<i>N-</i>Allyl-<i>N-</i>sulfonyl Ynamides as Synthetic Precursors to Amidines and Vinylogous Amidines. An Unexpected N-to-C 1,3-Sulfonyl Shift in Nitrile Synthesis
作者:Kyle A. DeKorver、Whitney L. Johnson、Yu Zhang、Richard P. Hsung、Huifang Dai、Jun Deng、Andrew G. Lohse、Yan-Shi Zhang
DOI:10.1021/jo200780x
日期:2011.6.17
N-allyl ynamides, which can also be accomplished thermally. An observation of N-to-C 1,3-sulfonyl shift was made when examining these aza-Claisen rearrangements thermally. This represents a useful approach to nitrile synthesis. While attempts to render this 1,3-sulfonyl shift stereoselective failed, we uncovered another set of tandem sigmatropic rearrangements, leading to vinyl imidate formation. Collectively
本文描述了从N-烯丙基-N-磺酰基炔酰胺合成脒的详细研究。从机理上讲,这是一个令人着迷的反应,由不同的途径组成,可能导致脱烯丙基化或烯丙基转移,具体取决于钯催化剂的氧化态、胺的亲核性和配体的性质。它本质上构成了 Pd(0) 催化的N-烯丙基炔酰胺的氮杂克莱森重排,该重排也可以通过热的方式完成。在热检查这些氮杂克莱森重排时观察到 N-to-C 1,3-磺酰基转移。这代表了一种有用的腈合成方法。虽然使这种 1,3-磺酰基移位立体选择性的尝试失败了,但我们发现了另一组串联 σ 重排,导致亚氨酸乙烯酯的形成。总的来说,这项工作展示了人们可以使用这些炔酰胺发现的丰富的化学反应。