DIRHODIUM(II) TETRAKIS[N,N-DIMETHYL-2-PYRROLIDONE-5(S)-CARBOXAMIDE] - STRUCTURAL EFFECTS ON ENANTIOSELECTION IN METAL CARBENE TRANSFORMATIONS

被引：19

作者：

DOYLE, MP ^{[1
]}

WINCHESTER, WR ^{[1
]}

SIMONSEN, SH ^{[1
]}

GHOSH, R ^{[1
]}

机构：

[1] UNIV TEXAS,DEPT CHEM & BIOCHEM,AUSTIN,TX 78712

来源：

INORGANICA CHIMICA ACTA | 1994年 / 220卷 / 1-2期

基金：

美国国家科学基金会;

关键词：

CRYSTAL STRUCTURES; ENANTIOSELECTIVITY; CYCLOPROPANATION; RHODIUM CARBOXAMIDATE COMPLEXES; CARBENE COMPLEXES; DINUCLEAR COMPLEXES; CARBON HYDROGEN INSERTION;

D O I：

10.1016/0020-1693(94)03872-4

中图分类号：

O61 [无机化学];

学科分类号：

070301 ; 081704 ;

摘要：

The preparation and structural characterization of dirhodium(II) tetrakis[N,N-dimethyl-2-pyrrolidone-5(S)-carboxamide], Rh2(5S-DMAP)4, a new sterically-demanding catalyst for enantioselective metal carbene transformations, is described. The pyrrolidone ligands are arrayed around the dirhodium(II) core with two oxygen and two nitrogen donor atoms, each oriented cis, bound to each octahedral rhodium. The crystal structure of this compound has been determined to be that of Rh2(5S-DMAP)4(CH3CN)2.CH3CN.6H2O: space group P2(1)2(1)2, with cell constants a = 12.685(4), b = 15.050(3), c = 24.035(4) angstrom; v = 4588.5(1.9) angstrom3, Z = 4, R = 0.0316, Rh-Rh distance = 2.4538(5) angstrom. Decreased activity for diazodecomposition catalyzed by Rh2(5S-DMAP)4 is observed, and enantiocontrol for cyclopropanation and carbon-hydrogen insertion is lower than expected by analogy to the corresponding dirhodium(II) tetrakis[methyl 2-pyrrolidone-5(S)-carboxylate], Rh2(5S-MEPY)4. Electronic stabilization of the intermediate metal carbene is absent in reactions catalyzed by Rh2(5S-DMAP)4.

引用

页码：193 / 199

页数：7

共 23 条

[1]

ANGREV RB, 1956, J ORG CHEM, V21, P1540

[2] CRYSTALLOGRAPHIC STUDY AND LIGAND SUBSTITUTION-REACTIONS OF DIRHODIUM(II) TRIS(TRITOLYLBENZOATE) AND TETRAKIS(TRITOLYLBENZOATE) [J].