2-D Molecular Alloy Ru-M (M = Cu, Ag, and Au) Carbonyl Clusters: Synthesis, Molecular Structure, Catalysis, and Computational Studies.

The reactions of [HRu 3 (CO) 11 ] - ( 1 ) with M(I) (M = Cu, Ag, and Au) compounds such as [Cu(CH 3 CN) 4 ][BF 4 ], AgNO 3 , and Au(Et 2 S)Cl afford the 2-D molecular alloy clusters [CuRu 6 (CO) 22 ] - ( 2 ), [AgRu 6 (CO) 22 ] - ( 3 ), and [AuRu 5 (CO) 19 ] - ( 4 ), respectively. The reactions of 2-4 with PPh 3 result in mixtures of products, among which [Cu 2 Ru 8 (CO) 26 ] 2- ( 5 ), Ru 4 (CO) 12 (CuPPh 3 ) 4 ( 6 ), Ru 4 (CO) 12 (AgPPh 3 ) 4 ( 7 ), Ru(CO) 3 (PPh 3 ) 2 ( 8 ), and HRu 3 (OH)(CO) 7 (PPh 3 ) 3 ( 9 ) have been isolated and characterized. The molecular structures of 2-6 and 9 have been determined by single-crystal X-ray diffraction. The metal-metal bonding within 2-5 has been computationally investigated by density functional theory methods. In addition, the [NEt 4 ] + salts of 2-4 have been tested as catalyst precursors for transfer hydrogenation on the model substrate 4-fluoroacetophenone using i PrOH as a solvent and a hydrogen source.