E. I. Strunskaya

Jacobsen-type enantioselective hydrolysis of aryl glycidyl ethers. 31P NMR analysis of the enantiomeric composition of oxiranes

The enantioselective partial hydrolysis of a number of racemic aryl glycidyl ethers in the presence of chiral Co(salen)-catalyst was studied. The enantiomeric composition of the isolated (R)-aryl glycidyl ethers was analyzed by 31P NMR using optically active substituted 2-chloro-1,3,2-dioxaphospholanes. A synthesis of β-adrenoblocking agents (S)-toliprolol and (S)-moprolol based on the simultaneously obtained (S)-3-aryloxypropane-1,2-diols was proposed.

Synthesis of aryloxy-substituted 1,2,5-thiadiazoles by the Ullmann reaction

Abstract3-Aryloxy-1,2,5-thiadiazoles were synthesized by the Ullmann reaction either from 3-chloro-1,2,5- thiadiazoles and phenols having donor substituents or from 3-hydroxy-1,2,5-thiadiazoles and chlorobenzenes containing acceptor substituents.

Electrochemical reduction and oxidation of 3,4-disubstituted 1,2,5-thiadiazoles

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.

Cyclic phosphorochloridites (chloridates) based on chiral butane-2,3-diol and dihydrobenzoin as reagents for the analysis of enantiomeric compositions of alcohols by31P NMR spectroscopy

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.

New reaction of glycidols with oxalyl chloride and phosgene—an approach to cyclic esters

Abstract2,3-Epoxy alcohols (glycidols) react with carboxylic acid dichlorides to form cyclic esters of 3-chloro-1,2-diols. The reaction proceeds with complete retention of the configuration of the C(2) atom of the initial glycidol and with predominant (but not complete) inversion of the configuration of the C(3) atom in the final heterocycle.

(4R,5R)-Bis(N,N-dimethylaminocarbonyl)-2-chloro-1,3,2-dioxaphospholane: A convenient reagent for control of enantiomeric composition of chiral alcohols by31P NMR spectroscopy

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.

Metal complex electrocatalytic reduction of 1,1-dihalocyclopropanes

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.

A Comparative Study of the Cyclic Chlorophosphites with C2-Symmetrical Organic Fragments as the Reagents for Enantiomeric Composition Control of the Chiral Alcholos

Abstract The 31P NMR method is intensively used for enantiomeric composition control during the last years [1]. Among all other derivatizing agents the C2-symmetrical ones have some advantages.