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1.The formation of protonated and free Schiff's bases from S-alanine and salicylaldehyde was studied quantitatively by the PMR method in the interval of pD 9.0–12.0.2.The rate constants of the racemization of S-alanine and its Schiffs base with salicylaldehyde protonated at the nitrogen were determined, and they were compared with the analogous constants for N-salicyl-idene-S-alaninate complexes of Cr(III), Rh(III), and Co(III) and the Schiffs base from pyridoxal and S-alanine.3.The basic role of the metal in the model reactions consists of increasing the concentration of reactive particles in solution as a result of coordination of the Schiffs base with the metal ion.

Conclusions 1.The kinetics of the decomposition of 1-diethylamino-2,2-dinitropropane in solutions of H2SO4 was studied at various temperatures and acidities of the medium. Replacement of the leaving group with (CH3)2· by leads to a 6000-fold increase in the rate of decomposition.2.The dissociation constants of the conjugate acids of 1-dimethylamino-2-methyl-2-nitropropane, 1-diethylamino-2-methyl-2-nitropropane, 1-diisopropylamino-2-methyl-2-nitropropane, and 1-diethylamino-2,2-dinitropropane in acetonitrile at 25° were determined.3.The absorption of theß-nitroamines studied in the region of 240–360 nm characterizes the presence of some intermolecular interaction between the amino and nitro groups in these compounds.

1.The dissociation ofa-nitro-ß-hydroxybutyric ester (I),a-nitro-a-methyl-ß-hydroxybutyric ester (II),a-nitro-a-methyl-ß-hydroxypropionic ester (III), and 3-nitro-3-methylbutanol-2 (IV) to the starting materials in water under the action of bases was studied.2.The equilibrium constants of the dissociation of (II), (III), and (IV) in water at 25°C were determined.3.The rate constants of the interaction of the anion of nitropropionic ester with acetaldehyde and formaldehyde and the anion of 2-nitropropane with acetaldehyde were determined.

1.The presence of a correlation between the basicity with respect to hydrogen of carbanions of nitrocompounds and their basicity with respect to carbon in the reaction series of acetaldehyde and formaldehyde was demonstrated.2.The basicity of carbanions with respect to carbon in the series of acetaldehyde is two orders of magnitude less than the basicity of the same carbanions in the series of formaldehyde. This phenomenon was explained from the standpoint of differences in the steric stress in the molecules of the nitroalcohols formed by condensation of the nitro-compounds with acetaldehyde and formaldehyde.3.The nucleophilicity of anions of nitro-compounds with respect to carbon varies correspondingly to the nucleophilicity of these anions with respect to hydrogen.

1.The kinetics of the decomposition of 1-dimethylamino-2-methyl-2-nitropropane and 1-diisopropyl-amino-2-methyl-2-nitropropane in water at various temperatures and pH of the medium was investigated. The dissociation constant of the conjugated acid of 1-dimethylamino-2-methyl-2-nitropropane was determined at 25° andµ=0.1. The dissociation constant of the conjugated acid of 1-diisopropylamino-2-methyl-2-nitropropane and the true rate of decomposition of this compound at 25° were estimated on the basis of the correlation equations.2.The values of the true rate constants of the decomposition of the nonprotonated form of 1-dimethylamino-2-methyl-2-nitropropane and l-diethylamino-2-methyl-2-nitropropane were determined at various temperatures. The values of the enthalpy and entropy of activation of cleavage of the C-C bond in 1-dimethylamino-2-methyl-2-nitropropane and l-diethylamino-2-methyl-2-nitropropane were determined.

1.In aqueous solution the Mannich reaction proceeds according to an ionic mechanism, proposed by Lieberman and Wagner. The reaction mechanism remains the same in acid and alkaline medium.2.The basicity constants and rate constant of cleavage of the C-C bond of 1-diethylamino-2-methyl-2-nitropropane were determined, along with the entropy and enthalpy of activation of cleavage of the C-bond for this compound.

1.The reactions of potassium alkoxides with the corresponding alcohols, witha-methylstyrene, and with allyl alcohol were studied.2.When heated with the corresponding alcohols, secondary alkoxides eliminate hydrogen and are converted into ketones.3.The hydride ion eliminated from alkoxides can add to the double bonds ofa-methylstyrene and allyl alcohol.4.A new type of isotopic hydrogen exchange reaction was discovered: its consists in the nucleophilic replacement of a hydrogen atom in theß -position to the negatively charged center by a deuteride (hydride) ion.

1.A study was made of the reactions of 1-methylpentylmagnesium bromide, 1-methylpentylmagnesium chloride, and 1-methylpentyllithium with t-butyl methyl, t-butyl ethyl, t-butyl isopropyl, di-t-butyl, and t-butyl phenyl ketones.2.With change in the structure of the alkyl group of the ketone, and also with change in the type of organometallic compound, the relative amounts of cis-2- and trans-2-olefins and of total 2-olefins and total 1-olefins in the reaction products also change. This indicates that orientation in the elimination of the hydride ion is determined by steric requirements imposed on the transition state.3.A hypothesis is advanced concerning the structure of the transition state in the hydride ion elimination reaction.

Summary Based on n-butyl, n-propyl, and ethyl chlorides as examples, it was established that these alkyl chlorides, in the absence of tertor sec-alkyl chlorides, do not undergo hydrogen exchange reaction with deuterium chloride in nitrobenzene solution in the presence of aprotic acids. Under these conditions, n-BuCl and n-PrCl are isomerized to secondary alkyl chlorides, which easily undergo the hydrogen exchange reaction.