Chiroptical Properties and Conformation of 4,5-Saturated Derivatives of 5-Aryl-1,4-benzodiazepin-2-ones

CD spectra of a series of 5-aryl-7-chloro-l,3,4,5-tetrahydro- 2H-l,4-benzodiazepin-2-one derivatives having different substituents at positions 1, 3, 4, and 5 were studied. The absolute configuration at C-5 of two homochiral analogues, 1 and 2, having enantiomorphous ring conformations was determined on the basis of chiroptical correlations and theoretical calculations. The latter have shown that the optical activity mainly originates from the one-electron mechanism and is determined by the helicity of the diazepine ring, i. e. by the inherent chirality of the partial chromophore 4-chloro-N,2-dimethyl-formanilide. Exciton inter action s between transitions of the two arornatic chromophores A and C also give a significant contribution to chiroptical properties. By applying simple chiroptical rules dedueed from experimental spectra and supported by calculations, the stereochemistry (absolute conformation and configuration), of 3,5-disubstituted cis and trans epimeric pairs (7-17) was revealed

Chiroptical Properties and Conformation of 4,5-Saturated Derivatives of 5-Aryl-1,4-benzodiazepin-2-ones

CD spectra of a series of 5-aryl-7-chloro-l,3,4,5-tetrahydro- 2H-l,4-benzodiazepin-2-one derivatives having different substituents at positions 1, 3, 4, and 5 were studied. The absolute configuration at C-5 of two homochiral analogues, 1 and 2, having enantiomorphous ring conformations was determined on the basis of chiroptical correlations and theoretical calculations. The latter have shown that the optical activity mainly originates from the one-electron mechanism and is determined by the helicity of the diazepine ring, i. e. by the inherent chirality of the partial chromophore 4-chloro-N,2-dimethyl-formanilide. Exciton inter action s between transitions of the two arornatic chromophores A and C also give a significant contribution to chiroptical properties. By applying simple chiroptical rules dedueed from experimental spectra and supported by calculations, the stereochemistry (absolute conformation and configuration), of 3,5-disubstituted cis and trans epimeric pairs (7-17) was revealed

Distributed polarizability of the water dimer: Field-induced charge transfer along the hydrogen bond

The topological partitioning of electronic properties approach at Hartree-Fock level is used to investigate charge transfer response in a water dimer. Distributed polarizability components are employed to calculate the change in electron density under external fields. Field-induced charge flow between the water monomers is most significant along the direction of the hydrogen bond. The molecular polarizability of the molecules in the dimer is reduced owing to formation of the hydrogen bond

Distributed first and second order hyperpolarizabilities: An improved calculation of nonlinear optical susceptibilities of molecular crystals

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