Reactivity of [Cp*Mo(CO)3Me] with chalcogenated borohydrides Li[BH2E3] and Li[BH3EFc] (Cp* = (η5-C5Me5); E = S, Se or Te; Fc = (C5H5-Fe-C5H4))

Reactivity of [Cp*Mo(CO)(3)Me], 1 with various chalcogenide ligands such as Li[BH2E3] and Li[BH(3)EFc] (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)(eta(2)-S2CCH3)], 2 and [Cp*Mo(CO)(2)(eta(1)-SeC2H5)], 3. In compound 2, {Cp*Mo(CO)(2)} fragment adopts a four-legged piano-stool geometry with eta(2)-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)(mu-H)(mu-EFc)BH2], 4-6 in moderate yields. Compounds 4-6 are too unstable and gradual conversion to [{Cp*Mo(CO)(2)}(2)(mu-H)(mu-EFc] (7: E = S; 8: Se) and [{Cp*Mo(CO)(2)}(2)(mu-TeFc)(2)], (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.