The remarkable role of steric factors in the reactions of alkynes (HCCH and MeCCMe)with ditungsten hexa-alkoxides: crystal and molecular structures of W2(OPri)6(py)2(µ-C2H2), W2(OCH2But)6(py)2(µ-C2Me2), and W2(OPri)6(µ-C4R4)(C2R2), where R = H and Me (py = pyridine)

Abstract

Ethyne and but-2-yne react with hydrocarbon solutions of W₂(OR)₆ compounds in the presence of pyridine (py) to produce the compounds W₂(OR)₆(py)₂(µ-C₂R′₂), W₂(OR)₆(η-C₄R′₄)(C₂R′₂), or R′CW(OR)₃, depending on the nature of the alkoxy group and the alkyne substituent, R′