N-Heterocyclic Carbene (NHC)-Catalyzed Highly Diastereo- and Enantioselective Oxo-Diels–Alder Reactions for Synthesis of Fused Pyrano[2,3-b]indoles
摘要:
A chiral N-heterocyclic carbene (NHC)-catalyzed Diels-Alder reaction of 2-oxoindolin-3-ylidenes and alpha-chloroaldehydes was developed for the synthesis of fused pyrano[2,3-b]indoles in good to excellent yields (up to 99%) with high cis-diastereoselectivities (>99:1 dr) and enantioselectivities (up to >99% ee).
Phosphine-Catalyzed Rauhut-Currier Domino Reaction: A Facile Strategy for the Construction of Carbocyclic Spirooxindoles Skeletons
作者:Chongchong Hu、Qinglong Zhang、You Huang
DOI:10.1002/asia.201300650
日期:2013.9
Push‐over: A novel dominoreaction of activated conjugated dienes and methyleneindolinones incorporates a phosphine‐catalyzed intermolecular Rauhut–Currier to form two CC bonds and a quaternary carbon center. This method can be used to synthesize spirocyclopenteneoxindoles skeletons, which are potential building blocks for biologically active compounds.
Construction of dispirocyclohexanes via amine-catalyzed [2 + 2 + 2] annulations of Morita–Baylis–Hillman acetates with exocyclic alkenes
作者:Rongshun Chen、Silong Xu、Xia Fan、Hanyuan Li、Yuhai Tang、Zhengjie He
DOI:10.1039/c4ob01927j
日期:——
Amine-catalyzed [2 + 2 + 2] annulations of one molecule of Morita–Baylis–Hillman (MBH) acetates 1 with two molecules of 2-(arylmethylidene)indane-1,3-diones 2 or methyleneindolinones 4 have been developed under very mild conditions, which produce multistereogenic dispirocyclohexanes 3 and 5, respectively, in moderate to excellent yields and good diastereoselectivity. This amine-catalyzed annulation constitutes