Reactions of 1-Hydroxypyridine-2-thione with Triosmium Clusters. Preparation and Transformation of N-Oxide-Containing Osmium Complexes

Abstract

The reaction of 1-hydroxypyridine-2-thione with Os3(CO)11(NCMe) has yielded three new complexes Os3(CO)10(μ-H)(μ-η1-S-C5H4N(O)) (1, 11% yield), Os3(CO)10(μ-H)(η2-S-C5H4N(O)) (2, 16% yield), and Os3(CO)9(μ-H)(μ-η2:η1-SC5H4N(O)) (3, 3% yield). Similarly, treatment of complex Os3(CO)10(NCMe)2 with this ligand has produced the major complexes 1 and trace of 3. Prolonging the above two reactions increased the yield of 3. Treatment of 1-hydroxypyridine-2-thione with triosmium isocyanide complexes Os3(CO)10(CNR)(NCMe) (a, R = CH2Ph; b, R = Pr) has led to the formation of Os3(CO)9(μ-H)(CNR)(η2-SC5H4N(O)) (4), Os3(CO)10(μ-η1-CNHCH2Ph)(μ-η1-S-C5H4N(O)) (5), and Os3(CO)9(μ-H)(CNR)(μ-η1-S-C5H4N(O)) (6). The 4:5 ratio depended upon the nature of the alkyl groups of the coordinated isocyanide. Reaction of either 1 or 2 with Me3NO resulted in CO loss and formation of complex 3. Thermolysis of 1 at 80 °C generated Os3(CO)9(μ-H)(μ3-pyS) (7), Os3(CO)9(μ-OH)(μ3-pyS) (8), and byproduct CO2. Upon being heated at 80 °C, 3 was ...