1-Ethylpiperidium Hypophosphite: A Practical Mediator for Radical Carbon-Carbon Bond Formation

Enantioselective radical addition reactions to the CN bond utilizing chiral quaternary ammonium salts of hypophosphorous acid in aqueous media

An enantioselective addition of alkyl radicals to glyoxylate oxime ether mediated by Cinchona alkaloid derived chiral ammonium salts of hypophosphorous acid, QP and QDP, has been developed.

Diethylphosphine oxide (DEPO): high-yielding and facile preparation of indolones in water

[reaction: see text] Indolones are prepared in excellent yield at 80 degrees C in water by radical reaction (aryl radical formation, hydrogen atom abstraction, cyclization, and rearomatization) mediated by the reagent diethylphosphine oxide (DEPO). The reaction features V-501 as a water-soluble initiator; no other additives are needed. The process proceeds at a much lower temperature than is required for efficient reaction with toxic tributyltin hydride in benzene and permits significantly higher isolated yields than the corresponding reaction mediated by ethylpiperidine hypophosphite (EPHP).