MECHANISMS OF FREE-RADICAL REACTIONS. XXIV. QUANTITATIVE DESCRIPTION OF THE POLAR EFFECTS OF SUBSTITUENTS ON THE KINETICS OF THE FREE-RADICAL CHLORINATION OF ALIPHATIC COMPOUNDS BY N-CHLOROPIPERIDINE
The free-radical chlorination of 1-substituted alkanes with electron-withdrawing substituents by N-chloropiperidine in trifluoroacetic acid was studied by the method of competing reactions, and the relative rate constants were obtained for all positions of the substrates.The data on the position selectivity can be described satisfactorily by means of an electrostatic model of the polar effect of the substituent, calculated according to the Kirkwood-Westheimer equation.The obtained characteristics of the electrostatic effect can be successfully applied to calculation of the substrate selectivity and the intermolecular relative rate constants for all the positions, beginning with the third.The Taft equation is unsuitable for description of the effect of substituents on the reaction rate.
Dneprovskii, A. S.,Mil'tsov, S. A.,Arbuzov, P. V.
p. 1826 - 1835
(2007/10/02)
OXIDATIVE CHLORINATION OF ALKANONITRILES IN THE SYSTEM Na2S2O8 - CuCl2
-
Troyanskii, E. I.,Svitan'ko, I. V.,Ogibin, Yu. N.,Nikishin, G. I.
p. 2090 - 2094
(2007/10/02)
MECHANISMS OF FREE-RADICAL REACTIONS. XIV. SELECTIVITY OF FREE-RADICAL CHLORINATION OF VALERIC ACID DERIVATIVES WITH ARYLCHLOROIODONIUM CHLORIDES
The free-radical chlorination of C4H9Y compounds with arylchloroiodonium chlorides was investigated.The reaction of the secondary C-H bonds increases as they become further from the electronegative substituent.The reaction parameters were calculated from the ratio of the β- and γ-monochlorides by means of the Taft equation.The absolute value of ρ increases with the introduction of electronwithdrawing substituents into the arylchloroiodonium chloride molecule.
Dneprovskii, A. S.,Krainyuchenko, I. V.
p. 324 - 328
(2007/10/02)
Free Radical Substitution. Part 37. The Effect of Solvent on the Atomic Chlorination of 1-Substituted Butanes and Related Compounds
Experimental results reported in this paper show that the relative selectivity of atomic chlorination of 1-substituted butanes and related compounds is greatly influenced by the phase and by solvents.Solvents can be divided into three classes: (a) inert, (b) solvents which decrease the selectivity, and (c) solvents which increase the selectivity.The second group solvate the transition state and the third group solvate the chlorine atoms.
Potter, Alan,Tedder, John M.
p. 1689 - 1692
(2007/10/02)
More Articles about upstream products of 13249-56-4