The catalytic radical-initiated asymmetric 1,2-aminosilylation of alkene with a hydrosilane under Cu(I)/CPA cooperative catalysis has been developed.This method features the use of hydrosilane as the reductive radical...The catalytic radical-initiated asymmetric 1,2-aminosilylation of alkene with a hydrosilane under Cu(I)/CPA cooperative catalysis has been developed.This method features the use of hydrosilane as the reductive radical precursor,enabling efficient access to skeletally diverse silicon-containing azaheterocycles including pyrrolidine,indoline and isoindoline bearing anα-tertiary stereocenter with high enantioselectivity.The key to the success includes the use of Cu(I)/CPA cooperative catalyst system and theβ-silicon effect of the silyl group to stabilize the in situ generated carbocation intermediate.展开更多
Under hydrothermal conditions,homochiral ligand(4aR,8aR)-2,3-di(thiophen-2-yl)-decahydroquinoxaline (DTDCQ) reacted with CuBr to give 1D helical chain complexes[(DTHHQ)CuBr]_n(1).Single crystal X-ray determination sho...Under hydrothermal conditions,homochiral ligand(4aR,8aR)-2,3-di(thiophen-2-yl)-decahydroquinoxaline (DTDCQ) reacted with CuBr to give 1D helical chain complexes[(DTHHQ)CuBr]_n(1).Single crystal X-ray determination shows that compound 1 crystallize in chiral space groups P2_12_12_1 and the experimental result indicated that 1 has SHG(second harmonic generation) active with approximate responses 0.4 times that of urea,Fluorescent analysis showed it exhibits one intense emission band at 377 nm when the exciting radiation was set at 340 nm. Dielectric constant of compound 1 were measured at different frequencies at room temperature.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
基金supported by the National Natural Science Foundation of China(21722203,21831002,21801116,21572096)Shenzhen Special Funds for the Development of Biomedicine,Internet,New Energy,and New Material Industries(JCYJ20170412152435366,JCYJ20170307105638498,JCYJ20180302180235837)+1 种基金Guangdong Natural Science Foundation(2018A030310083)Shenzhen Nobel Prize Scientists Laboratory Project(C17783101)
文摘The catalytic radical-initiated asymmetric 1,2-aminosilylation of alkene with a hydrosilane under Cu(I)/CPA cooperative catalysis has been developed.This method features the use of hydrosilane as the reductive radical precursor,enabling efficient access to skeletally diverse silicon-containing azaheterocycles including pyrrolidine,indoline and isoindoline bearing anα-tertiary stereocenter with high enantioselectivity.The key to the success includes the use of Cu(I)/CPA cooperative catalyst system and theβ-silicon effect of the silyl group to stabilize the in situ generated carbocation intermediate.
文摘Under hydrothermal conditions,homochiral ligand(4aR,8aR)-2,3-di(thiophen-2-yl)-decahydroquinoxaline (DTDCQ) reacted with CuBr to give 1D helical chain complexes[(DTHHQ)CuBr]_n(1).Single crystal X-ray determination shows that compound 1 crystallize in chiral space groups P2_12_12_1 and the experimental result indicated that 1 has SHG(second harmonic generation) active with approximate responses 0.4 times that of urea,Fluorescent analysis showed it exhibits one intense emission band at 377 nm when the exciting radiation was set at 340 nm. Dielectric constant of compound 1 were measured at different frequencies at room temperature.
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.
