The asymmetric organocatalytic 1,3-dipolar cycloaddition of alkyl pyruvate-derived nitrones and α,β-unsaturated aldehydes
作者:Łukasz Weseliński、Eleonora Kalinowska、Janusz Jurczak
DOI:10.1016/j.tetasy.2012.02.003
日期:2012.2
catalytic asymmetric 1,3-dipolar cycloaddition of pyruvate-derived nitrones to α,β-unsaturated aldehydes was investigated in the presence of various chiral amines. Highly functionalized isoxazolidines containing a quaternary stereocenter were obtained in moderate yields with up to 92% ee. To the best of our knowledge, this is the first example of an enantioselective 1,3-dipolar cycloaddition of ketonitrones
在各种手性胺的存在下,研究了丙酮酸衍生的硝酮与α,β-不饱和醛的催化不对称1,3-偶极环加成反应。以中等收率获得了具有季立体中心的高度官能化的异恶唑烷,ee最高可达92%。据我们所知,这是酮硝酮对映选择性1,3-偶极环加成的第一个例子。随后分两步将模型产物转化为2-吡咯烷酮衍生物。