Synthesis and Reactivity of New (Methoxy)methyl Complexes of Manganese(I) and Rhenium(I)

The reactions of Na[M(CO)3(bipy)] (M = Mn, Re) with ClCH2OCH3 afford the (methoxy)methyl complexes [M(CH2OCH3)(CO)3(bipy)] (M = Mn, 1; Re, 2), characterized by IR and NMR spectroscopy and, in the case of 1, also by X-ray diffraction. Highly electrophilic species, presumably cationic alkylideneoxonium complexes, although they were not detected, were prepared in situ by reaction of 1 and 2 with methyl triflate. These species react with neutral nucleophiles such as SMePh to generate the alkylidenesulfonium complexes [M(CH2SPhMe)(CO)3(bipy)]+[OTf]- (M = Mn, 3; Re, 4) and with styrene to give phenylcyclopropane and the corresponding triflate complexes [M(OTf)(CO)3(bipy)].