“…Recently, we reported the first triosmium clusters containing an ancillary sac ligand from the reactions of [Os3(CO)10-n(NCMe)n] (n = 1, 2) with sacH in refluxing benzene. Scheme 1 illustrates the reaction that gives [HOs3(CO)10(μ-N,O-1,2-sac)], whose reactivity with monodentate phosphines, PR3 (R = Ph, Th, Fu) was examined in our report and found to afford the corresponding mono-and bis-phosphine substituted derivatives [HOs3(CO)9(PR3)(μ-N,O-1,2-sac)] and [HOs3(CO)8(PR3)2(μ-N,O-1,2-sac)], respectively [19]. The coordinated sac ligand maintains a μ-N,O coordination mode in the products and is believed to play a pivotal role as a spectator ligand that helps to direct the phosphine regiochemistry associated with these substitution reactions.…”