A phosphite ligand modified heterogeneous catalyst was developed for the hydroformylation of internal olefins to linear aldehydes, which showed a high activity and high regioselectivity and could be separated easily b...A phosphite ligand modified heterogeneous catalyst was developed for the hydroformylation of internal olefins to linear aldehydes, which showed a high activity and high regioselectivity and could be separated easily by filtration after reaction in an autoclave. Three nanoporous silica sieves were used to investigate the influence of pore structure and shape selective performance of support on the regioselectivity to the linear products.展开更多
A series of novel chiral diphosphite ligands have been synthesized from（1R,2R）-trans-1,2-cyclohexanediol,（1S,2S）-trans-1,2-cyclohexanediol, racemic trans-1,2-cyclohexanediol and chlorophosphoric acid diary ester, ...A series of novel chiral diphosphite ligands have been synthesized from（1R,2R）-trans-1,2-cyclohexanediol,（1S,2S）-trans-1,2-cyclohexanediol, racemic trans-1,2-cyclohexanediol and chlorophosphoric acid diary ester, and were successfully employed in the Cu-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to cyclohexenone with up to 99% ee. It was found that ligand 1,2-bis[（R）-1,10-binaphthyl-2,2＇-diyl]phosphitecyclohexanediol 6a derived from racemic diol skeleton can show similar catalytic performance compared with ligand（1R,2R）-bis[（R）-1,1＇-binaphthyl-2,2＇-diyl]phosphitecyclohexanediol 6a＇ derived from enantiopure starting material. A significant dependence of stereoselectivity on the type of enone and the ring size of the cyclic enone was observed. Moreover, the configuration of the products was mainly determined by the configuration of the binaphthyl moieties of diphosphite ligands in the 1,4-addition of cyclic enones.展开更多
Five novel tropos （3R,4R）- and/or （3S,4S）-N-benzyltartarimide-derived biphenylphosphite ligands were synthesized and applied in the Cu-catalyzed asymmetric conjugate addition of diethylzinc to cyclic enones with u...Five novel tropos （3R,4R）- and/or （3S,4S）-N-benzyltartarimide-derived biphenylphosphite ligands were synthesized and applied in the Cu-catalyzed asymmetric conjugate addition of diethylzinc to cyclic enones with up to 75% e.e. Compared with the reported ligand 1-N-benzylpyrrolidine-3,4-bis[（R）-1,1＇-binaphthyl-2,2＇-diyl]phosphite- L-tartaric acid, the issue that L-（＋）-tartaric acid backbone and （R）-binaphthyl showed strong matched/mismatched character was solved with these tropos ligands. It was found that the enantioselectivity was mainly controlled by the absolute configuration of N-benzyltartarimide backbone, and both enantiomers of the addition products can be obtained by simply changing the configuration of N-benzyltartarimide substituent.展开更多
基金Supported by the Ministry of Science and Technology of China(No.2009CB623503)
文摘A phosphite ligand modified heterogeneous catalyst was developed for the hydroformylation of internal olefins to linear aldehydes, which showed a high activity and high regioselectivity and could be separated easily by filtration after reaction in an autoclave. Three nanoporous silica sieves were used to investigate the influence of pore structure and shape selective performance of support on the regioselectivity to the linear products.
基金the National Natural Science Foundation of China (Nos. 20773147, 21073211, and 21174155)
文摘A series of novel chiral diphosphite ligands have been synthesized from（1R,2R）-trans-1,2-cyclohexanediol,（1S,2S）-trans-1,2-cyclohexanediol, racemic trans-1,2-cyclohexanediol and chlorophosphoric acid diary ester, and were successfully employed in the Cu-catalyzed asymmetric 1,4-conjugate addition of diethylzinc to cyclohexenone with up to 99% ee. It was found that ligand 1,2-bis[（R）-1,10-binaphthyl-2,2＇-diyl]phosphitecyclohexanediol 6a derived from racemic diol skeleton can show similar catalytic performance compared with ligand（1R,2R）-bis[（R）-1,1＇-binaphthyl-2,2＇-diyl]phosphitecyclohexanediol 6a＇ derived from enantiopure starting material. A significant dependence of stereoselectivity on the type of enone and the ring size of the cyclic enone was observed. Moreover, the configuration of the products was mainly determined by the configuration of the binaphthyl moieties of diphosphite ligands in the 1,4-addition of cyclic enones.
基金Supported by the National Natural Science Foundation of China （Nos.20773147, 21073211, 21174133）.
文摘Five novel tropos （3R,4R）- and/or （3S,4S）-N-benzyltartarimide-derived biphenylphosphite ligands were synthesized and applied in the Cu-catalyzed asymmetric conjugate addition of diethylzinc to cyclic enones with up to 75% e.e. Compared with the reported ligand 1-N-benzylpyrrolidine-3,4-bis[（R）-1,1＇-binaphthyl-2,2＇-diyl]phosphite- L-tartaric acid, the issue that L-（＋）-tartaric acid backbone and （R）-binaphthyl showed strong matched/mismatched character was solved with these tropos ligands. It was found that the enantioselectivity was mainly controlled by the absolute configuration of N-benzyltartarimide backbone, and both enantiomers of the addition products can be obtained by simply changing the configuration of N-benzyltartarimide substituent.
