TRIOSMIUM CLUSTERS WITH MU-3-ASR GROUP AS A BUILDING BLOCK FOR HEXAOSMIUM-ARSENIC CLUSTER SYNTHESIS - SYNTHESIS AND CHARACTERIZATION OF [(CO)11OS3AS(OS3(CO)9H3)] AND [(CO)9H3OS3AS(OS3(CO)9H3)] - CRYSTAL-STRUCTURE OF [(CO)11OS3AS(OS3(CO)9H3)]

Reaction of the activated cluster [Os3(CO)11(NCMe)] with primary arsine AsH3 forms the arsinidine compound [H2Os3(mu-3-AsH)(CO)11] (1a, 1b), which on further reaction with [Os3(CO)11(NCMe)] yields [(CO)11Os3As(Os3(CO)9H3)] (2) and with [H2Os3(CO)10] yields [H2Os3(CO)9As(Os3(CO)9H3)] (3). Similarly [H2Os3(CO)10] reacts with AsH3 at room temperature to afford 3 in good yields. Thermal degradation and rearrangement of 2 gives the pentanuclear cluster [H2Os5(CO)17AsH] (4).