Chiral Ligand-Controlled Asymmetric Conjugate Addition of .ALPHA.-Trimethylsilanylacetate to Acyclic and Cyclic Enones
作者:Mayu Iguchi、Hirohisa Doi、Seiji Hata、Kiyoshi Tomioka
DOI:10.1248/cpb.52.125
日期:——
The reaction of lithium ester enolate with enones provides a challenge for chemoselectivity, that is, discrimination between a conjugate addition and a 1,2-addition. Asymmetric conjugate addition of a lithium enolate of alpha-trimethylsilanylacetate to acyclic and cyclic alpha,beta-unsaturated ketones was mediated by an external chiral ligand to give the corresponding 1,4-adducts in good enantioselectivity
烯醇锂酯与烯酮的反应为化学选择性提出了挑战,即区分缀合物加成和1,2-加成。外手性配体介导α-三甲基硅烷基乙酸乙烯酯的烯醇锂向无环和环状α,β-不饱和酮的不对称共轭加成,从而以74%的良好对映选择性和良好的化学选择性得到相应的1,4-加合物。