Reaktionen von dreikernigen schwefelverbrückten Carbonyleisen-Clustern mit Alkinen

The compound Fe₃(CO)₉(μ₂-H)(μ₃-S^tBu) (1) reacts with PhCCPh upon photochemical activation under elimination of one CO group to give Fe₃(CO)₈(η²-μ₂-HPhCCPh)(μ₃-S^tBu) (2). In contrast, the thermally initiated reaction of Fe₃(CO)₉(μ₂-Cl)(μ₃-S^tBu) (3) with HCCPh results in fragmentation, yielding the binuclear products {A figure is presented} (4) and Fe₂(CO)₆(η²-μ₂-H₂CCPh)(μ₂-S^tBu) (5. A simple preparative route to compounds 4 and 5 by the one-pot reaction of Fe₂(CO)₉ or Fe₃(CO)₁₂ respectively, with ^tBuSH and HCCPh is reported. The preparation, properties and structures of the products 2, 4, 5 and of the substitution derivative of 5, Fe₂(CO)₄(P(OMe)₃)₂(η²-μ₂-H₂CCPh)(μ₂-S^tBu) (6) as well as of the byproducts from the one-pot synthesis, Fe₂(CO)₅(η²-μ₃-^tBuSCPh=CHCO)(μ₂-S^tBu) (7 and {A figure is presented} (8) are discussed. The structures of compounds 2, 4, 5, 6 and 8 are best described as π-complexes of hetero-organometallic ligands.