1297606-41-7Relevant academic research and scientific papers
Theoretical investigation of the reaction of dialkylzincs with α-alkoxycarbonyl radicals. Evaluation of α-bromoacrylates as radical acceptors in radical-polar crossover processes
Vibert, Fran?ois,Maury, Julien,Lingua, Hugo,Besson, Eric,Siri, Didier,Bertrand, Michèle P.,Feray, Laurence
, p. 8991 - 9002 (2015)
The evaluation of ethyl α-bromoacrylate as radical acceptor in dialkylzinc radical-polar cascades addresses the question of the parameters controlling homolytic substitution at zinc by α-alcoxycarbonyl radicals. Under non-degassed medium ethyl α-bromoacrylate reacts with diethylzinc to give a bromocyclopropane. The reaction involves successively radical addition, SH2 at zinc, conjugate addition of the resulting enolate to the electrophilic substrate and ring closure. Theoretical calculations were performed to get a better insight into the detailed mechanism. They highlight the impact of zinc(II) chelation on the formal SH2 step. Additional experiments performed in the presence of other electrophiles-aldehydes and acylsilanes-are discussed.
A convenient synthesis of (E)-α,β-unsaturated esters with total stereoselectivity promoted by catalytic samarium diiodide
Concellón, José M.,Rodríguez-Solla, Humberto,Concellón, Carmen,Díaz-Pardo, Ainhoa,Llavona, Ricardo
scheme or table, p. 262 - 264 (2011/03/21)
Synthesis of (E)-α,β-unsaturated esters in high yields and with total stereoselectivity is achieved from α-halo-β-hydroxy esters promoted by catalytic amounts of SmI2. The starting compounds were easily prepared from α-halo esters and aldehydes as a mixture of stereoisomers. A mechanism is proposed to explain this samarium(II)-promoted catalytic β-elimination reaction. Georg Thieme Verlag Stuttgart.
