Polarity,polarizability, and structure of esters. 8. Relationships in spatial structure and electrooptical characteristics of esters of benzoic acids

Average structural characteristics of esters of benzoic acids have been found by statistical treatment of crystallographic data. A general procedure has been developed for determining electrooptical parameters that are optimal for a series of molecules with C_s symmetry. In a series of methyl benzoates p-R-C₆H₄-COOCH₃, the index ellipsoid of the unsubstituted molecule is characterized by semiaxes b₁=14.89, b₂=18.74, b₃=9.27 ų; here, the b₂ axis deviates by 5° from the C-R axis.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 795–801, April, 1991.     

Polarity,polarizability, and structure of esters 7. Electronic and steric structure of clcoocclnh3-n chlorinated chloroformates

Mono-, di-, and trichloromethyl chloroformates were investigated by dipole moments, Kerr effect, and nuclear quadrupole resonance (NQR) methods. It was determined that chloromethyl chloroformate exists in solution in synclinal conformation with respect to the O-C_sp bond with COCCl dihedral angle 90±10°. The n, interaction occurring in it is close in magnitude to that in chloroalkyl formates and acetates. Dichloromethyl chloroformate exists in the crystal in the sc, ap conformation at the O-C_sp bond. In chlorinated chloroformates, the orbital n, and n, interactions are in a state of competition.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 413–417, February, 1991.     

Polarity,polarizability, and stereochemical structure of N-phthalimidyl disulfides

Conclusions Orientations close to orthogonal are realized for the Pht and Ar groups in relation to the planes of the NSS and SSC bonds in the investigated disulfides in dioxane solutions. The dihedral angle is =90 ± 15°.Translated from Izvestiya Akademii Nauk SSSR. Seriya Khimicheskaya, No. 9, pp. 1988–1992, September, 1987.     

Polarity,polarizability, and structure of esters. 6. Conformations of para-substituted phenyl chloroformates in solutions

The ellipsoid of polarizability of the chloroformate fragment ClC(O)O has principle semiaxes b₁=3.64, b₂=5.34, b₃=3.81 Å₃; the angle between b₁ and the C=0 bond is 24.5°. Aromatic chloroformates in solutions exist in conformations with cisoid position of the C=O and O-R bonds and the phenoxyl fragment in aromatic chloroformates deviates from the plane of the molecule.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2704–2708, December, 1989.The authors wish to thank S. G. Vul'fson for assistance in measuring the depolarization of Rayleigh light scattering.     

Polarity,anisotropy of polarizability,and steric structure of two tetrahalonorcaranes

Conclusions On the basis of the dipole moments and Kerr constants of trans-3,4,7,7-tetrabromobicyclo[4,1,0]heptane and trans-3,4-dibromo-7,7-dichlorobicyclo[4,1,0]heptane, it was established that the most stable conformation is an anti-boat with a two-faced angle between the planes 2-3-4-5 and 5-6-1-2 of 200–215°.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2231–2234, October, 1973.     

Polarity,polarizability and steric structure of 2,2-dichlorovinyl alkyl ethers

Conclusions In solutions of 2,2-dichlorovinyl alkyl ethers, the s-trans conformation or a very similar conformation is realized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 557–559, March, 1986.     

Polarity and polarizability of alkoxyacetylenes

Conclusions The dipole moment of the C_sp-O bond in alkoxyacetylenes is 1.3 D and is directed toward the carbon atom. The values for the major semiaxes in the polarizability ellipsoid of the HC=CO fragment are b_L=4.60 and b_T=bv=2.77 ų.Translated from Izvestiya Akaderaii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1198–1200, May, 1986.     

Polarity,polarizability anisotropy,and conformation of some furylcyclopropanes

Conclusions In the molecules of 1-(2-furyl)-2,2-dichlorocyclopropanes the three-membered ring and oxygen atom have a syn (or close to it) orientation.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2368–2371, October, 1977.