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61.
N-Oligoethylene glycol monoaza crown ethers were prepared, and the notable effect of oxyethylene oxygen atoms of the side chain on complexing ability with sodium and potassium cations was confirmed. 相似文献
62.
N. Nakatsuji 《Chemical physics letters》1978,59(2):362-364
A method for excited states is given on the basis of the symmetry-adapted-cluster (SAC) expansion method. It is based on the fact that the SAC expansion method gives incidentally a set of excited functions which satisfies the Brillouin theorem with the ground state. 相似文献
63.
A variety of alkyl- or phenyl-substituted thia-crown ethers were prepared in two or three steps via bromoalkoxylation reactions of olefins. Dialkyl- and phenyl-substituted mono-and dithia-crown ethers were obtained as single compounds, whereas monoalkyl-substituted derivatives were a mixture of two positional isomers reflecting the isomeric mixture formation in the bromoalkoxylation reaction. 相似文献
64.
N-Cyano monoaza crown ethers were prepared by the reaction of cyanamide with oligoethylene glycol dichlorides or ditosylates in the NaH/DMSO reaction system and led to the derivatives. 相似文献
65.
Nakamura I Mizushima Y Yamamoto Y 《Journal of the American Chemical Society》2005,127(43):15022-15023
The PtCl2-catalyzed cyclization reaction of o-alkynylphenyl acetals 1 in the presence of 1,5-cyclooctadiene produces 3-(alpha-alkoxyalkyl)benzofurans 2 in good to high yields. For example, the reaction of acetaldehyde ethyl 2-(1-octynyl)phenyl acetal (1a), acetaldehyde ethyl 2-(cyclohexylethynyl)phenyl acetal (1c), and acetaldehyde ethyl 2-(phenylethynyl)phenyl acetal (1f) in the presence of 2 mol % of platinum(II) chloride and 8 mol % of 1,5-cyclooctadiene in toluene at 30 degrees C gave the corresponding 2,3-disubstituted benzofurans 2a, 2c, and 2f in 91, 94, and 88% yields, respectively. 相似文献
66.
A hierarchically organized architecture in multiple scales was generated from potassium hydrogen phthalate crystals and poly(acrylic acid) based on our novel biomimetic approach with an exquisite association of polymers on crystallization. 相似文献
67.
Cation radicals of cycloalkanes have been produced for the first time in γ-irradiated rigid solutions using fluoromethane as a matrix. Observed ESR spectra are analyzed by ab initio MO calculations; molecular geometries of the cations are optimized for several low-lying doublet states by the energy gradient method. Based on the optimized geometry thus determined the hyperfine splitting constants are calculated by the pseudo-orbital theory. Large Jahn-Teller distortions are calculated for the carbon rings and the H-C-H frames of the cation radicals. The distortions are consistent with the nodal picture of singly occupied orbitals. The calculated hfs constants are sensitive to the change in geometry due to a large contribution of spin-delocalization. The average of the calculated proton hfs constants is compatible with the observed ESR spectra which indicates that all the protons of the individual cations have become equivalent owing to the dynamic Jahn-Teller distortion. 相似文献
68.
69.
Yuya Mizuno 《代数通讯》2013,41(4):1654-1667
Inspired by τ-tilting theory [3], we introduce the notion of ν-stable support τ-tilting modules. For any finite dimensional selfinjective algebra Λ, we give bijections between two-term tilting complexes in K b (proj Λ), ν-stable support τ-tilting Λ-modules, and ν-stable functorially finite torsion classes in modΛ. Moreover, these objects correspond bijectively to selfinjective cluster tilting objects in 𝒞 if Λ is a 2-CY tilted algebra associated with a Hom-finite 2-CY triangulated category 𝒞. We also study some properties of support τ-tilting modules over 2-CY tilted algebras, and we give a necessary condition such that algebras are 2-CY tilted in terms of support τ-tilting modules. 相似文献
70.
Taiki Nakatomi Shoichi Koido Yuya Watabe Toshiyuki Takayanagi 《International journal of quantum chemistry》2019,119(11):e25908
The mechanisms including spin-inversion have been systematically studied for the M+ + OCS → MS+ + CO/MO+ + CS (M denotes a transition metal from Sc to Cu) ion-molecule reactions using the automated reaction path search method. We used the lowest mixed-spin potential energy surface obtained from the diagonalization of the spin-coupled Hamiltonian matrix, whose diagonal elements are taken to be the lowest two spin states. This scheme can effectively locate approximate minimum energy crossing points between the two potential energy surfaces with different spin multiplicities. The spin-orbit couplings at spin-inversion points have been calculated to understand the efficiencies of nonadiabatic transitions. The obtained reaction pathways and the calculated spin-orbit couplings are employed to interpret previous experimental studies. 相似文献