Direct Experimental Evidence for the Epimerization of Diastereoisomers in the Enantioselective Organocatalyzed Michael Addition of Acetoacetates to Nitroolefins

被引：10

作者：

Manzano, Ruben

Andres, Jose M.

Pedrosa, Rafael ^{[1
]}

机构：

[1] Univ Valladolid, Fac Ciencias, Inst CINQUIMA, E-47011 Valladolid, Spain

来源：

SYNLETT | 2011年 / 15期

关键词：

asymmetric synthesis; epimerization; Michael addition; organocatalysis; thioureas; CONJUGATE ADDITION; 1,3-DICARBONYL COMPOUNDS; BIFUNCTIONAL ORGANOCATALYSTS; TERTIARY STEREOCENTERS; THIOUREA DERIVATIVES; ADJACENT QUATERNARY; ASYMMETRIC ADDITION; NITROALKENES; KETONES; CYCLOHEXANONE;

D O I：

10.1055/s-0030-1261139

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The evolution of the addition of acetoacetates to nitrostyrene catalyzed by a bifunctional thiourea has been followed by F-19 NMR. The results show for the first time that the diastereoselectivity varies along the reaction time and that both the major and minor diastereoisomers epimerize in the presence of the catalyst.

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收藏

页码：2203 / 2205

页数：3

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