Synthesis and Reactions of 1-Acetyl-2-benzylidene-3-oxo-2,3-dihydroindoles
作者:A. Buzas、J. Y. Merour
DOI:10.1055/s-1989-27289
日期:——
1-Acetyl-3-oxo-2,3-dihydroindoles were reacted with substituted benzaldehydes affording 1-acetyl-2-arylmethylene-3-oxo-2,3-dihydroindoles which were selectively reduced by hydrogen; then a Horner-Emmons reaction gave the precursors of 2-substituted tryptamines. Nitromethane was added to 1-acetyl-2-arylmethylene-3-oxo-2,3-dihydroindoles giving Michael addition products.
carbon center at the C2 position of indole has long been an elusive problem in organic synthesis. Herein, by employing a rationally designed hydrogen‐bonding network activation strategy, for the first time, 2,2′‐pyrrolidinyl‐spirooxindole, which is a valuable and prevalent indole alkaloid scaffold, was directly obtained through a catalyticasymmetric [3+2] cycloaddition reaction with high yields and excellent
A series of enantiomerically enriched 2-spirocyclopentyl-indolin-3-ones were obtained through a phosphine-catalyzed [3+2] cycloaddition between aza-aurones and allenoates.
BUZAS, A.;MEROUR, J. Y., SYNTHESIS (BRD),(1989) N, C. 458-461
作者:BUZAS, A.、MEROUR, J. Y.
DOI:——
日期:——
N-Heterocyclic Carbene Catalyzed Formal [3+2] Annulation Reaction of Enals: An Efficient Enantioselective Access to Spiro-Heterocycles
作者:Chang Guo、Michael Schedler、Constantin G. Daniliuc、Frank Glorius
DOI:10.1002/anie.201405381
日期:2014.9.15
A highly enantioselective N‐heterocyclic carbene (NHC) catalyzed formal [3+2] annulation of α,β‐unsaturated aldehydes with azaaurones or aurone generating spiro‐heterocycles has been developed. The protocol represents a unique NHC‐activation‐based approach to access spiro‐heterocyclic derivatives bearing a quaternary stereogenic center with high optical purity (up to 95 % ee).