Optically Active Transition-Metal Complexes. 10.<sup>1</sup> Bifunctional Arene−Chromium−Tricarbonyl Complexes Derived from (<i>R</i>)-Phenylethanamine: Easily Accessible Planar-Chiral Diphosphines and Their Application in Enantioselective Hydrogenation, Hydroamination, and Allylic Sulfonation
作者:Daniela Vasen、A. Salzer、Frank Gerhards、Hans-Joachim Gais、Rainer Stürmer、Nikolaus H. Bieler、Antonio Togni
DOI:10.1021/om9907674
日期:2000.2.1
introduced into the α-position to generate bifunctional chelating ligands. The addition of cyanide is not fully diastereospecific. The diphosphines, structurally similar to the well-known “Josiphos”-ferrocenes, are good catalysts for rhodium-catalyzed enantioselective hydrogenation, iridium-catalyzed hydroamination, and palladium-catalyzed allylic sulfonation.
Investigations into the hydrogenation of diolefins and prochiral olefins employing the “Daniphos”-type ligandsDedicated to the memory of Professor Noel McAuliffe.
Their catalytic performance has been assessed by carrying out hydrogenations of dienes and prochiral olefins, taking the Josiphos ligand as a reference system for comparison. Interesting influences of the substitution patterns and solvents were found. Reaction rates of the hydrogenations of diolefins were also found to be strongly dependent on the respective substituents.
Optically Active Transition-Metal Complexes. 9.<sup>1</sup> A General Stereoselective Route to α-Chiral (<i>R</i>)-Tricarbonyl(η<sup>6</sup>-ethylbenzene)chromium Complexes. Novel Organometallic Phosphine Catalysts for the Asymmetric Hydrovinylation Reaction
作者:Ulli Englert、Roland Haerter、Daniela Vasen、Albrecht Salzer、Eva B. Eggeling、Dieter Vogt
DOI:10.1021/om990386q
日期:1999.10.1
nucleophiles. Both substitution reactions in the benzylic position proceed via retention of configuration. The addition of cyanide is not stereospecific. The phosphine derivatives are efficient catalysts for the enantioselective hydrovinylation of styrene to 3-phenyl-1-butene. X-ray crystal structures establish the absolute configuration of (R)-[(α-chloroethyl)η6-benzene]Cr(CO)3, (R)-[α-(diphenylphosphanyl