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Racemic and enantiopure cis-and trans-4-(1-naphthyloxy)methyl-2-oxo-1,3,2-dioxathiolanes were studied by X-ray diffraction. The factors responsible for their crystal packings were revealed. The conformation of the exocyclic fragment varies from synclinal to antiperiplanar depending on both the local (cis-trans isomerism of the molecule) and external (homochiral/heterochiral environment) stereochemical factors. Data on the structures of five-membered sulfites in crystals were generalized. It was concluded that the heterocycle has considerable conformational flexibility.

Specific features of melting of crystalline samples of 3-(2-R-phenoxy)propane-1,2-diols with different enantiomeric compositions were studied by differential scanning calorimetry. The melting points and enthalpies of melting for the racemate and individual stereoisomers were determined. Binary phase diagrams were constructed. The entropy of mixing of individual enantiomers in the liquid phase and the free energy of formation of the racemic compound were calculated. The thermochemical data indicate that the racemates are formed upon the crystallization of phenoxy-and 2-fluorophenoxy-containing compounds, while crystallization of the chloro-, bromo-, and iodo-substituted analogs would form racemic conglomerates.

Catalytic electroreduction of several substituted gem-dihalocyclopropanes was studied in the presence of metal salen-complexes by polarography, cyclic voltammetry, and preparative electrolysis. Monohalocyclopropanes (54—59%) and the corresponding allene (5—9%) were the main reduction products. The reaction rate constants were determined. The inner-sphere electron transfer was shown to occur under these conditions.

Crystalline specimens of homochiral and racemic glycidyl p-toluenesulfonate were studied by IR spectroscopy, differential scanning calorimetry, and X-ray diffraction analysis. The melting phase diagram of glycidyl p-toluenesulfonate was constructed. The stacking effect in the crystals of the racemic sulfonate is responsible for a more dense molecular packing, with the result that a heterochiral type of crystallization becomes more favorable.

The data from IR spectroscopy, differential scanning calorimetry, and X-ray diffraction analysis are compared for crystalline specimens of homochiral and racemic propranolol and its hydrochloride. The stabilities of the racemates were quantitatively characterized and the factors responsible for the order of their stability are revealed.

The character of the first stage of reduction of 5-X-5-nitro-1,3-dioxanes 1—10 and 2-X-2-nitro-1,3-propanediols 11 and 12 is independent of the nature of halogen (X = Br, Cl) and substituents in position 2 of the dioxane cycle. The transfer of two electrons to a molecule of compound 1—12 is accompanied by the anionoid elimination of halogen and formation of the anion of nitronic acid. The high mobility of halogen is mainly due to the acceptor nitro group capable of further transformations in the α-position to halogen. The direction of further reduction involving the electron transfer to electrochemically active groups in the aromatic fragment of the molecule is determined by the nature of these groups. Chloro-, bromo-, and iodophenyl-substituted derivatives 4, 5, and 8—10 are reduced as typical halobenzenes. In the case of nitrophenyl-substituted compounds 3 and 7, the dioxane cycle opens to form dianions of p- and m-nitrobenzaldehydes along with the reduction of the nitroso group through the stages of formation of the radical anion and radical anion of the nitroso group. The radical anions of the nitro and nitroso derivatives were identified by ESR.

Nonracemic β-blockers, viz., (S)-propranolol and (S)-timolol, were prepared from (S)-glycidol in three steps consisting in the reaction with SOCl2 followed by the reaction of the resulting (4S)-4-chloromethyl-2-oxo-1,3,2-dioxathiolanes with the corresponding phenol and the final cleavage of (4R)-aryloxymethyl sulfites under the action of amines in DMF.

Reactions of 2,3-epoxyalcohols (glycidols) with thionyl chloride or sulfuryl chloride afford cyclic sulfites or sulfates, respectively. These reactions yield predominantly 4-chloroalkyl-1,3,2-dioxathiolane oxides. The configuration of the C(4) atom in the latter compounds exactly corresponds to that of the C(2) atom of the parent glycidol, whereas the configuration of the exocyclic atom is almost completely reversed with respect to that of the C(3) atom of the precursor.

The use of cyclic phosphorochloridites which were prepared based on PCl3 and chiral butane-2,3-diol or hydrobenzoin as possible reagents for the analysis of the enantiomeric composition of chiral alcohols by31P NMR spectroscopy is considered. The diastereomeric dispersion of chemical shifts of the resulting phosphites as well as of derived phosphates and thiophosphates is compared with that of structurally similar reagents.

Some aspects of phosphorylation of 2,2′-dihydroxy-1,1′-binaphthalene (BINOL) and 1,4∶3,6-dianhydro-d-mannitol (isomannide) were investigated. The possibility of using the corresponding cyclic chloro- and amidophosphites for the analysis of enantiomeric compositions of chiral primary and secondary alcohols by31P NMR was examined.

The use of enantiomerically pure cyclic chlorophosphite obtained by the reaction of PCl3 withN,N,N′,N′-tetramethyldiamide of naturall-(+)-tartaric acid for analysis of the enantiomeric composition of chiral primary and secondary alcohols by31P NMR spectroscopy is considered.