Ruthenium carbonyl cluster complexes with oxygen ligands. Part 2. Auration of a hexaruthenium 'raft' cluster; Crystal structures of [Ru6(μ3-H)(μ-H)(μ-O:μ-C:η 6-OC6H3OMe-4)(CO)16] and [AuRu6(μ3-H)(μ-O:μ-C:η6-OC 6H3OMe-4)(CO)16...

Abstract

Full title: Ruthenium carbonyl cluster complexes with oxygen ligands. Part 2. Auration of a hexaruthenium 'raft' cluster; Crystal structures of [Ru6(μ3-H)(μ-H)(μ-O:μ-C:η 6-OC6H3OMe-4)(CO)16] and [AuRu6(μ3-H)(μ-O:μ-C:η6-OC 6H3OMe-4)(CO)16(PPh3)]. The hexaruthenium raft cluster [Ru6(μ3-H)(μ-H)(μ-O:μ-C:η 6-OC6H3OMe-4)(CO)16] 1 is smoothly deprotonated by K-Selectride {K[B(CHMeEt)3H] in tetrahydrofuran}, the resulting cluster anion being aurated by [AuCl(PPh3)] to afford the mixed-metal cluster [AuRu6(μ3-H)(μ-O:μ-C:η6-OC 6H3OMe-4)(CO)16(PPh3)] 2 as the major product in moderate yield. The crystal structures of both 1 and 2 have been determined. The structural studies have revealed that isostructural replacement of H by isolobal Au(PPh3) has not occurred; rather, an edge-bridging hydride has been replaced by a face-capping (phosphine)aurio moiety. In an analogous fashion to the auration, sequential reaction of 1 with K-Selectride and H3PO4 regenerated 1. By contrast, hydrogenation [1 atm (ca. 105Pa) H2, refluxing cyclohexane] of 1 resulted in expulsion of the -OC6H3OMe-4 ligand and formation of [Ru4(μ-H)4(CO)12]. Show more