Iron(II)/copper(I)-mediated stereoselective carbozincation of ynamides. One-pot synthesis of alpha-allyl-tetrasubstituted-enamides

Hugo Lingua (1) , Francois Vibert (1) , Dominique Mouysset (1) , Didier Siri (1) , Michele P. Bertrand (1) , Laurence Feray (1)

1 ICR - Institut de Chimie Radicalaire

The iron(II) chloride- and copper(I) iodide-mediated carbozincation of a panel of substituted ynamides is described in this article. The reaction is totally regio- and stereoselective. Experiments showed that the reaction mediated with Fe(II) was more substrate dependent than the reaction performed with Cu(I). Interestingly, in the presence of allylbromide, stereoselective carboallylation can be achieved for the first time in a one-pot procedure, leading to skipped dienamides.

Keywords: aza-Claisen rearrangement; carbomagnesiation; carbometalation reactions; copper-catalyzed carbozincation; Copper (I) iodide; Dialkylzinc; reagents; stereocenters; terminal alkynes; Ynamides

Domains: Chemical Sciences; Organic chemistry

Hugo Lingua, Francois Vibert, Dominique Mouysset, Didier Siri, Michele P. Bertrand, et al.. Iron(II)/copper(I)-mediated stereoselective carbozincation of ynamides. One-pot synthesis of alpha-allyl-tetrasubstituted-enamides. Tetrahedron, 2017, 73 (25), pp.3415-3422. ⟨10.1016/j.tet.2017.04.065⟩. ⟨hal-01774256⟩