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Chemistry of Heterocyclic Compounds - Some electrophilic substitution reactions in the di(5-indolyl) oxide series were studied. The Vilsmeier and Mannich reactions and diazo coupling and...  相似文献   
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A new scheme for the mechanism of Fischer indolization of arylhydrazones has been suggested based on quantum-chemical calculations by the MNDO AM1 method.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 961–962, May, 1994.  相似文献   
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The heat of formation (H f) of unsymmetrical ketone phenylhydrazones and their enehydrazine tautomers was calculated by the semi-empirical quantum-chemical AM1 method. It is concluded that from H f values it is possible to judge the regioselectivity of indolization of unsymmetrical ketone phenylhydrazones.Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 1, pp. 220–221, January, 1993.  相似文献   
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We have carried out a correlation analysis of some physicochemical characteristics of pyrrole, pyrazole, imidazole, triazole, and tetrazole, calculated by the semiempirical quantum-chemical AM1 method. We have found the linear dependences of the ionization potential, the dipole moment, and the acidity on the -electron excess, and also the dependence of the ionization potential on the enthalpy of formation of the studied azoles.  相似文献   
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Coulomb Sturmians are obtained in prolate spheroidal coordinates by separation of variables in the Schrödinger equation and direct solution of the appropriate one-dimensional equations. Molecular orbitals are expressed as linear combinations of the introduced Coulomb Sturmians and some low-lying energy terms and corresponding wave functions are calculated for one-electron diatomic molecules. It is shown that similarity of the one- and two-centre orbitals in spheroidal coordinates, combined with completeness and good convergence properties of Coulomb Sturmians, substantially speeds up convergence and makes the calculated results closer to the exact ones. Application of the elaborated calculating scheme for diatomic many-electron molecules is discussed.  相似文献   
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