Nadia Pelloux-Léon

IN SEARCH FOR THIOKETENE S-OXIDE. A VINYL SULFOXIDE TO SULFINE REARRANGEMENT

Abstract Two approaches to thioketene S -oxide have been tested. This reactive heterocumulene was tentatively characterized by low temperature IR spectroscopy. In the course of this study, an unexpected vinyl sulfoxide to sulfine rearrangement was observed.

Thioacrolein S-oxide

Abstract Thioacrolein S -oxide was synthesized for the first time and characterized by low temperature NMR spectroscopy. Theoretical calculations about this unsaturated sulfine and two of its possible cyclic isomers were performed.

The rearrangement of α-imino-thioaldehydes into dihydro-1,3-thiazoles

Abstract α-Imino-thioaldehydes were generated by retro-Diels-Alder reaction under flash vacuum thermolysis conditions. They were found to be unstable and cyclized to 2,3-dihydro-1,3-thiazoles. This cyclization was investigated by ab initio calculations.

SYNTHESIS OF REACTIVE SULFINES BY FLASH VACUUM THERMOLYSIS : THIOFORMYL CYANIDE S-OXIDE AND THIOXOETHANAL S-OXIDE

Thioformyl cyanide S-oxide and thioxoethanal S-oxide were synthesized by retro Diels–Alder cleavage of their dimethylanthracene adducts under flash vacuum thermolysis conditions. They were characterized by low-temperature IR and NMR spectroscopy. The formation of thioformyl cyanide S-oxide was also confirmed by mass spectrometry.

Stereoselective synthesis of sulfinates from mannitol derived sulfites

Abstract The reaction of Grignard reagents with two mannitol derived sulfites has been studied. High diastereoselectivity (96% d.e.) was achieved with t -BuMgCl and a cyclohexylidene protected sulfite in THF in the presence of a Lewis acid.

New Reactions with Thioaldehydes and Thienium Cations

Abstract i) When generated under FVT conditions α-imino-thioaldehydes undergo a cyclization to dihydro-1,3-thiazoles. ii) Thienium cations, generated during a Pummerer reaction, can be trapped with dienes.