Both impurity- and magnetic-field-induced quasiparticle states in chiral p-wave superconductors are investigated theoretically by solving the Bogoliubov-de Gennes equations self-consistently. At the strong scattering ...Both impurity- and magnetic-field-induced quasiparticle states in chiral p-wave superconductors are investigated theoretically by solving the Bogoliubov-de Gennes equations self-consistently. At the strong scattering limit, we find that a universal state bound to the impurity can be induced for both a single nonmagnetic impurity and a single magnetic impurity. Furthermore, we find that different chiral order parameters and the corresponding supercurrents have uniform distributions around linear impurities. Calculations of the local density of states in the presence of an external magnetic field show that the intensity peak of the zero-energy Majorana mode in the vortex core can be enhanced dramatically by tuning the strength of the external magnetic field or pairing interaction.展开更多
To investigate the recovery of amino alcohols as chiral auxiliaries, optically active p-benzyloxyphenylglycinol and its corresponding oxazolidine of 1-naphthylcarboxaldehyde were prepared. Grignard additions to the ox...To investigate the recovery of amino alcohols as chiral auxiliaries, optically active p-benzyloxyphenylglycinol and its corresponding oxazolidine of 1-naphthylcarboxaldehyde were prepared. Grignard additions to the oxazolidine followed by electrophilic quench and acidic hydrolysis afforded an aldehyde(compound 8)(later it was reduced to an alcohol, compound 9) in an excellent enantiomeric excess and a good recovery of the chiral amino alcohol. This research provides a model study of chiral amino alcohols in solid phase asymmetric synthesis.展开更多
An improved procedure for the preparation of China, BAD(P)H model. (S_s)- 1 -benzyl-3- (p-tolylsulfinyl)-1.4-dihydropyridine with satisfactary chemical yield and excellent enantiopurity is reported.
本文利用低温扫描隧道显微镜(low temperature scanning tunneling microscopy,LT-STM)研究了四联苯分子在半金属Bi(111)表面上的超分子手性及其自组装结构。在极低的覆盖度下,四联苯分子形成纳米尺度的分子团簇,团簇中的分子有平躺和...本文利用低温扫描隧道显微镜(low temperature scanning tunneling microscopy,LT-STM)研究了四联苯分子在半金属Bi(111)表面上的超分子手性及其自组装结构。在极低的覆盖度下,四联苯分子形成纳米尺度的分子团簇,团簇中的分子有平躺和侧躺的取向。随着覆盖度的增加,四联苯分子形成多畴的自组装单层结构。自组装单层的基本结构单元是由两个平躺分子和一个侧躺分子构成的三聚体。高分辩的STM图表明,平躺的四联苯分子表现出结构对称性,而侧躺的四联苯分子表现为四个之字形的突起,表明四个苯环之间发生了扭曲,使得三聚体团簇具有超分子手性。有趣的是,在畴区内部相邻两个三聚体的手性相反;在畴界两侧两个三聚体的手性相同,表明同手性的三聚体之间存在空间位阻作用。当覆盖度增加到一个满层,畴界不复存在,整个分子单层形成长程有序的消旋结构。此外,由于分子与半金属衬底之间较弱的相互作用,无论是侧躺的分子还是平躺的分子,都会受到针尖电场的影响发生移动或转动。上述研究结果为理解四联苯分子和半金属之间的相互作用,超分子手性和分子自组装结构之间的关联,以及制备长程有序的界面结构提供了重要信息。展开更多
Chiral S,P-donor ferrocene-derived ligands were synthesized and applied in the asymmetric hydrogenation of quinolines using the [Ir(COD)Cl]2/S,P-ligand c omplex a s the catalyst in the presence of iodine. The effects ...Chiral S,P-donor ferrocene-derived ligands were synthesized and applied in the asymmetric hydrogenation of quinolines using the [Ir(COD)Cl]2/S,P-ligand c omplex a s the catalyst in the presence of iodine. The effects of the solvent and hydroge n pressure on conversion and enantioselectivity were examined, and up to 82% ee was obtained. The planar chirality plays an important role in this reaction. R- and S-enantiomers of 1,2,3,4-tetrahydroquinoline derivatives were ob tained using ligands 3 and 5, respectively.展开更多
基金Acknowledgements This work was supported by the National Natural Science Foundation of China (Grant Nos. 11625416 and 11474064), the State Key Programs of China (Grant No. 2016YFA0300504), the Strategic Priority Research Program (B) of the Chinese Academy of Sciences (Grant No. XDB04040300), and the Youth Innovation Promotion Association of the Chinese Academy of Sciences (Grant No. 2016215).
文摘Both impurity- and magnetic-field-induced quasiparticle states in chiral p-wave superconductors are investigated theoretically by solving the Bogoliubov-de Gennes equations self-consistently. At the strong scattering limit, we find that a universal state bound to the impurity can be induced for both a single nonmagnetic impurity and a single magnetic impurity. Furthermore, we find that different chiral order parameters and the corresponding supercurrents have uniform distributions around linear impurities. Calculations of the local density of states in the presence of an external magnetic field show that the intensity peak of the zero-energy Majorana mode in the vortex core can be enhanced dramatically by tuning the strength of the external magnetic field or pairing interaction.
文摘To investigate the recovery of amino alcohols as chiral auxiliaries, optically active p-benzyloxyphenylglycinol and its corresponding oxazolidine of 1-naphthylcarboxaldehyde were prepared. Grignard additions to the oxazolidine followed by electrophilic quench and acidic hydrolysis afforded an aldehyde(compound 8)(later it was reduced to an alcohol, compound 9) in an excellent enantiomeric excess and a good recovery of the chiral amino alcohol. This research provides a model study of chiral amino alcohols in solid phase asymmetric synthesis.
基金the National Natural Science Foundation of China ! 29672031 Fang Min FU of Chengdu institute of or
文摘An improved procedure for the preparation of China, BAD(P)H model. (S_s)- 1 -benzyl-3- (p-tolylsulfinyl)-1.4-dihydropyridine with satisfactary chemical yield and excellent enantiopurity is reported.
文摘本文利用低温扫描隧道显微镜(low temperature scanning tunneling microscopy,LT-STM)研究了四联苯分子在半金属Bi(111)表面上的超分子手性及其自组装结构。在极低的覆盖度下,四联苯分子形成纳米尺度的分子团簇,团簇中的分子有平躺和侧躺的取向。随着覆盖度的增加,四联苯分子形成多畴的自组装单层结构。自组装单层的基本结构单元是由两个平躺分子和一个侧躺分子构成的三聚体。高分辩的STM图表明,平躺的四联苯分子表现出结构对称性,而侧躺的四联苯分子表现为四个之字形的突起,表明四个苯环之间发生了扭曲,使得三聚体团簇具有超分子手性。有趣的是,在畴区内部相邻两个三聚体的手性相反;在畴界两侧两个三聚体的手性相同,表明同手性的三聚体之间存在空间位阻作用。当覆盖度增加到一个满层,畴界不复存在,整个分子单层形成长程有序的消旋结构。此外,由于分子与半金属衬底之间较弱的相互作用,无论是侧躺的分子还是平躺的分子,都会受到针尖电场的影响发生移动或转动。上述研究结果为理解四联苯分子和半金属之间的相互作用,超分子手性和分子自组装结构之间的关联,以及制备长程有序的界面结构提供了重要信息。
文摘Chiral S,P-donor ferrocene-derived ligands were synthesized and applied in the asymmetric hydrogenation of quinolines using the [Ir(COD)Cl]2/S,P-ligand c omplex a s the catalyst in the presence of iodine. The effects of the solvent and hydroge n pressure on conversion and enantioselectivity were examined, and up to 82% ee was obtained. The planar chirality plays an important role in this reaction. R- and S-enantiomers of 1,2,3,4-tetrahydroquinoline derivatives were ob tained using ligands 3 and 5, respectively.