|
|||||
|
|
α,β-Unsaturated diesters: radical acceptors in dialkylzinc-mediated tandem radical addition/aldol condensation. A straightforward synthesis of rac-nephrosteranic acid |
|
| Authors: | Samantha Bazin Nicolas Vanthuyne Michèle P Bertrand |
| Institution: | a Laboratoire de Chimie Moléculaire Organique, UMR 6517, boite 562, Faculté des Sciences St Jérôme, Université Paul Cézanne, Av. Escadrille Normandie Niemen, 13397 Marseille Cedex 20, France b Laboratoire de Stéréochimie Dynamique et Chiralité, UMR 6180, Faculté des Sciences St Jérôme, Université Paul Cézanne, Av. Escadrille Normandie Niemen, 13397 Marseille Cedex 20, France c Laboratoire de Chimie Théorique et modélisation moléculaire, UMR 6517, Faculté des Sciences St Jérôme, Université de Provence, Av. Escadrille Normandie Niemen, 13397 Marseille Cedex 20, France |
| Abstract: | The sequence involving conjugate radical addition/aldol condensation/lactonization is a high yielding route to di- and tri-substituted γ-lactones starting from fumaric or maleic diesters. The reactions are mediated with dialkylzincs. The domino process relies on the ability of dialkylzinc to transform α-alkoxycarbonylalkyl radicals into zinc enolates. Compared to diethylzinc, dimethylzinc enables the use of a wider range of alkyl radical precursors. In addition, dimethylzinc is a convenient source of methyl radical, which leads to a straightforward synthesis of methylated derivatives related to α-methyl-paraconic acids. |
| Keywords: | Diethylzinc Dimethylzinc Radical-polar crossover reaction γ-Lactones Conjugate addition |
| 本文献已被 ScienceDirect 等数据库收录！ | |