Effective synthesis of non-racemic prenalterol based on spontaneous resolution of 3-(4-hydroxyphenoxy)propane-1,2-diol

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(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. Translated fromIzvestiya Akademii Nauk., Seriya Khimicheskaya, No. 1, pp. 172–175, January, 1998.     

Synthesis and x-ray structural examination of intracomplex boroxadiazolidines

The reaction between acetone monoalkylhydrazones and aldehydes in the presence of boric acid derivatives has given five-membered boron-nitrogen heterocycles, the stability of which is to a large extent dependent on the substituents in the ring. An x-ray structural examination of the boroxadiazolidine (VI) has been carried out.Deceased.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 178–182, January, 1991.     

5-(Thiazol-4-yl)-1,2,4-triazoles

By reaction of arylhydrazones of benzoyl chloride with 4-aminomethylthiazole in the presence of triethylamine, the corresponding amidrazones were obtained, which upon oxidation gave 5-(thiazol-4-yl)-1,2,4-triazoles with fungicidal and bactericidal activity.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2111–2112, September, 1991.     

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.     

From racemic compounds through metastable to stable racemic conglomerates: crystallization features of chiral halogen and cyano monosubstituted phenyl glycerol ethers

All ortho-substituted Cl, Br, I, and CN phenyl glycerol ethers crystallize as racemic conglomerates, whereas meta- and para-derivatives constitute racemic compounds in the solid state. Only meta-halogen-substituted phenyl glycerol ethers, alongside the thermodynamically preferential heterochiral racemic compound phase, reveal the simultaneous existence of a conglomerate phase; the last state is metastable and turns into a stable racemic compound just in the crystalline phase.     

Chiral para-alkyl phenyl ethers of glycerol: synthesis and testing of chirality driven crystallization,liquid crystal,and gelating properties

A series of enantiopure and racemic p-alkylphenyl glycerol ethers 1a–k were synthesized. A new, sensitive, and pictorial method of comparison of the IR spectra of solid enantiopure and racemic samples was developed to obtain preliminary information on the crystallization types of these compounds. In order to detect the subtle differences in the organization of the chiral solid phase, a new easily implemented approach, based on a chromatographic measuring of the relative abundance of the enantiomers in a single solution in equilibrium with a solid sample of arbitrary (0 < ee < 1) composition, is reported. One new conglomerate compound (Alk = n-Pr) and one borderline case (Alk = n-Bu) are disclosed. Higher members of the series of 1 (starting with an n-Bu derivative) are turned into liquid crystals upon melting; no significant differences between racemic and non-racemic samples were found. Only enantiopure methyl-, n-butyl, n-pentyl, n-hexyl, and n-heptyl substituted 1 were able to form supramolecular gels in hydrocarbon solvents; all racemic ethers 1 did not show such ability.