Dual catalysis: combining photoredox and Lewis base catalysis for direct Mannich reactions
作者:Magnus Rueping、Carlos Vila、René M. Koenigs、Konstantin Poscharny、David C. Fabry
DOI:10.1039/c0cc04539j
日期:——
A dual catalytic system combining photoredox and Lewis base catalysis has been developed. By the appropriate choice of light source and catalyst, the photoredox cycle can be optimally modulated to match the base catalyzed reaction cycle to provide the corresponding products under mild reaction conditions.
An anthraquinone-containing polymericphotosensitizer (AQ-PHEMA) can catalyze the cross-dehydrogenative-coupling of N-aryl tetrahydroisoquinolines with several nucleophiles (nitromethane, 1-methyl-2-alkyl ketone and dialkyl (aryl) phosphine oxide) efficiently by visible light to afford a series of 1-substituted-2-aryl-1,2,3,4-tetrahydroisoquinolines in good to excellent yields with nice substrate tolerance