Models for Bimetallic Catalysts: Multiple Oxidation States in Pt_3Re Cluster Cations

摘要

Binding between oxo ligands and the small metal clusters present in the important oxide-supported bimetallic Pt-Re catalysts may occur at the metal-support interface and also during oxidation-reduction cycles. However, knowledge of how oxygen interacts with the metal clusters in limited due to the diffficulties in characterizing the heterogeneous materials. There are also few related metal oxo clusters to act as model compounds. The oxidation of 1 (Dppm=Ph_2PCH_2PPh_2) with Me_3NO or oxygen to give the 2 and 3, respectively, was reported earlier. Here we show that further oxidation of 3 to give the novel clusters 4-6 is possible (Scheme 1).