Metal free regio - and stereoselective semireduction of CF3-substituted N-allenamides
Clément Gommenginger1, Maxime Hourtoule1, Marco Menghini1
1Equipe Synthèse Organique et Phytochimie, Institut de Chimie, CNRS-UdS, UMR 7177, 4 rue Blaise Pascal, CS 90032, 67081 Strasbourg, France. lmiesch@unistra.fr.
Abstract:
We developed a chemoselective metal-free access for the 1,2- and 2,3-semireduction of CF3-N-allenamides. The enamide functionality of CF3-substituted N-allenamides could be efficiently reduced by Et3SiH/BF3·OEt2 in total regioselectivity and good stereoselectivity, whereas DBU promoted the isomerization of the resulting allyl amide leading exclusively to the E-configurated enamide.
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