Synthesis and interconversions of dinuclear iron complexes with .mu.-methyl, .mu.-methylene, and .mu.-methylidyne ligands

Organometallic Models for Metal Surface Reactions: Chain Growth Involving Electrophilic Methylidynes in the Fischer–Tropsch Reaction

“…Related facile reactions forming C-C bonds have been shown to occur for cationic l-methylidyne-di-ruthenium and -di-iron complexes [24][25][26][27][28], as for example the reaction with the C 1 source, diazomethane,…”

CC Bond Formation in Diiron Complexes

“…, which was obtained by Casey upon hydride abstraction from the corresponding methylidene com- [9] and by Pettit through OMe abstraction from […”

“…Pioneering work of Hubel and Weiss [53] evidenced that reactions of [Fe 2 (CO) 9 ] with alkynes afford carbonyl-containing cyclic organic products, including, for example, pentadienones and cycloheptatrienone (tropone). [54] The mechanism of the assembly of alkynes with CO remains rather obscure, although it is reasonable to assume involvement of diiron organometallic intermediates.…”

“…In general, μ‐alkylidynes are electrophilic species and can undergo nucleophilic addition to form the corresponding alkylidene (carbene) complexes; in the case of carbon nucleophiles, this provides a valuable route to CC bond formation. One of the most representative example is the bridging methylidyne complex [Fe 2 (μ‐CH)(μ‐CO)(CO) 2 (Cp) 2 ][PF 6 ] (Cp=η 5 ‐C 5 H 5 − , 1 ), which was obtained by Casey upon hydride abstraction from the corresponding methylidene complex [Fe 2 (μ‐CO)(μ‐CH 2 )(CO) 2 (Cp) 2 ] ( 2 )9 and by Pettit through OMe abstraction from [Fe 2 (μ‐CO)(μ‐CHOMe)(CO) 2 (Cp) 2 ] ( 3 ) 10. It has to be remarked that mononuclear methylidyne complexes (L n MCH) are relatively rare, in that the classical Fischer carbyne (L n MCR) synthesis11a and subsequent Mayr modification11b–c require the introduction of the ultimate substituent “R” through nucleophilic attack at a metal carbonyl, which limits the range of R substituents mostly to alkyl, aryl and alkenyl groups.…”

Platinum–alkyl–B(C6F5)3 (or BF3) ‘in situ’ systems as tin(II) halide-free enantioselective hydroformylation catalysts

“…The most common ways of metals being bridged by methyl groups are the (almost) symmetrically bridged geometry (A) [30,31] involving a threecentre M-C-M interaction, and the asymmetrically bridged agostic geometry (B), in which the methyl carbon is r-bound to one metal while being involved in a threecentre M-C-H agnostic interaction with the second metal (Scheme 2). For late transition metal complexes geometry B is far more common [32,33].…”