Asymmetric phase-transfer alkylation catalyzed by a chiral quaternary phosphonium salt with a multiple hydrogen-bonding site

Article abstract of DOI:10.1016/S0040-4039(98)01181-2

A chiral phosphonium salt has been synthesized as a novel phase- transfer catalyst, and used for asymmetric benzylation of t-butyl 2- oxocyclopentanecarboxylate to give the corresponding product with up to 50% ee.