Chiral ligand (R)-N, N'-Bis(2-hydroxy-3,5-di- tert-butyl-aryl-methyl)-1, 1'-binaphthalene-2,2'-diamine derived from the reduction of Schiff base (R)-2,2'-bis (3,5-di-tert-butyl-2-hy-droxybenzylideneami...Chiral ligand (R)-N, N'-Bis(2-hydroxy-3,5-di- tert-butyl-aryl-methyl)-1, 1'-binaphthalene-2,2'-diamine derived from the reduction of Schiff base (R)-2,2'-bis (3,5-di-tert-butyl-2-hy-droxybenzylideneamino)-1, 1'-binaphthyl with LiAIH(4) is fairly effective in the asymmetric addition reaction of diethylzinc to aldehydes by which good yields (46%-94%) of the corresponding sec-alcohols can be obtained in moderate ee (51%-79%) with R configuration for a variety of aldehydes.展开更多
Optically active copolyesters based on axially dissymmetric 1,1'-binaphthalene-2,2'-diyl units have been preparedand characterized by specific rotation, ^(13)C-NMR and CD spectra. The results show that the rot...Optically active copolyesters based on axially dissymmetric 1,1'-binaphthalene-2,2'-diyl units have been preparedand characterized by specific rotation, ^(13)C-NMR and CD spectra. The results show that the rotation signs of tribasiccopolyesters or the mixture of corresponding homopolyesters obey a three dimensional quadrant pattern. The composition ofthe copolyesters was determined from ^(13)C-NMR spectra to be triad sequence distributions and corresponding with the ratioby feed.展开更多
Density functional theory (DFT) was applied to study the ground state geometries and isomerization processes of 1,1'-binaphthalene-8,8'-diol. Three isomers, denoted as ISO1, ISO2, and ISO3, were found, distinguish...Density functional theory (DFT) was applied to study the ground state geometries and isomerization processes of 1,1'-binaphthalene-8,8'-diol. Three isomers, denoted as ISO1, ISO2, and ISO3, were found, distinguished by different orientations of the OH groups, and each OH-orientational isomer has R- and S-enantiomer. The conformational stabilities of these isomers were investigated by tracking the energy change with respect to the ring-to-ring torsion. The inter-conversions between the three OH-orientational S-isomers were found to have quite low barriers owing to the nearly free rotation of OH groups around the O-C single bonds. The S-R enantiomerization of ISO1 and ISO2 can take place through the ring-ring torsion around the C1-C1/ single bond, either in the anti-rotation manner or in the syn-rotation manner. The barriers of the anti routes are lower than those of the corresponding syn routes by 87.95 and 75.04 kJ/mol. For the S-R enantiomerization of ISO3, only the anti route was found. The barriers for the anti route enantiomerizations of ISO1, ISO2, and ISO3 are 119.61, 120.43, and 121.59 kJ/mol, respectively. A parallel reaction mechanism via three anti enantiomerization routes was proposed for the racemization of 1,1'-binaphthalene-8,8'-diol.展开更多
Menthol reacts with phosphorus trichloride to afford menthyl phosphorodichloridite 2, which further reacts with racemic 1, 1-binaphthalene-2, 2-diol to give phosphite (+)-3 in the presence of triethylamine. (+)-3 can ...Menthol reacts with phosphorus trichloride to afford menthyl phosphorodichloridite 2, which further reacts with racemic 1, 1-binaphthalene-2, 2-diol to give phosphite (+)-3 in the presence of triethylamine. (+)-3 can be easily separated by fractional crystallization to form the crystal (+)-(S)-3 and the mother liquor (-)-(R)-3. Then both the crystal and the mother liquor are treated with AcOH-H2O to obtain enantiomeric pure (-)-(S)-1 and (+)-(R)-1 respectively, with enantiomeric excess up to 99.7%.展开更多
基金theMajorStateBasicResearchDevelopmentProgram (No .G2 0 0 0 0 480 0 7)andtheNationalNaturalScienceFoundationofChina (No .2 0 0 2 5 2 0 6 )
文摘Chiral ligand (R)-N, N'-Bis(2-hydroxy-3,5-di- tert-butyl-aryl-methyl)-1, 1'-binaphthalene-2,2'-diamine derived from the reduction of Schiff base (R)-2,2'-bis (3,5-di-tert-butyl-2-hy-droxybenzylideneamino)-1, 1'-binaphthyl with LiAIH(4) is fairly effective in the asymmetric addition reaction of diethylzinc to aldehydes by which good yields (46%-94%) of the corresponding sec-alcohols can be obtained in moderate ee (51%-79%) with R configuration for a variety of aldehydes.
基金This work was supported by the State Key Laboratory of Functional Polymer Materials for Adsorption and Separation, Nankai University.
文摘Optically active copolyesters based on axially dissymmetric 1,1'-binaphthalene-2,2'-diyl units have been preparedand characterized by specific rotation, ^(13)C-NMR and CD spectra. The results show that the rotation signs of tribasiccopolyesters or the mixture of corresponding homopolyesters obey a three dimensional quadrant pattern. The composition ofthe copolyesters was determined from ^(13)C-NMR spectra to be triad sequence distributions and corresponding with the ratioby feed.
文摘Density functional theory (DFT) was applied to study the ground state geometries and isomerization processes of 1,1'-binaphthalene-8,8'-diol. Three isomers, denoted as ISO1, ISO2, and ISO3, were found, distinguished by different orientations of the OH groups, and each OH-orientational isomer has R- and S-enantiomer. The conformational stabilities of these isomers were investigated by tracking the energy change with respect to the ring-to-ring torsion. The inter-conversions between the three OH-orientational S-isomers were found to have quite low barriers owing to the nearly free rotation of OH groups around the O-C single bonds. The S-R enantiomerization of ISO1 and ISO2 can take place through the ring-ring torsion around the C1-C1/ single bond, either in the anti-rotation manner or in the syn-rotation manner. The barriers of the anti routes are lower than those of the corresponding syn routes by 87.95 and 75.04 kJ/mol. For the S-R enantiomerization of ISO3, only the anti route was found. The barriers for the anti route enantiomerizations of ISO1, ISO2, and ISO3 are 119.61, 120.43, and 121.59 kJ/mol, respectively. A parallel reaction mechanism via three anti enantiomerization routes was proposed for the racemization of 1,1'-binaphthalene-8,8'-diol.
基金Financial Support by the National Natural Science Foundation of China (No.29872016) the Hong Kong Polytechnic University ASD Fund are gratefully acknowledged.
文摘Menthol reacts with phosphorus trichloride to afford menthyl phosphorodichloridite 2, which further reacts with racemic 1, 1-binaphthalene-2, 2-diol to give phosphite (+)-3 in the presence of triethylamine. (+)-3 can be easily separated by fractional crystallization to form the crystal (+)-(S)-3 and the mother liquor (-)-(R)-3. Then both the crystal and the mother liquor are treated with AcOH-H2O to obtain enantiomeric pure (-)-(S)-1 and (+)-(R)-1 respectively, with enantiomeric excess up to 99.7%.