Asymmetric Michael reactions on polymeric support: Auxiliary immobilization and stereoselective construction of quaternary stereocenters

B Kreidler, A Baro, J Christoffers

文献索引：Kreidler, Burkard; Baro, Angelika; Christoffers, Jens European Journal of Organic Chemistry, 2005 , # 24 p. 5339 - 5348

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被引用次数: 5

摘要

Abstract Several strategies for the immobilization of a L-valine-derived auxiliary on a Merrifield resin and on poly (ethylene glycol) are reported. The latter is shown to work excellently in asymmetric copper (II)-catalyzed Michael reactions of cyclic β-oxo esters 2 with methyl vinyl ketone (4), yielding the corresponding addition products 5 with quaternary stereocenter in selectivities of 97–99% ee. The PEG-supported auxiliary 1d can be ...