Cu(OTf)2介导的S N 2型亲核开环的高效策略,然后进行许多2-芳基-N-甲苯磺酰氮杂环丁烷与腈的[4 + 2]环加成反应,从而得到各种取代的四氢嘧啶据报道产量极高。所得的四氢嘧啶可通过酸催化的水解容易地转化为合成上重要的1,3-二胺。该策略已扩展到由对映纯二取代的氮杂环丁烷合成对映体纯的四氢嘧啶。反应通过我们之前提出的S N 2型机理进行。
2-Aryl-<i>N</i>-tosylazetidines as Formal 1,4-Dipoles for [4 + 2] Cycloaddition Reactions with Nitriles: An Easy Access to the Tetrahydropyrimidine Derivatives
作者:B. A. Bhanu Prasad、Alakesh Bisai、Vinod K. Singh
DOI:10.1021/ol048161l
日期:2004.12.1
[Graphics]A new synthetic route to 2-aryl-N-tosyl azetidines has been developed starting from N-tosylarylaldimines in two steps in an overall yield of 63-70%. A formal [4 + 2] cycloaddition of these 2-aryl-N-tosylazetidines with nitriles in the presence of BF3.OEt2 has been described for the synthesis of substituted tetrahydropyrimidines. It is proposed that the reaction proceeds in Ritter fashion.