在与α,β-不饱和亚胺鎓盐的形式氮杂-[3 + 3]环加成反应中作为潜在非环烯醇式酰胺的特曲那胺。一种意外的重排反应及一种合成取代哌啶的方法。

Tetronamides as latent acyclic vinylogous amides in formal aza-[3 + 3] cycloaddition reactions with alpha,beta-unsaturated iminium salts. An unexpected rearrangement and an approach to synthesis of substituted piperidines.

作者信息

Sydorenko Nadiya, Hsung Richard P, Darwish Ossama Saleh, Hahn Juliet M, Liu Jia

机构信息

Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA.

出版信息

J Org Chem. 2004 Oct 1;69(20):6732-8. doi: 10.1021/jo049108d.

DOI:10.1021/jo049108d

PMID:15387597

Abstract

A detailed account regarding formal aza-[3 + 3] cycloaddition reactions of tetronamides with alpha,beta-unsaturated iminium salts is described here. This investigation uncovers regioisomeric cycloadducts that were not found in previous studies involving this formal cycloaddition and an unexpected rearrangement that led to pyridines and dihydropyridines. Both stereochemical and regiochemical issues raised in this study provide further mechanistic insights into this cycloaddition. With careful control of reaction temperatures, the desired formal cycloadducts are obtained. Ensuing transformation of these cycloadducts into functionalized piperidines establishes the concept of employing tetronamides as latent acyclic vinylogous amides for the formal aza-[3 + 3] cycloaddition.

摘要

本文详细描述了特窗酸酰胺与α,β-不饱和亚胺鎓盐的形式氮杂-[3 + 3]环加成反应。该研究揭示了在先前涉及此形式环加成的研究中未发现的区域异构体环加合物以及导致吡啶和二氢吡啶的意外重排。本研究中提出的立体化学和区域化学问题为该环加成反应提供了进一步的机理见解。通过仔细控制反应温度，可获得所需的形式环加合物。将这些环加合物随后转化为功能化哌啶确立了将特窗酸酰胺用作形式氮杂-[3 + 3]环加成的潜在非环状乙烯型酰胺的概念。