Bimetallic activation of coordinated ligands. Reactions of the Lewis acid (η-C5H5)(CO)3Mo+ PF6− with organo-iron and -molybdenum η1-methoxymethyl and ethyl complexes

Carbon monoxide and carbon dioxide fixation: relevant C1 and C2 ligand reactions emphasizing (.eta.5-C5H5)Fe-containing complexes

“…Other fully characterized methoxymethylenes prepared by similar reactions include Cp*(CO)2M=CH(OCH3)+PF6" (M = Fe, Ru),161 Cp(PPh3)(NO)Re=CH(OCH3)+OTF,38 and Cp(CO)3Mo=CH(OCH3)+PF6-. 162 In contrast, Cp-(PPh3)(CO)2Mo-CH2OCH3 affords the parent methylene salt under similar conditions. 163 Lapinte and co-workers monitored the reactions between the iron and ruthenium methoxymethyl complexes Cp*(CO)2M-CH2OCH3 and Ph3C+PF«f.161b Both reactions occur instantaneously at -78 °C and produce mixtures of two geometric isomers, the anti-cis kinetic and the anti-trans thermodynamic products [in 90:10 (M = Fe) and 95:5 (M = Ru) ratios, respectively].…”

“…Beck's Lewis acid Cp(CO)3Mo+PF6" (53PF6_) competitively abstracts both hydride and alkoxide from the methoxymethyl complex Cp(CO)3Mo-CH2OCH3 (71). 162 The observed products, depicted in Scheme 15, are methoxymethylene 72, /2-hydride 57, and m-(»?2-C,0)acetyl 56. Methoxide abstraction from 71 gives the methylene intermediate 70, whereas hydride abstraction produces Cp(CO)3Mo-H and 72.…”