Ewin, Richard A.; MacLeod, Angus M.; Price, David A., Journal of the Chemical Society. Perkin transactions I, 1997, # 4, p. 401 - 415
作者:Ewin, Richard A.、MacLeod, Angus M.、Price, David A.、Simpkins, Nigel S.、Watt, Alan P.
DOI:——
日期:——
The asymmetric synthesis of phosphorus- and sulfur-containing tricarbonyl(η6-arene)chromium complexes using the chiral base approach
作者:Azhar Ariffin、Alexander J. Blake、Richard A. Ewin、Wan-Sheung Li、Nigel S. Simpkins
DOI:10.1039/a905610f
日期:——
transformation of tricarbonyl[η6-(diphenylphosphinoyl)benzene]chromium(0) 12 into the corresponding ortho-silylated complex in up to 86% ee. A tin derivative was prepared similarly and was then used to prepare other derivatives via reduction to the corresponding phosphine, followed by transmetallation–electrophilic quench. In the case of tricarbonyl(η6-1,3-dihydroisobenzothiophene)chromium(0) the chiral
A Synthetic and Mechanistic Investigation of the Chromium Tricarbonyl-Mediated Masamune–Bergman Cyclization. Direct Observation of a Ground-State Triplet<i>p</i>-Benzyne Biradical
作者:Kai E. O. Ylijoki、Séverine Lavy、Angelika Fretzen、E. Peter Kündig、Théo Berclaz、Gérald Bernardinelli、Céline Besnard
DOI:10.1021/om300427j
日期:2012.8.13
bond formation from an η6-enediyne complex is the lowest-energy path, forming a metal-bound p-benzyne biradical. NMR spectroscopy suggests that enediyne alkene coordination occurs in preference to alkyne coordination, forming a THF-stabilized olefinintermediate; subsequent alkyne coordination leads to cyclization. While biradical quenching occurs rapidly and primarily via the singlet biradical, the