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951.
Suzuki T Kanno Y Morioka Y Kuroda K 《Chemical communications (Cambridge, England)》2008,(28):3284-3286
The alignment of mesochannels in a mesoporous silica film on a freshly cleaved mica surface, prepared by an evaporation-induced self-assembly process, is unexpectedly found to be unidirectional with the narrowest directional distribution. 相似文献
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Novel carboxylic acid derivatives were synthesized, which allowed switching of the intramolecular distance between amide group and carboxylic oxygen atoms using E to Z photoisomerization of the cinnamate framework. An intramolecular NH...O hydrogen bond was formed in the Z carboxylate compound not only in solution but also in the solid state. The pK(a) value of the carboxylic acid was lowered as a consequence of the E/Z photoisomerization. 相似文献
959.
Kunihiko Takabe Takashi Yamada Takenori Miyamoto Nobuyuki Mase 《Tetrahedron letters》2008,49(41):6016-6018
Acid promoted cyclization of the geranylamine N-oxide (E)-4 followed by base-catalyzed intramolecular aldol condensation afforded 1-acetyl-4,4-dimethyl-1-cyclohexene (7) in one-pot operation. Reduction of 7, which possess strong fruity odor, followed by lipase-catalyzed kinetic resolution furnished the acetate (R)-26 (>49.9% yield, >99% ee) and the recovered alcohol (S)-25 (>49.9% yield, >99% ee, herbal odor). 相似文献
960.
A theoretical investigation of the X(2)A" and A(2)A' electronic states of the HO(2) radical is reported. Both electronic states have nonlinear equilibrium geometries and they correlate with a (2)Pi state at linear geometries so that they exhibit the Renner effect. In highly excited bending states, there is tunneling between two equivalent minima (with geometries where the H nucleus is bound to one, or the other, of the two O nuclei), and the two linear geometries H-O-O and O-O-H become accessible to the molecule. Thus, HO(2) affords an example of the so-called double Renner effect. Three-dimensional potential energy surfaces for the X(2)A" and A(2)A' electronic states of HO(2) have been calculated ab initio and the global potential energy surfaces for the states have been constructed. These surfaces have been used, in conjunction with the computer program DR [Odaka et al., J. Mol. Structure 795, 14 (2006); Odaka et al., J. Chem. Phys. 126, 094301 (2007)], for calculating HO(2) rovibronic energies in the "double-Renner"-degenerate electronic states X(2)A" and A(2)A'. The results of the ab initio calculations, the rovibronic energies obtained, and analyses of the wavefunctions for selected states are presented. 相似文献