Reactivity of [Cp*Mo(CO)₃Me], 1 with various chalcogenide ligands such as Li[BH₂E₃] andLi[BH₃EFc]] (E = S, Se or Te; Fc = (C₅H₅-Fe-C₅H₄)) has been described. Room temperature reaction of 1 with Li[BH₂E₃] (E = S and Se) yielded metal chalcogenide complexes [Cp*Mo(CO)₂(ŋ2-S₂CCH3)], 2 and [Cp*Mo(CO)₂(ŋ1-SeC₂H₅)], 3. In compound 2, {Cp*Mo(CO)2} fragment adopts a four-legged piano-stool geometry with a η2-dithioacetate moiety. In contrast, treatment of 1 with Li[BH3(EFc)] (E = S, Se or Te; Fc = C₅H₅-Fe-C₅H₄) yielded borate complexes [Cp*Mo(CO)₂(μ-H)(μ-EFc)BH₂], 4-6 in moderate yields. Compounds 4-6 are too unstable and gradual conversion to [{Cp*Mo(CO)₂}₂(μ-H)(μ-EFc] (7: E = S; 8: Se) and [{Cp*Mo(CO)₂}₂(μ-TeFc)₂], 9 happened by subsequent release of BH₃. All the compounds have been characterized by mass spectrometry, IR, multinuclear NMR spectroscopy and structures were unequivocally established by crystallographic analysis for compounds 2, 3 and 7.
