PPh3-Catalyzed Domino Reaction: A Facile Method for the Synthesis of Chroman Derivatives
摘要:
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.
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.
P(<i>n</i>-Bu)<sub>3</sub>Catalyzed Reactions of Salicyl<i>N</i>-Thiophosphinyl Imines with Allenylphosphonates: Synthesis of Phosphono-Chromans
作者:R. Rama Suresh、R. N. Prasad Tulichala、Ramesh Kotikalapudi、K. C. Kumara Swamy
DOI:10.1002/jhet.2071
日期:2014.5
A phosphine [P(n‐Bu)3]‐catalyzed reaction for the synthesis of phosphono‐chromans from allenylphosphonates and salicyl N‐thiophosphinyl imines has been described and compared with reactions for phosphorus‐free allenes. The products are (β,γ)‐cyclized and are obtained in good yields (57–83%). A key product is characterized by X‐ray crystallography.
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.