Optically Active Transition-Metal Complexes. 9.1 A General Stereoselective Route to -Chiral (R)-Tricarbonyl(![]()
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- 作者：Ulli Englert ; Roland Haerter ; Daniela Vasen ; Albrecht Salzer ; Eva B. Eggeling ; and Dieter Vogt
- 刊名：Organometallics
- 出版年：1999
- 出版时间：October 11, 1999
- 年：1999
- 卷：18
- 期：21
- 页码：4390 - 4398
- 全文大小：130K
- 年卷期：v.18,no.21(October 11, 1999)
- ISSN：1520-6041
文摘
Treatment of (R)-[{
-(dimethylamino)ethyl}-
6-benzene]Cr(CO)3 with esters of chloroformicacid leads to stereoselective substitution of the dimethylamino group for a chloro substituent.The reaction can be extended to systems in which the chromium arene complex, aftermetalation, is diastereoselectively substituted in the ortho position with carbon and siliconelectrophiles to generate planar chirality. The chloro group in turn can be replacedstereoselectively for various phosphorus, nitrogen, and oxygen nucleophiles. Both substitutionreactions in the benzylic position proceed via retention of configuration. The addition ofcyanide is not stereospecific. The phosphine derivatives are efficient catalysts for theenantioselective hydrovinylation of styrene to 3-phenyl-1-butene. X-ray crystal structuresestablish the absolute configuration of (R)-[(-chloroethyl)6-benzene]Cr(CO)3, (R)-[{-(diphenylphosphanyl)ethyl}-6-benzene]Cr(CO)3, and (pS,S)-[1-(-cyanoethyl)-2-methyl-6-benzene]Cr(CO)3.
-(dimethylamino)ethyl}-6-benzene]Cr(CO)3 with esters of chloroformicacid leads to stereoselective substitution of the dimethylamino group for a chloro substituent.The reaction can be extended to systems in which the chromium arene complex, aftermetalation, is diastereoselectively substituted in the ortho position with carbon and siliconelectrophiles to generate planar chirality. The chloro group in turn can be replacedstereoselectively for various phosphorus, nitrogen, and oxygen nucleophiles. Both substitutionreactions in the benzylic position proceed via retention of configuration. The addition ofcyanide is not stereospecific. The phosphine derivatives are efficient catalysts for theenantioselective hydrovinylation of styrene to 3-phenyl-1-butene. X-ray crystal structuresestablish the absolute configuration of (R)-[(-chloroethyl)6-benzene]Cr(CO)3, (R)-[{-(diphenylphosphanyl)ethyl}-6-benzene]Cr(CO)3, and (pS,S)-[1-(-cyanoethyl)-2-methyl-6-benzene]Cr(CO)3.