On the differences in the mechanisms of reduction of AuCl2 - And Ag(H2O)2 + with BH4

The mechanism of reduction of AuCl4 -/AuCl3OH- by BH4 - was analyzed by density functional theory (DFT). The results point out that Auatoms 0 are not intermediates in the process. The derived mechanism differs considerably from that reported for the analogous process involving the reduction of Ag(H2O)2 + by BH4 -. Thus, though both processes follow the Creighton procedure, the detailed mechanism differs significantly. For Au, the agglomeration starts with AuH2 -, whereas for Ag, it starts with (H2O)AgH. Stopped-flow measurements support the complicated mechanism.