A new method for the preparation of microcapsule-supported palladium catalyst was described.The highly monodisperse crosslinked polystyrene microcapsules containing phosphine ligand were synthesized by the self-assemb...A new method for the preparation of microcapsule-supported palladium catalyst was described.The highly monodisperse crosslinked polystyrene microcapsules containing phosphine ligand were synthesized by the self-assembling of phase separated polymer （SaPSeP） method using diphenyl（4-vinylphenyl） phosphine and divinylbenzene as a monomer and crosslinking agent,respectively, and 2,2＇-azobisisobutyronitrile（AIBN） as an initiator within the droplets of oil-in-water（O/W） emulsions,which were prepared by using the Shirasu Porous Glass（SPG） membrane emulsification technique.The prepared microcapsule-supported palladium catalyst exhibited high catalytic activity for Heck reaction and can be reused several times without loss of activity.展开更多
The reaction mechanism of OBrO with OH has been studied using the B3LYP/6-311+G(d,p) and the high-level electron-correlation CCSD(T)/6-311+G(d,p) at single-point. The results show that the title reaction could probabl...The reaction mechanism of OBrO with OH has been studied using the B3LYP/6-311+G(d,p) and the high-level electron-correlation CCSD(T)/6-311+G(d,p) at single-point. The results show that the title reaction could probably proceed by four possible schemes, generating HOBr+O2, HBr+O3, BrO+HO2 and HOBrO2 products, respec-tively. The main channel is the one to yield HOBr+O2. The whole reaction involves the formation of three-membered, four-membered and five-membered rings, followed by the complicated processes of association, H-shift, Br-shift and dissociation. All routes are exothermic.展开更多
基金the National Natural Science Foundation of China(No.20572010) for financial supportsupported by the program for Changjiang Scholars and Innovative Research Teams in Universities (No.IRT0711)
文摘A new method for the preparation of microcapsule-supported palladium catalyst was described.The highly monodisperse crosslinked polystyrene microcapsules containing phosphine ligand were synthesized by the self-assembling of phase separated polymer （SaPSeP） method using diphenyl（4-vinylphenyl） phosphine and divinylbenzene as a monomer and crosslinking agent,respectively, and 2,2＇-azobisisobutyronitrile（AIBN） as an initiator within the droplets of oil-in-water（O/W） emulsions,which were prepared by using the Shirasu Porous Glass（SPG） membrane emulsification technique.The prepared microcapsule-supported palladium catalyst exhibited high catalytic activity for Heck reaction and can be reused several times without loss of activity.
基金Project supported by Ministry of Education (the training project of elitist) Foundation ([2001] 3) and the Young Teacher Fund of Northeast Normal University (No. 111382).
文摘The reaction mechanism of OBrO with OH has been studied using the B3LYP/6-311+G(d,p) and the high-level electron-correlation CCSD(T)/6-311+G(d,p) at single-point. The results show that the title reaction could probably proceed by four possible schemes, generating HOBr+O2, HBr+O3, BrO+HO2 and HOBrO2 products, respec-tively. The main channel is the one to yield HOBr+O2. The whole reaction involves the formation of three-membered, four-membered and five-membered rings, followed by the complicated processes of association, H-shift, Br-shift and dissociation. All routes are exothermic.
