Iron role in the electrochemical cyclopropanation reaction of activated olefins and halogenated compounds |
| |
| Authors: | Rogé rio T. Ribeiro,Ivanildo L. de Mattos,Sté phane Sengmany,Rachid Barhdadi,Eric Lé onel,Christine Cachet-Vivier,Marcelo Navarro |
| |
| Affiliation: | aDepartamento de Química Fundamental, Universidade Federal de Pernambuco, Av. Prof. Luiz Freire, s/n, Cid. Universitária, Recife – PE, 50740-540, Brazil;bDepartamento de Quimica de Los Materiales, Faculdad de Química y Biología, Universidad de Santiago de Chile, Av. Lib. Bernardo O’Higgins 3363, 917-009, Santiago, Chile;cEquipe Electrochimie et Synthèse Organique, Institut de Chimie et des Matériaux Paris-Est UMR 7182 CNRS-Université Paris Est-Créteil, 2 rue H. Dunant, 94320, Thiais, France |
| |
| Abstract: | The electrochemical procedure for cyclopropanation reaction between benzal chloride (BC) and dimethyl itaconate (DMI), using Cu(I) salt, iron rod as sacrificial anode, and low temperature (−10 °C < T < −5 °C), was investigated by cyclic voltammetry and electrolysis. The variation of the experimental parameters of electrolyses, such as the absence or the presence of CuBr during the pre-electrolysis step, or its substitution by an initial amount of iron salt (FeCl2, FeBr2 or FeI2), and pyridine addition to the reaction medium showed that the presence of dissociated Fe(II) is essential to the cyclopropanation process. The Cu(I) salt is deposited on the cathode surface during the pre-electrolysis, providing the accumulation of Fe(II) in solution, which does not act as catalyst in the electrochemical process. The best cyclopropanation yield (81%) was reached in DMF/pyridine (9:1) in the presence of FeI2 salt. A cyclopropanation mechanism involving two possible pathways was suggested, implying both an anionic and a radical BC intermediates. |
| |
| Keywords: | Electrochemical cyclopropanation Iron Benzal chloride Dimethyl itaconate Mechanism |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
