16030

Enantioselective Conjugate Addition to a,B-Unsaturated Esters and Amides Mediated by Lithium Perchlorate

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An efficient method for the cnantiosclcciivc lA -conjugate addition of arnines to A,B-Unsaturated esters containing an inexpensive chiral auxiliary. such as (S)-2-methyl- I-butanol and fcnchyl alco hol. in solvent-free condi tions mediated by solid lithium perchlorate is reported. Over 12 examples of thc products are generated in exce llent yields. accomp anied by moderate cnantiosc lcctivity . The concentrated solution of LiCI0 4 in a diethy l ether system works well for the cnantioselcctive lA-addition of organo lithium compounds to A,B-unsatura te d arnidcs without any side reactions

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