate addition of arylketone glycolate 1 generating S-product 2 in good yields and selectivities. Catalyst, solvent, and base variations are presented along with conditions to convert the products to intermediates useful for multistep applications.

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