Bifunctional Phosphine-Catalyzed Domino Reaction: Highly Stereoselective Synthesis of cis-2,3-Dihydrobenzofurans from Salicyl N-Thiophosphinyl Imines and Allenes
摘要:
A new bifunctional phosphine catalyst, (2'-hydroxy-biphenyl-2-yl)-diethylphosphane (LBBA-1), was developed for the highly stereoselective synthesis of cis-2,3-dihydrobenzofurans via an aza-Morita-Baylis-Hillman/umpolung addition domino reaction of salicyl N-thiophosphinyl Imines with electron-deficient allenes. Dual activation of both nucleophile and electrophile by the bifunctional catalyst accounts for the observed high reactivity and stereoselectivity.
Domino Reaction for the Chemo- and Stereoselective Synthesis of <i>trans</i>-2,3-Dihydrobenzofurans from <i>N</i>-Thiophosphinyl Imines and Sulfur Ylides
A novel domino annulation between sulfur ylides and salicyl N-thiophosphinyl imines was developed. The method allows the synthesis of a highly substituted trans-2,3-dihydrobenzofuran skeleton with high yield and excellent chemo- and stereoselectivity.
Synthesis of Functionalized Chromans by P<sup><i>n</i></sup>Bu<sub>3</sub>-Catalyzed Reactions of Salicylaldimines and Salicylaldehydes with Allenic Ester
作者:Yin-Wei Sun、Xiao-Yang Guan、Min Shi
DOI:10.1021/ol102461c
日期:2010.12.17
P(n)Bu3-catalyzed cyclization reactions of salicylaldimines and salicylaldehydes with ethyl 2,3-butadienoate gave the corresponding functionalized chromans in moderate to good yields in THF under mild conditions. The new reaction provides a new method for the synthesis of biologically active chroman products.
PPh<sub>3</sub>-Catalyzed Domino Reaction: A Facile Method for the Synthesis of Chroman Derivatives
A novel domino reaction catalyzed by triphenylphosphine was developed for synthesis of the highly functionalized chroman derivatives. The first example that the gamma-CH3 of allenoate undergoes cyclization to form chroman derivates was reported.