Reaction of 3-chloro-2-(trimethylsiloxy)prop-1-ene with low-valent metal complexes. Syntheses of metallacyclobutan-3-ones of osmium, iridium, and platinum and the X-ray structure of chloro(carbonyl)bis(triphenylphosphine)iridacyclobutan-3-one

The low-valent metal complexes, [IrH(CO)(PPh3)3], [Pd(PPh3)4], and [Pt(trans-stilbene)(PPh3)2] catalyse the isomerisation of the ketone Me3SiCH2C(O)CH2Cl to the silylenol ether CH2C(OSiMe3)CH2Cl which reacts with [Os(CO)2(PPh3)3], [IrH(CO)(PPh3)3], [IrH(CO)2(PPh3)2], trans-[IrCl(CO)(PPh3)2], and [Pt(trans-stilbene)(PPh3)2] to afford the metallacyclobutan-3-ones [[graphic omitted]H2}(CO)2(PPh3)2], [[graphic omitted]H2}(Cl)(CO)(PPh3)2] and [[graphic omitted]H2}(PPh3)2]; the X-ray structure of the title complex (3) establishes the presence of a puckered iridacyclobutan-3-one ring [fold angle 41°].