Nouvelles Réactions d'Allylation Radicalaire : Exploitation de la Rupture homolytique de Liaisons Carbone-Oxygène et Carbone-Carbone

摘要

This PhD thesis is divided in eight chapters. The first three bibliographic chapters present the general principles of radical chemistry, the possibility offered by the xanthate radical chemistry and a review of the radical allylation methods, main focus of this work. The three next chapters are dedicated to the exploitation of the radical allylation of allylic alcohols, recently discovered in our laboratory. The use of such a technology enabled the preparation of functionalized enol ethers, ketones and 1,4-diketones, vinylsulfides, and finally fluoro- and trifluoromethyl-alkenes. The obtained 1,4-diketones and vinylsulfides have in particular been utilized to prepare functionalized carbo- and hetero-cycles. A remarkable manifestation of polar effects in the radical fragmentation process has then been discovered in the course of our study towards the synthesis of trifluoromethyl-alkenes. This effect has allowed for the development of a new ketone and 1,5-diketone synthesis featuring a rare carbon-carbon bond homolytic cleavage. Our results are presented in a 7th chapter. Last but not least, a new synthetic route to alpha-keto vinyl carbinols, a class of compound with high synthetic potential, has been devised. This method exploits the Mislow-Braverman-Evans sigmatropic rearrangement of allylic sulfoxides. Our synthesis uses simple ketones as starting material and represents the most straightforward synthetic path to alpha-keto vinyl carbinols reported to date.