Enantioselective Desymmetrization of Curcumins with 3‐Olefinic Oxindoles for the Synthesis of Spirocyclohexanoneoxindoles
作者:Chenikkayala Siva Sankara、Shweta Bhagat、Ajeet Chandra、Irishi N. N. Namboothiri
DOI:10.1002/ejoc.202300069
日期:——
Spiro-oxindoles containing three contiguous chiral centers were synthesized with excellent diastereo- and enantioselectivities via cascade double Michael reactions of curcumins with 3-alkylideneoxindole carboxylates. The selectivities are supported by transitions state energy calculations at B3LYP//6-31g(d) level of DFT.
Asymmetric synthesis of multicyclic spiro-1,3-indandiones via a cascade Michael/Michael reaction of curcumins and 2-arylidene-1,3-indandiones
作者:Nian-hua Luo、Xiang Sun、Wen-tao Wei、Xue-jing Zhang、Ming Yan
DOI:10.1016/j.tetasy.2013.02.014
日期:2013.4
An organocatalytic cascade Michael/Michael reaction between curcumins and 2-arylidene-1,3-indandiones has been studied. Prolinol, chiral thiourea-tertiary amines, and cinchona alkaloids were evaluated as catalysts. Quinine was identified as the best catalyst for the transformation. Multicyclic spiro-1,3-indandiones were prepared in moderate to excellent yields, diastereoselectivities, and enantioselectivities. (c) 2013 Elsevier Ltd. All rights reserved.