Department of Chemistry, Washington University, St. Louis, Missouri 63130, USA.
Org Lett. 2010 Apr 16;12(8):1720-3. doi: 10.1021/ol100317t.
A competition experiment was designed so that the relative rates of anodic cyclization reactions under various electrolysis conditions can be determined. Reactions with ketene dithioacetal and enol ether-based substrates that use lithium methoxide as a base were shown to proceed through radical cation intermediates that were trapped by a sulfonamide anion. Results for the oxidative coupling of a vinyl sulfide with a sulfonamide anion using the same conditions were consistent with the reaction proceeding through a nitrogen-radical.
设计了一个竞争实验,以确定在各种电解条件下阳极环化反应的相对速率。使用甲醇锂作为碱的偕二硫缩醛和烯醇醚基底物的反应被证明是通过自由基阳离子中间体进行的,这些中间体被磺酰胺阴离子捕获。使用相同条件下的乙烯基硫醚与磺酰胺阴离子的氧化偶联的结果与通过氮自由基进行的反应一致。