Yves Tondeur

Organomentallic compounds : LXIII. Synthesis, optical stability, stereo-selective and -specific reactions of chiral triorganotin hydrides☆

Optically active triorganotin hydrides have been synthesized by asymmetric reduction of the corresponding halides. These optically stable compounds undergo stereoselective conversions into other optically stable compounds such as tetraorganotin compounds (by reaction with diazomethane or with bifluorenylidene) or hexaorganoditin compounds (by reaction in the presence of palladium) or into optically unstable compounds such as methylneophylphenyltin chloride (by reaction with CCl4). The HD exchange between optically active methylneophylphenyltin hydride (deuteride) and triphenyltin deuteride (hydride) occurs with retention of configuration at the metal atom.

Synthesis and optical stability of chiral triorganotin hydrides

Abstract The first optically-active triorganotin hydrides are reported viz.: (+)−and ()-methylneophylphenyltin hydride and ()-t-butylneophylphenyltin hydride; they are fairly optically stable.

Stereoselective transformations of the optically-active trioganotin hydrides into optically-active tetraorganotin compounds

Abstract (−)-t-Butylneophylphenyltin hydride reacts with diazomethane to give (−)-t-butylmethylneophylphenyltin, while (−)- or (+)-methylneophylphenyltin hydrides add to the double bond of bifluorenylidene to give (−)- or (+)-bifluorenylylmethylneophylphenyltin, respectively

Organometallic compounds : LXXII. Reactions of racemic tetraorganotin compounds with butyllithium and with lithium aluminum hydride

Abstract Racemic methylneophylptrityltin (I) reacts with an excess of butyllithium to give dibutylmethylneophyltin (II) in high yield, whereas bifluorenyl-9-ylmethylneophenyltin is converted with an excess butyllithium into butylmethylneophylphenyltin (III) together with some (II). This shows that the phenyl is cleaved off as easily as the trityl group but less than the bifluororenylyl group. Methylphenyl(phenylethynyl)(2-phenylpropyl)tin and phenylethynyltrimethyltin react with LiAlH 4 ; the phenylethynyl—tin bond is cleaved but the formed phenylacetylene and organotin hydride react together to give the expected adduct. Bifluorenyl-9-ylmethylneophylphenyltin is converted with LiAlH 4 , into 1,2-dimethyl-1,2-dineophyl-1,2-diphenylditin.

The methyldiazonium ion in water: competition between hydrolysis and proton exchange

The methyldiazonium ion, generated from four different precursors, was found to undergo proton exchange with deuteriated phosphate buffer solutions.

Synthesis of the first example of an optically active hexaorganoditin

The first example of an optically active hexaorganoditin has been synthesized by the stereoselective reaction of the corresponding triorganotin hydride in the presence of palladium.