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The stereoisomers of 5-phenoxy-1,3,2-dioxathiane 2-oxide both exist as chair conformers with an axial S = O bond. The features of conformational behavior, distinguishing this diastereomeric pair from earlier studied are explained in terms of the conformational energies of substituents in the 1,3-dioxane series.

The reaction of 2-phenyl-1,3,2-dioxaphospholane with HCl gives a mixture of phenylphosphinic acid, bis(2-chloroethyl) phenylphosphonate, and phenylphosphine; therewith, intermediate oligomeric phosphonites, hydrophosphoryl compounds, and phosphoranes were detected. Thermal treatment of the reaction mixture results in formation of ethylene phenylphosphonate and (2-chloroethyl)phenylphosphinate.

The electron-acceptor nitrogen and sulfur atoms in 3,4-disubstituted 1,2,5-thiadiazoles are responsible for much decreased reduction potentials and much increased oxidation potentials of these compounds compared with the corresponding carbocyclic derivatives. The thiadiazole ring is resistant to oxidation, and the reversible electron transfer gives rise to fairly stable radical cations. Reductive stability of the heterocycle depends on the nature of its substituents and on the medium: When nucleofuge substituents are present, two-electron transfer in aprotic media results in heteroring opening with iminonitrile formation, whereas in the presence of two readily leaving groups, the electron transfer induces cleavage of the complete heteroring into inorganic anions.

The regioisomeric composition of the adducts of unsymmetrical oxiranes with achiral and chiral phosphorochloridites was studied. Factors allowing enantiomeric assessment of chiral oxiranes with the aid of chiral derivatizing organophosphorus reagents were revealed.

Scalemic diethyl phosphates of glycerol and glycidol were prepared by partial enantioselective hydrolysis of racemic glycidyl diethyl phosphate in the presence of chiral Co(salen) catalyst. The enantiomeric composition of the products was analyzed by 31P NMR spectroscopy with organophosphorus reagents.