Synthesis and characterization of binuclear μ-oxo and μ-telluro molybdenum(V) complexes, [Cp^∗Mo(O)(μ-Te)]₂

Abstract

Pyrolysis of an in-situ generated intermediate, produced in the reaction of [Cp^∗MoCl₄], 1, (Cp^∗ = η⁵-C₅Me₅) with [LiBH₄·THF], with an excess of difuryl ditelluride in toluene at 90 °C yielded syn and anti isomers of [Cp^∗Mo(O)(μ-Te)]₂ (2, 3) and [Cp^∗₂Mo₂O₂ (μ-O)(μ-Te)] (4, 5). In a similar fashion, dibenzyl diselenide yielded syn and anti isomers of [Cp^∗Mo(O)(μ-Se)]₂ (6, 7), along with the known nido-[(Cp^∗Mo)₂B₄H₈Se₂]. Note that in parallel with 2–7, [(Cp^∗Mo)₂B₅H₉] was isolated as the major product in both cases. Compounds 2–7 have been isolated in modest yield as orange to brown crystalline solids. All the new compounds have been characterized in solution by mass, IR, ¹H, ¹¹B, ¹³C, ⁷⁷Se, ¹²⁵Te NMR spectroscopy, and the structural types were unequivocally established by crystallographic analysis of 2–4 and 7.