Synthetic Applications of Stryker’s Reagent

Abstract

Hexa-m-hydrohexakis(triphenylphosphine) hexacopper, also known as Stryker’s reagent, is a well-characterized copper(I) hydride reagent for chemoselective conjugate reduction of a,b-unsaturated ketones, [1-7] esters, [1] [4] lactones, [8] nitriles, [9] aldehydes, [3] sulfones, and sulfonates. [6] The reaction is highly chemoselective, and isolated alkenes, halogens, and typical oxygenated functionalities are not reduced under the reaction conditions. [1-7] In the presence of several silanes and a catalytic quantity of Stryker’s ­reagent, ketones and aldehydes are reduced to the corresponding alcohols. [10] The conjugated reduction can be performed either stoichiometrically or catalytically in the presence of reducing agents, and the reaction intermediates can be used for further C-C bond formations. [9] [11-14] Stryker’s reagent is commercially available, but various methods have been developed over the years for its preparation. [15-19]