Reaction of Os₃(CO)₉(μ₃-η²-C₇H₃(2-CH₃)NS)(μ-H) with Diazomethane. The First Example of a Trimetallic Cluster Containing a μ-Methylidene and a σ-Methyl

The electronically unsaturated cluster Os3(CO)9(μ3-η2-C7H3(2-CH3)NS)(μ-H) (6) reacts with excess CH2N2 at −10 to +25 °C to give Os3(CO)9(μ-η2-C7H3(2-CH3)NS)(μ-CH2)CH3 (9), a rare example of a triosmium cluster containing an edge-bridging methylene group and a σ-bound methyl group. On thermolysis in refluxing heptane 9 affords Os3(CO)9(μ3-η2-CHC7H3(2-CH3)NS)(μ-H)2 (11) and Os3(CO)8(μ3-η2-CC7H3(2-CH3)NS)(μ-H)3 (12). In contrast, Os3(CO)8(μ3-η2-C7H4NS)(μ-H)(7) reacts with diazomethane under exactly similar conditions to afford Os3(CO)9(μ3-η2-CHC7H4NS)((μ-H)2 (10), which on thermolysis in refluxing heptane gives Os3(CO)8(μ3-η2-CC7H4NS)(μ3-H)3 (13).