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[3+2] Cycloaddition reactions of polyfluoroalkanethioamides with nitrile imines, generated in situ by dehydrochlorination of the corresponding hydrazonoyl chlorides, in the presence of triethylamine, were studied. A new method was proposed on the basis of these reactions for the synthesis of 2-polyfluoroalkyl-2,3-dihydro-1,3,4-thiadiazoles.

The facile method of generating internal chirality into the calixarene with two hydroxy groups at the lower rim via an attached chiral substituent has been proposed. The reaction with acylisocyanates, catalyzed by a small amount of triethylamine, proceeds forming predominantly one of the two possible calixarene carbamates. The best diastereomeric excess (60 %) has been achieved in the reaction of trichloroacyl isocyanates with 1,3-hydroxycalixarene substituted with the chiral phenylethyl amide moiety. The individual diastereomers of trichloroacetyl-carbamoylcalix[4]arenas were isolated by crystallization, and their absolute configuration was determined by X-ray diffraction study. The most favored conformations predicted for 1,3-dihydroxy calixarene structures by quantum chemical calculations possess very similar stability. However, the triethylamine molecule preferably connects to the one hydroxyl group of the two available ones, providing the most favorable adduct, which predominantly participates in the reaction with acylisocyanates. This gives rise to the observed diastereomeric excess. The subsequent treatment of the formed carbamoyl with n-propyl bromide in presence of NaH and hydrolysis of the product of alkylation easily provide a persistent internally chiral calixarene.

Potential atropisomeric ligands, diphenylphosphane derivatives of bis-triazoles, were synthesized by direct phosphanylation of the starting bis-triazoles with chlorodiphenylphosphane. Their crystal structure was elucidated by X-ray diffractional analysis. The conformations of these compounds were modeled by DFT calculations.

Alkylation, by ω-haloalkylphosphonates, of the Ni(II) complex of the Schiff base formed from glycine and (S)-2-N-(N1-benzylprolyl)-o-aminobenzophenone has been used for the asymmetric synthesis of (S)-2-amino-4-phosphonobutyric and (S)-2-amino-5-phosphonovaleric acids.

Amidoalkylation of 2-thiouracil with 1,2,2,2-tetrachloroethylamides in the presence of triethylamine or sodium hydroxide gives products of S-, O-, and N-substitution, depending on the reaction conditions.

A convenient method is proposed for the preparative synthesis of pure diastereomers and enantiomers of fluoro-substituted (2S,3R)- and (2R,3R)-β-phenylserines by the hydroxyalkylation of the Ni(II) — complex of the Schiff base of glycine with (S)-2-N-(N1-benzylpropyl)aminobenzophenone using the corresponding fluoro-substituted benzaldehydes.

The diastereo- and enantioselective synthesis of the previously unknown 2(R), 3(S)-Β-phenylserines containing fluorine atoms, the O-CHF2-, O-CF3-, and CF3 groups in the benzene ring, was carried out by alkylation of a Ni(II) complex of a Schiff base of glycine with (S)-2-N-(N'-benzylprolyl)aminobenzophenone by fluorine-substituted benzaldehydes. The factors influencing the stereochemical result of the reactions studied are not the steric characteristics of the substituents in benzaldehydes, but their electronic nature.

Alkylation of trans-N-alkyl(or aryl)-N'-(3-hydroxy-1,1-dioxothiolan-4-yl) thioureas with ethyl p-toluenesulfonate, and the reaction of cyanogen bromide wiht an ethyl p-toluenesulfonate, and the reaction of cyanogen bromide with trans-3-hydroxy-4-aminothiolan-1,1-dioxides have given salts of trans-2-iminoperhydrothieno[3,4-d]-oxazole 5,5-dioxides. Rearrangement of these oxazolidines in the presence of bases afford perhydrothieno[3,4-d]imidazole-2-one 5,5-dioxides.

Reaction of trans-3-chloro-A-aminothiolane 1,1-dioxide hydrochloride with aryl isothiocyanates gives, according to the base involved, cis-perhydrothieno[3,4-d]imidazole-2-thione 5,5-dioxides or the hitherto undescribed cis-2-aryliminoperhydrothieno 3,4-d] thiazole 5,5-dioxides.

Examination of the PMR spectra of eleven bicyclic thiolane 1,1-dioxide derivatives has enabled those features of the spectral parameters characteristic of the cis- and trans-orientation of the two condensed five-membered heterocycles to be established. The proton coupling constants show that the conformation of the 1,1-dioxothiolane ring in both types of compound in solution differs from that in the crystalline state, as determined by x-ray analysis.