Scope and mechanism of the electrochemical Reformatsky reaction of α-haloesters on a graphite powder cathode in aqueous anolyte
作者:Carlos A. de Souza、Marcelo Navarro、Lothar W. Bieber、Madalena C.C. Areias
DOI:10.1016/j.electacta.2014.03.118
日期:2014.6
carbonyl compounds were submitted to electrochemical coupling on a graphite powder cathode using aqueous anolyte free of organic solvents. Preparative yields of coupling products could be obtained with ethyl 2-bromoisobutyrate and aromatic aldehydes. Ethyl 2-bromopropionate was much less efficient. Extensive variation of applied potential, electrolyte composition, stoichiometry, catalyst, leaving halogen
使用不含有机溶剂的水性阳极电解液,将六种α-卤代酸酯和十八种羰基化合物在石墨粉末阴极上进行电化学偶联。用2-溴异丁酸乙酯和芳族醛可以制得偶合产物。2-溴丙酸乙酯的效率低得多。施加的电势,电解质组成,化学计量,催化剂,在羰基化合物上留下卤素和活化取代基的广泛变化导致了这样的结论,即在大多数情况下,反应机理是通过卤化物还原产生的自由基中间体进行的。氯乙酸乙酯仅产生痕量的偶联产物,最可能是通过碳负离子机理产生的。