Solvent attack in Grignard reagent formation from bromocyclopropane and 1-bromohexane in diethyl ether
作者:John F. Garst、Ferenc Ungvary、Rajnish Batlaw、Kathryn Easton Lawrence
DOI:10.1021/ja00014a034
日期:1991.7
In the reaction of magnesium with bromocyclopropane in diethyl ether at reflux, intermediate cyclopropyl radicals attack the solvent, giving cyclopropane (20-30 mol/100 mol of bromocyclopropane consumed) and solvent-derived products. In contrast, the similar reaction of 1-bromohexane gives no more than 0.5 mol of hexane from solvent attack by hexyl radicals. These data are consistent with calculations
在镁与溴环丙烷在乙醚中回流反应中,中间体环丙基自由基攻击溶剂,得到环丙烷(消耗 20-30 mol/100 mol 溴环丙烷)和溶剂衍生产物。相比之下,1-溴己烷的类似反应由于己基自由基的溶剂侵蚀产生不超过0.5mol的己烷。这些数据与基于具有自由扩散中间自由基的机制(D 模型)的计算一致,其中环丙基和己基在转化为格氏试剂时具有相似的反应性,但环丙基自由基对溶剂的反应性约为 1000 倍己基自由基