of manganese as a mediator for allylations and pinacol couplings in aqueousmedia was investigated. The combination of manganese and copper is found to be a highly effective mediator for the allylation of aryl aldehydes in water. Such a combination is found to be more reactive than other previously reported metals in aqueousmedia. No reaction was observed with either manganese or copper alone as the
Application of coumarin dyes for organic photoredox catalysis
作者:Andrea Gualandi、Giacomo Rodeghiero、Emanuele Della Rocca、Francesco Bertoni、Marianna Marchini、Rossana Perciaccante、Thomas Paul Jansen、Paola Ceroni、Pier Giorgio Cozzi
DOI:10.1039/c8cc04048f
日期:——
Here we report the application of readily prepared and available coumarin dyes for photoredoxcatalysis, which are able to mimic powerful reductant [Ir(III)] complexes. Coumarin derivatives 9 and 10 were employed as photoreductants in pinacol coupling and in other reactions, in the presence of Et3N as a sacrificial reducing agent. As the electronic, photophysical, and steric properties of coumarins
high reduction potential of carbonyl compounds and imines. In the context of photoredox catalysis, tertiary amines are commonly employed as sacrificial co‐reducing agents. Herein, an additional role of the amine is proposed, in which it is essential for the organocatalytic substrate activation. The combination of photoredox catalysis and carbonyl/imine activation enables the reductivecoupling of aldehydes
A highly stereoselective pinacolization of aromatic and α, β-unsaturated aldehydes.dta mediated by titanium(III)-magnesium(II) complex
作者:Yuichi Handa、Junji Inanaga
DOI:10.1016/s0040-4039(00)96822-9
日期:1987.1
Reduction of Cp2TiCl2 withsec-BuMgCl in THF gave a greenish deep brown solution which has been found to promote the reductive homocoupling of aromatic and α, β-unsaturated aldehydes to yield symmetrical 1, 2-diols with highthreo-selectivity.