Communications - Acyl Manganese Pentacarbonyl Compounds

Abstract

We wish to report the first alkyl derivatives of a metal carbonyl. Previous authors have reported the synthesis of cyclopentadienyl metal carbonyls1 and alkyl derivatives thereof2 3as well as acetylene and aliene corhplexes of metal carbonyls,8•4 ***but we know of no previous report of stable alkyl metal carbonyls.Manganese carbonyl dissolved in tetrahydrofuran was smoothly converted to a solution of NaMn(CO)6 when treated with an excess of 1% sodium amalgam or finely divided sodium in an inert atmosphere. This solution, maintained in the inert atmosphere, was decanted from excess sodium and treated with dimethyl sulfate or methyl iodide. Removal of solvent and recrystallization from petroleum ether followed by sublimation gave colorless crystals of methyl manganese pentacarbonyl, m.p. 94.5-95°( uncorr.).

Fluorine as a ligand substituent in organometallic chemistry: A second chance and a second research career

“…Initial reports of the preparation of CH 3 Mn(CO) 5 by decarbonylation of the acyl precursor CH 3 COMn(CO) 5 were communicated by researchers at the Ethyl Corporation in 1957, in two pithy communications that fit on a single journal page [3,4]. These were followed quickly by analogous approaches to the preparation of CF 3 Mn(CO) 5 almost simultaneously by the group at Ethyl [5], the Stone group at Harvard [6], and by McClellan at DuPont [7], and to CF 3 Co(CO) 4 and other fluoroalkyl analogues by Hieber [8]. Formation of other perfluoroalkyl-metal compounds via oxidative addition reactions of R F -I to low-valent metal centers was pioneered by the Stone group [9,10].…”

“…Contributions to this area were reviewed 20 years ago [21], but a few examples are presented here for the purpose of perspective, and also to introduce some recent illustrative results from DFT calculations. For example, while COT, first reported by Willstä tter in 1911 [22], was shown to react with Fe(CO) 5 to give 1, in which the COT is bound as a 1,3-diene, and in which the Fe(CO) 3 unit undergoes a facile peripheral perambulation around the ring [23,24], OFCOT forms the previously mentioned complex 2 in which the coordination mode is quite different and the molecule is non-fluxional [25].…”

Carbon Dioxide Hydrogenation to Formate Catalyzed by a Bench-Stable, Non-Pincer-Type Mn(I) Alkylcarbonyl Complex

“…This step is accompanied by the release of 1-butanal, which under these conditions is hydrogenated to butanol as detected by 1 H NMR spectroscopy. This key activation step is a long-known textbook reaction, demonstrated for this class of complexes as early as in the 1950s and studied further by different authors in following years, and it makes this class of alkyl complexes attractive as bench-stable precursors to sensitive metal hydrido catalysts for hydrogenation reactions …”

Resurgence of Organomanganese(I) Chemistry. Bidentate Manganese(I) Phosphine–Phenol(ate) Complexes

“…For instance, the substitution chemistry of six-coordinate d 6 Mn­(CO) 5 X was instrumental in the discovery of the cis effect . Migratory insertions was first observed on the MeMn­(CO) 5 complex, and the first M–M bond in a molecular species was discovered with Mn 2 (CO) 10 . , …”