A study of dipole moments of substituted isothiocyanates of 1,3-diphenyl-2-propen-1-one

1984 ◽  
Vol 49 (10) ◽  
pp. 2382-2386 ◽  
Author(s):  
Gejza Suchár ◽  
Milan Dzurilla ◽  
Pavol Kristian
Keyword(s):  
Electronic Structure ◽  
Benzene Solution ◽  
Dipole Moments ◽  
Vector Addition

The dipole moments have been measured of various substituted isothiocyanates of 1,3-diphenyl-2-propen-1-one in benzene solution. The measured values have been compared with the dipole moments obtained by the vector addition of the bond dipole moments, and the comparison has been used for a discussion of their electronic structure and interactions of the NCS group.

Electric Dipole Moments of Some Heterocyclic Cyclobutane Derivatives in Benzene Solution

1979 ◽  
Vol 34 (2) ◽  
pp. 257-259
Author(s):  
M. Sanesi
Keyword(s):  
Electric Dipole ◽  
Benzene Solution ◽  
Dipole Moments ◽  
Electric Dipole Moments ◽  
Vector Addition ◽  
Cyclobutane Derivatives

Abstract The electric dipole moments of some heterocyclic cyclo-butane derivatives have been measured in benzene solution at 20 °C. The observed values are compared with those calculated by vector addition for different steric configurations

Conformation and electronic structure of aromatic chloroformates

1987 ◽  
Vol 52 (4) ◽  
pp. 970-979 ◽  
Author(s):  
Otto Exner ◽  
Pavel Fiedler
Keyword(s):  
Electronic Structure ◽  
Oxygen Atom ◽  
Strong Interaction ◽  
Electron Distribution ◽  
Room Temperature ◽  
Functional Group ◽  
Dipole Moments ◽  
Carbonyl Oxygen ◽  
Nonpolar Solvents ◽  
Single Method

Aromatic chloroformates Ib-Ie were shown to exist in the ap conformation, in agreement with aliphatic chloroformates, i.e. the alkyl group is situated cis to the carbonyl oxygen atom as it is the case in all esters. While 4-nitrophenyl chloroformate (Ie) is in this conformation in crystal, in solution at most several tenths of percent of the sp conformation may be populated at room temperature and in nonpolar solvents only. A new analysis of dipole moments explained the previous puzzling results and demonstrated the impossibility to determine the conformation by this single method, in consequence of the strong interaction of adjoining bonds. If, however, the ap conformation is once proven, the dipole moments reveal some features of the electron distribution on the functional group, characterized by the enhanced polarity of the C-Cl bond and reduced polarity of the C=O bond. This is in agreement with the observed bond lengths and angles.

Dipole Moments of para-Substituted N-Phenylsulfonyl-N'-Allylthioureas

1995 ◽  
Vol 60 (5) ◽  
pp. 856-862
Author(s):  
Gejza Suchár ◽  
Ivan Danihel
Keyword(s):  
Dipole Moments ◽  
Vector Addition ◽  
Stretching Vibrations

Dipole moments of a series of para-substituted N-phenylsulfonyl-N'-allylthioureas were determined. Comparison of the experimentally found dipole moments with those calculated by vector addition of bond and group moments has shown that (E) conformation at the N-C bonds is preferred. The same result was obtained from the N-H stretching vibrations. The results are compatible with a synperiplanar arrangement at the C-C bond of the allyl moiety.

Dipole moments induced in larger molecule. Long-chain aliphatic esters

1982 ◽  
Vol 47 (1) ◽  
pp. 29-34 ◽  
Author(s):  
Otto Exner ◽  
Ayfer Bapçum
Keyword(s):  
Benzene Solution ◽  
Dipole Moments ◽  
Straight Chain ◽  
Basic Assumptions ◽  
Donor Acceptor ◽  
Eyring Theory ◽  
Aliphatic Esters ◽  
Long Chain

Dipole moments of straight-chain aliphatic esters Ia-Ic and IIa-IIf were measured in benzene solution. The observed trends are poorly reproduced by the classical Smith-Eyring theory; the reason may be partly the unknown conformation, partly even donor-acceptor complexes with the solvent. No deviations were observed with the highest members of the series, attributable to violation of some basic assumptions of the theory of dielectrics.

Dipole moments and conformation of α-disulphones. The gauche effect

1985 ◽  
Vol 50 (10) ◽  
pp. 2245-2251 ◽  
Author(s):  
Otto Exner ◽  
Václav Jehlička
Keyword(s):  
Dihedral Angle ◽  
Graphical Method ◽  
Benzene Solution ◽  
Dipole Moments ◽  
Statistical Treatment ◽  
X Ray ◽  
Gauche Effect

The dipole moments of substituted diphenyl disulphones I-III were measured in benzene solution and interpreted by the previously described graphical method. The results suggest an equilibrium of the ap and sc conformations in the ratio 3 : 1, at variance with various empirical rules and theories of the so-called gauche effect. A statistical treatment of X-ray data of various sulphonyl derivatives revealed essentially two preferred conformations: the more stable sc, with a broadened dihedral angle, and the less stable ap.

PHOSPHONITRILIC COMPOUNDS: PART I. THE MECHANISM OF PHOSPHONITRILIC CHLORIDE POLYMERIZATION CAPACITANCE, CONDUCTANCE, AND ELECTRON-SPIN RESONANCE STUDIES

1964 ◽  
Vol 42 (2) ◽  
pp. 447-455 ◽  
Author(s):  
H. R. Allcock ◽  
R. J. Best
Keyword(s):  
Free Radicals ◽  
Electron Spin Resonance ◽  
Electron Spin ◽  
Benzene Solution ◽  
Dipole Moments ◽  
Ring Cleavage ◽  
Preliminary Step ◽  
Polymerization Mechanism ◽  
Spin Resonance ◽  
Nitrogen Ring

Capacitance and conductance measurements were carried out with molten (NPCl2)3 and [NP(OC6H5)2]3 and dipole moments were determined in benzene solution. Attempts to detect free radicals in molten samples of the same compounds were unsuccessful. Evidence was obtained that homolytic or heterolytic phosphorus–nitrogen ring cleavage is not involved in the primary initiation process. The results favor, instead, a polymerization mechanism for (NPCl2)3 in which phosphorus–chlorine ionization is a preliminary step.

Sign in / Sign up

Export Citation Format

Share Document