A series of carboxylated long chain polyethylene glycols(abbreviated as PEGCOOH) has been synthesized and used to support chloroplatinic acid.These supported catalysts were then tested for their efficiency in the hydr...A series of carboxylated long chain polyethylene glycols(abbreviated as PEGCOOH) has been synthesized and used to support chloroplatinic acid.These supported catalysts were then tested for their efficiency in the hydrosilylation of alkenes.The factors affecting their catalytic properties,e.g.relative molecular mass of polyethylene glycol,reaction temperature,platinum content,and type of alkenes,have been studied.It was found that the activity of the platinum catalyst decreased with increasing length of the polyethylene glycol chain,and increased with reaction temperature.Moreover,these catalysts could be reused several times without a noticeable decrease in activity or selectivity.The reaction pathway leading to excellent selectivity for the β-adduct of hydrosilylation of alkenes with triethoxysilane catalyzed by this catalysis system was discussed.展开更多
A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild rea...A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild reaction conditions.This reaction provides a facile and sustainable method for the synthesis of tricarboxylates by using CO_(2) as the carboxylic source.展开更多
基金Supported by the Educational Commission of Zhejiang Province of China (Y201017419)Zhejiang Province Program(2008C14041)
文摘A series of carboxylated long chain polyethylene glycols(abbreviated as PEGCOOH) has been synthesized and used to support chloroplatinic acid.These supported catalysts were then tested for their efficiency in the hydrosilylation of alkenes.The factors affecting their catalytic properties,e.g.relative molecular mass of polyethylene glycol,reaction temperature,platinum content,and type of alkenes,have been studied.It was found that the activity of the platinum catalyst decreased with increasing length of the polyethylene glycol chain,and increased with reaction temperature.Moreover,these catalysts could be reused several times without a noticeable decrease in activity or selectivity.The reaction pathway leading to excellent selectivity for the β-adduct of hydrosilylation of alkenes with triethoxysilane catalyzed by this catalysis system was discussed.
文摘A photoredox-catalyzed cascade carbon/carboxylation of activated alkenes with malonates acetals and CO_(2) has been achieved,leading to a range of functionalized 1,1,3-tricarboxylates in good efficiency under mild reaction conditions.This reaction provides a facile and sustainable method for the synthesis of tricarboxylates by using CO_(2) as the carboxylic source.
