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Diastereoselective transformations of Leakadine were discovered: dimerization during melting or heating in CHCl3 with the formation of one diastereomer. The obtained dimer reacts with methyl isocyanate under mild conditions with the formation of an N-methylcarbamoyl derivative – also in the form of one diastereomer. In the diastereoselective reaction of Leakadine with dimethyl formamide dimethyl acetal, 2-dimethylamino-1,3-diazabicyclo[3.1.0]hexan-4-one was obtained. The reaction of Leakadine with perfluoroisobutylene was studied.

Chiral dialkyl- and tetraalkylglycolurils have been obtained using chiral (S)-(+)- and (R)-(-)-1-sec-butyl-3-methylurea as starting materials. The diastereomer (S)-(+)-2,6-di-sec-butyl-4,8-dimethyl-2,4,6,8-tetraazabicyclo[3.3.0]-octane-3,7-dione was separated into stereoisomers, for the higher melting of which the absolute configuration was determined as (S,S,S,S) by X-ray structural analysis.

Reaction of 1,10-bis(methoxymethyl)-1,10-diaza-18-crown-6 (1) with trimethylsilyl azide resulted in hitherto unknown 1,10-bis(azidomethyl)-1,10-diaza-18-crown-6 (2) and novel ionic compound 1,10-bis(azide anion)-1,10-dihydro-1,10-diaza-18-crown-6 (3). Compound 2 rnneacted with dimethyl acetylenedicarboxylate to give 1,10-bis(4,5-dimethoxycarbonyltriazolomethyl)-1,10-diaza-18-crown-6 (4). Carbamoylation of 1,10-diaza-18-crown-6 (5) with optically active α-phenylethyl amine yielded optically active 1,10-bis(α-phenylethylcarbamoyl)-1,10-diaza-18-crown-6 (6).

A new bicyclic aziridino lactone 1 was synthesized from methyl 2,3-dibromopropionate and 2-amino-2-methylpropane-1,3-diol (AMPD). The reaction of compound 1 with benzyl chloroformate and subsequent treatment of the intermediate compound with 1,8-diazabicyclo[5.4.0]undec-7-ene gave a bicyclic lactone, 4,8-dioxa-1-azabicyclo[4.3.0]nonane-3,9dione.

Chiral dialkyl- and tetraalkylglycolurils have been obtained using chiral (S)-(+)- and (R)-(-)-1-sec-butyl-3-methylurea as starting materials. The diastereomer (S)-(+)-2,6-di-sec-butyl-4,8-dimethyl-2,4,6,8-tetraazabicyclo[3.3.0]-octane-3,7-dione was separated into stereoisomers, for the higher melting of which the absolute configuration was determined as (S,S,S,S) by X-ray structural analysis.

By reactions of α,ω-diamines with 1,2-dihaloethanes there were synthesized α,ω-bis-N-aziridinoalkanes (la-g) and bis-N-aziridinoethyl ether (II). From 1,3-diaminopropane and dichloroethane bis-aziridine (III) was isolated in addition to (Ia). NMR spectra of the products were studied.

Derivatives of 1-fluoroaziridine-2,2-dicarboxylic acid have been synthesized for the first time and characterized by spectroscopic methods; nucleophilic reactions of dimethyl 1-fluoroaziridine-2,2-dicarboxylate, such as transesterification and amidation, occur predominantly at the carboxy group trans-oriented with respect to the N-substituent.

By reactions of α,ω-diamines with 1,2-dihaloethanes there were synthesized α,ω-bis-N-aziridinoalkanes (la-g) and bis-N-aziridinoethyl ether (II). From 1,3-diaminopropane and dichloroethane bis-aziridine (III) was isolated in addition to (Ia). NMR spectra of the products were studied.

Derivatives of 1-fluoroaziridine-2,2-dicarboxylic acid have been synthesized for the first time and characterized by spectroscopic methods; nucleophilic reactions of dimethyl 1-fluoroaziridine-2,2-dicarboxylate, such as transesterification and amidation, occur predominantly at the carboxy group trans-oriented with respect to the N-substituent.

1-Alkoxy-2,2-bis(trifluoromethyl)aziridines containing an ester group in the α position of the alkoxy substituent undergo nucleophilic substitution (ammonolysis and hydrolysis) with retention of the aziridine ring. The corresponding carboxylic acids, which were separated to give the antipodes with an optical purity of 95% through the diastereomeric salts with R- and S-α-phenylethylamine, were obtained.

1-Chloro-, 3-methyl-, 1-chloro-3-cyano-, 1-carbomethoxymethoxy-3-methyl-, and 1-carboxymethoxy-3-methyl-2,2-bis(trifluoromethyl)aziridines were synthesized for the first time. Criteria for distinguishing cis- and trans-3-substituted and 1,3-disubstituted 2,2-bis(trifluoromethyl)aziridines from the parameters of the 1H, 13C, and 19F NMR spectra were found.

1. Like monoaziridine analogs, bisaziridinomethoxymethane does not enter the amino-methylation reaction. 2. In bisaziridinomethoxymethane, an inhibited inversion of the N atom that is usual for N-alkylaziridines was shown to occur. 3. For the aziridines studied, a screening effect of the N-substituent relative to ring cis protons was found.

A new type of amine fragmentation under electron impact is elucidated for proline, sarcosine and aspartic acid derivatives and aminomethylphosphines of the general formula R2NCH2X. Ordinary α-cleavage affording the ion is suppressed by elimination of a neutral HX particle and [M - HX]+ ion formation, or M-HX neutral particle ejection and generation of an [HX]+ ion from [M]+˙. Such fragmentation is ensured by the presence of an α-heteroatom (N, O, P, S) in one substituent (X) and a CO2R type delocalizing group in the α-position of the other substituent (R2N).

3,3-Dimethyloxaziridine reacts with chloral and acetaldehyde to give crystalline N-(α-hydroxyalkyl)oxaziridines; the reaction with acetaldehyde is reversible. The N-aminomethylation of NH-oxaziridines is not realized, evidently because of the tendency of oxaziridines to iminate nucleophiles. The weakly nucleophilic chloromethylphthalimide and chloromethyl methyl ether give imidomethyl- and methoxymethyloxaziridines. 3,3-Dimethyldiaziridine reacts with excess chloromethyl methyl ether to give the N-monomethoxymethyl derivative. It is shown that α-hydroxyalkyloxaziridines and methoxymethyl-substituted oxaziridine and dizaridine do not enter into the aminomethylation of compounds with a labile hydrogen.

3,3-Bis(trifluoromethyl)-1-azirine, formed by the reaction of 1-arenesulfonyloxy-2,2-bis(trifluoromethyl)aziridines with nucleophilic reagents, reacts with aliphatic amines with ring-opening and formation of formamidines. With aziridines and diaziridines having a lower electron-donor capability of the nitrogen atom, it forms the adducts -2-aziridino- and -2-diaziridino-3,3-bis(trifluoromethyl)aziridines. All the isomers theoretically possible were recorded for these derivitives by the dynamic NMR method.

1. An efficient method of aziridine dimer synthesis is presented involving reaction of aziridine with esters of strong organic acids followed by alkaline hydrolysis of the resultant N-acyl derivatives. 2. New N-acyl and carbamoyl derivatives of aziridine dimer and trimer were synthesized. 3. Linear and branched isomers of aziridine tetramer and also diastereomers of 2-methylaziridine dimer were isolated and characterized. 4. An efficient regiospecific synthesis of 2,2-dimethylaziridine dimer and trimer was developed.

The optically active 1-acyl-substituted (1R,2R)-2-methyl- and (1R,2S)-2-methoxycarbonylaziridines were synthesized. The nonplanarity of the amide chromophore in them and its high conformational mobility, which was caused by the rotation around the N-C(O) bond, were shown on the basis of the investigation of the CD spectra and the calculations of simple models by the MNDO method. The possible correlation of the sign of the Cotton effect of the long-wave p-π* transition with the intrinsic chirality of the chromophore was studied.

1. 1-(Carbomethoxy)-2,2-bis(trifluoromethyl)aziridine was prepared and separated into antipodes. Derivatives of this compound were synthesized by modifying the CO2H group. 2. The nitrogen inversion barrier in l-alkoxy-2,2-bis(trifluoromethyl)aziridines is raised with increasing bulk of the 1-alkoxyl substituent.

1. The PMR spectra of 1-(α-phenylethyl)aziridine under conditions of slow nitrogen inversion show vicinal nonequivalence of the ring protons, which is greater for the protons trans to the N substituent. 2. The PMR spectra of dimethyl,β-(2,2-dimethylaziridLn-1-yl)succinate under the conditions of rapid nitrogen inversion show magnetic nonequivalence of the ring protons and methyl groups. 3. Acylation of methylphenylcyclopropylmethanol with bis(trifluoromethyl)ketene results in anionotropic rearrangement involving ring opening.

The fragmentation of compounds of the RN(CH2)nCHCOX (n=1–5) and RNCH2C(COX)2 type, where X=OAlk and NH2 and R=H, D, OAlk, and Cl, under electron impact was studied. When n=2–5, the chief fragmentation process is amine fragmentation, and the (M−COX)+ ion peak is the principal peak in the spectra at 30 and 12 eV. The fragmentation of three-membered heterocycles differs radically. The dominant fragmentation for 1-alkylaziridine-2-carboxylic and -2,2-dicarboxylic esters is splitting out of a radical from the ester group. This process is absent when R=H, D, C, and OAlk. Fragmentation with splitting out of the elements of alcohol for the esters and of ammonia for the amines is characteristic in the case of derivatives of 1-alkoxyaziridine-2-carboxylic and-2,2-dicarboxylic acids.

Distinct differences are observed on comparison of the fragmentation of tertiary amides (I to XI), and acylphosphines (XII to XVII) and (XX to XXII) under electron-impact, as well as of their vinylogues (XXIII to XXXI) and (XXXIV to XXXV).

1-Tosyloxy-2,2-bis(trifluoromethyl)aziridine with NaCN in DMSO gives 2,2-bis(trifluoromethyl)-3-cyanoaziridine, which is apparently formed via the intermediate 2,2-bis(trifluoromethyl)-1-azirine.

1. The reaction of hexafluoroacetone oxime with diazomethane gives the O-methyl derivative, reaction with carbamoyl chlorides and chlorocarbonic esters gives the carbamoyl and alkoxycarbonyl derivatives, while reaction with phosgene and thionyl chloride gives the carbonate and thionyl derivatives of the oxime. 2. Hexafluoroacetone oxime tosylate when treated with dimethylamine is cleaved to hexafluoroacetone dimethylhydrazone, while the corresponding urethylanes are formed when hexafluoroacetone methoxycarbony oxime is reacted with ammonia and dimethylamine.

1-Tosyloxy-2,2-bis(trifluoromethyl)aziridine with NaCN in DMSO gives 2,2-bis(trifluoromethyl)-3-cyanoaziridine, which is apparently formed via the intermediate 2,2-bis(trifluoromethyl)-1-azirine.

The fragmentation of compounds of the RN(CH2)nCHCOX (n=1–5) and RNCH2C(COX)2 type, where X=OAlk and NH2 and R=H, D, OAlk, and Cl, under electron impact was studied. When n=2–5, the chief fragmentation process is amine fragmentation, and the (M−COX)+ ion peak is the principal peak in the spectra at 30 and 12 eV. The fragmentation of three-membered heterocycles differs radically. The dominant fragmentation for 1-alkylaziridine-2-carboxylic and -2,2-dicarboxylic esters is splitting out of a radical from the ester group. This process is absent when R=H, D, C, and OAlk. Fragmentation with splitting out of the elements of alcohol for the esters and of ammonia for the amines is characteristic in the case of derivatives of 1-alkoxyaziridine-2-carboxylic and-2,2-dicarboxylic acids.

The reaction of N-ethyleniminosilanes with aldehydes is a convenient method of synthesis in a preparative sense ofα-N-ethyleniminoalkoxysilanes containing a nitrogen atom in theα-position to the oxygen atom.