ELECTRON-TRANSFER PROPERTIES OF POTASSIUM TETRACHLOROAURATE(III), GOLD(I) TRIALKYLPHOSPHINE, AND GOLD(I) TRIALKYL PHOSPHITE COMPLEXES IN NONAQUEOUS MEDIA

An electrochemical and spectroelectrochemical investigation of Au[P(R)3]Cl, where R = C2H5, C6H5, OC2H5, and OC6H5, and Au[P(R)3]2Cl, where R = C6H5 and OC2H5, in acetonitrile (CH3CN), tetrahydrofuran (THF), or dichloromethane (CH2C12) with tetrabutylammonium perchlorate (TBAP) as supporting electrolyte is presented. The experiments were performed in the absence of both water and oxygen, and under these conditions, the gold(I) complexes are oxidized by a ECE(C) process to generate [AuX4]-, X = Cl- and Cl04-. Reduction of [AuX4]- in the presence of P(R)3 results in regeneration of Au[P(R)3]Cl. The potential for the oxidation of Au[P(R)3]Cl and Au[P(R)3]2+ is dependent upon the nature of the ligands and the solvent conditions. Electrochemical data for K[AuCl4] are also presented and are consistent with an electron-transfer mechanism previously proposed for the reduction of H[AuCl4]. By the use of electrochemical, spectroelectrochemical, and conductivity data, an electron-transfer mechanism for the gold species is presented. © 1990, American Chemical Society. All rights reserved.