spectrometry show that reaction of I with excess hydrogen peroxide leads to fast formation of a diperoxo species, [TBA](4)[gamma-SiW(10)O(32)(O(2))(2)] (II), with retention of a gamma-Keggin type structure. Whereas the isolated compoundII is inactive for stoichiometric epoxidation of cyclooctene, epoxidation with II does proceed in the presence of hydrogen peroxide. The reaction of II with hydrogen peroxide
A divacant, lacunary, Keggin-type silicotungstate, [gamma-SiW10O34(H2O)(2)](4-), exhibits high catalytic performance for the epoxidation of various nonconjugated dienes using hydrogen peroxide under mild conditions, high regioselectivity to the more accessible double bonds, and high efficiency of hydrogen peroxide utilization. The high regioselectivity for the [gamma-SiW10O34(H2O)(2)](4-)-catalyzed epoxidation would be caused by the steric hindrance of the active site. (C) 2004 Elsevier Inc. All rights reserved.
Titanium-Catalyzed Asymmetric Epoxidation of Non-Activated Olefins with Hydrogen Peroxide
作者:Yuji Sawada、Kazuhiro Matsumoto、Tsutomu Katsuki
DOI:10.1002/anie.200700949
日期:2007.6.11
Atom-economical cobalt-catalysed regioselective coupling of epoxides and aziridines with alkenes
作者:Gabriele Prina Cerai、Bill Morandi
DOI:10.1039/c6cc04410g
日期:——
An atom-economical cobalt-catalysed regioselective coupling of epoxides and aziridines with alkenes is reported.