Chiral diphenylperhydroindolinol silyl ether catalyzed domino oxa-Michael–aldol condensations for the asymmetric synthesis of benzopyrans
摘要:
Asymmetric domino oxa-Michael-aldol reactions between trans-cinnamaldehydes and salicylic aldehyde derivatives have been developed. Using (2S,3aS,7aS)-diphenylperhydro indolinol silyl ether 4i as the catalyst, most corresponding chiral benzopyrans can be obtained with excellent chemo- and enantioselectivities. (C) 2014 Elsevier Ltd. All rights reserved.
Enantioselective organocatalytic synthesis of the chiral chromenes by domino oxa-Michael-aldol reaction
作者:Shrikant S. Pendalwar、Avinash V. Chakrawar、Sudhakar R. Bhusare
DOI:10.1016/j.cclet.2017.09.058
日期:2018.6
found to be an efficient catalyst for the facile synthesis of substituted 2-aryl-2H-chromenes-3-carbaldehyde. We envisioned that the iminium interaction between chiral amino catalysts and α,β-unsaturated carbonyl group was beneficial along with thiourea group as hydrogen bond donor, heterocyclic amines as general base in the domino oxa-Michael-aldol reaction. This catalytic system provided the products
One-pot approach to chiral chromenesvia enantioselective organocatalytic domino oxa-Michael–aldol reaction
作者:Hao Li、Jian Wang、Timiyin E-Nunu、Liansuo Zu、Wei Jiang、Shaohua Wei、Wei Wang
DOI:10.1039/b611502k
日期:——
A highly enantioselective (S)-diphenylpyrrolinol triethylsilyl ether promoted tandem oxa-Michaelâaldol reaction of α,β-unsaturated aldehydes with salicylaldehydes has been developed; the method affords one-pot access to chiral and synthetically useful chromenes in high yields and high enantioselectivities from readily available compounds.
Chiral diphenylperhydroindolinol silyl ether catalyzed domino oxa-Michael–aldol condensations for the asymmetric synthesis of benzopyrans
作者:Ya-Hui Feng、Ren-Shi Luo、Lin Nie、Jiang Weng、Gui Lu
DOI:10.1016/j.tetasy.2014.02.016
日期:2014.4
Asymmetric domino oxa-Michael-aldol reactions between trans-cinnamaldehydes and salicylic aldehyde derivatives have been developed. Using (2S,3aS,7aS)-diphenylperhydro indolinol silyl ether 4i as the catalyst, most corresponding chiral benzopyrans can be obtained with excellent chemo- and enantioselectivities. (C) 2014 Elsevier Ltd. All rights reserved.
Catalytic Enantioselective Domino Oxa-Michael/Aldol Condensations: Asymmetric Synthesis of Benzopyran Derivatives
The first direct organocatalyticasymmetricdomino oxa-Michael/aldol condensation reaction is presented. The unprecedentedly simple, chiral, pyrrolidine-catalyzed asymmetricdominoreactions between salicylic aldehyde derivatives and alpha,beta-unsaturated aldehydes proceed with high chemo- and enantioselectivities to give the corresponding chromene-3-carbaldehyde derivatives in high yields and with