已测试了一系列环状硝酮在增强的苯乙烯自旋捕获聚合反应和硝酮介导的自由基偶联反应中的自旋捕获活性。发现rac -2-异丙基-2,3-二甲基-1-氧基-2,3-二氢-咪唑-4-酮是最有效的硝酮。确定该腈的特定聚苯乙烯大自由基加成率为8.0×10 3 L mol –1 s –1,这比以前研究的化合物高10倍。通过增强的自旋捕获聚合,低聚物范围为30000 g mol –1的聚合物获得了。观察到分子量对单体转化的强烈依赖性,这可以由高捕获率来解释。在硝酮介导的自由基偶联中,获得了溴官能聚合物的几乎理想的偶联,并证实了残余烷氧基胺官能团的成功引入。
Original conformationally restricted C‐glycosyl amino acid derivatives in different series have been isolated following a two‐step strategy involving 1,3‐dipolar cycloaddition between l‐(–)‐menthone‐derived nitrone and C‐vinylglycosides as the key step. The cycloaddition reaction was highly regio‐ and stereoselective leading to corresponding cycloadducts in high yield. Simple cleavage of the chiral auxiliary