New Optically Active -Butylarylthiophosphinic Acids and Their Selenium Analogues as the Potential Synthons of Supramolecular Organometallic Complexes: Syntheses and Crystallographic Structure Determination.

The aim of the research described in this publication is two-fold. The first is a detailed description of the synthesis of a series of compounds containing a stereogenic heteroatom, namely the optically active -stereogenic derivatives of -butylarylphoshinic acids bearing sulfur or selenium. The second is a detailed discussion dedicated to the determination of their structures by an X-ray analysis.

Nucleophilic Substitution at Tricoordinate Sulfur-Alkaline Hydrolysis of Optically Active Dialkoxysulfonium Salts: Stereochemistry, Mechanism and Reaction Energetics.

Optically active dialkoxyisopropylsulfonium salts were obtained by methylation (ethylation) of optically active alkyl isopropanesulfinates using methyl (ethyl) trifluoromethanesulfonate. Alkaline hydrolysis of a series of methoxy(alkoxy)sulfonium salts afforded the two sulfinate products methyl isopropanesulfinate and alkyl isopropanesulfinate, both formed with a slightly prevailing inversion of configuration at the sulfur atom. DFT calculations revealed that this substitution reaction proceeded stepwise according to an addition-elimination (A-E) mechanism involving the formation of high tetracoordinate S sulfurane intermediates.

Microbiologically Pure Cotton Fabrics Treated with Tetrabutylammonium OXONE as Mild Disinfection Agent.

The microbiological purity of textiles plays a pivotal role in the use of textiles, especially in hospitals and other medical facilities. Microbiological purity of cotton fabric was achieved by a new disinfection method using tetrabutyloammonium OXONE (TBA-OXONE) before washing. As a result of the disinfection, the cotton fabric became microbiologically pure, despite the markedly decreased washing time with respect to the widely used standard procedure.

Diastereoisomerically Pure, ()--1,2--isopropyli dene-(5--α-d-glucofuranosyl) -butanesulfinate: Synthesis, Crystal Structure, Absolute Configuration and Reactivity.

The reaction of -butylmagnesium chlorides with diastereomerically pure ()-1,2--isopropylidene-3,5--sulfinyl-α-d-glucofuranose ()- was found to be stopped at the stage of the corresponding, diastereoisomerically pure 1,2--isopropylidene-(5--α-d-glucofuranosyl) -butanesulfinate ()- for which the crystal structure and the ()-absolute configuration was determined by X-ray crystallography. Comparison of the absolute configurations of the starting sulfite ()-, and -butanesulfinate ()- (which crystallizes in the orthorhombic system, space group P222, with the single compound molecule present in the asymmetric unit), clearly indicates that the reaction of nucleophilic substitution at the stereogenic sulfur atom in the sulfite ()- occurs with the full inversion of configuration via the trigonal bipyramidal sulfurane intermediate in which both the entering and leaving groups are located in apical positions.

Acid catalyzed alcoholysis of sulfinamides: unusual stereochemistry, kinetics and a question of mechanism involving sulfurane intermediates and their pseudorotation.

The synthesis of optically active sulfinic acid esters has been accomplished by the acid catalyzed alcoholysis of optically active sulfinamides. Sulfinates are formed in this reaction with a full or predominant inversion of configuration at chiral sulfur or with predominant retention of configuration. The steric course of the reaction depends mainly on the size of the dialkylamido group in the sulfinamides and of the alcohols used as nucleophilic reagents.