NHC-catalyzed C–O or C–N bond formation: efficient approaches to α,β-unsaturated esters and amides
作者:Bo Zhang、Peng Feng、Yuxin Cui、Ning Jiao
DOI:10.1039/c2cc32862c
日期:——
Simple and efficient NHC-catalyzed transformations of bromoenal or α,β-dibromoenal into α,β-unsaturated esters or amides with high stereoselectivity through CâO or CâN bond formation have been demonstrated. The NHC-catalyzed processes occur under mild conditions. The ready availability of the starting materials, avoidance of external oxidants and the usefulness of the products all make the strategy attractive.
Rapid access to cinnamamides and piper amides <i>via</i> three component coupling of arylaldehydes, amines, and Meldrum's acid
作者:Santanu Ghosh、Chandan K. Jana
DOI:10.1039/c9gc02937k
日期:——
A practical method for the synthesis of cinnamamides and piper amides via a conceptually novel three component reaction of aldehydes, amines and Meldrum's acid has been reported. The reaction proceeds under operationally simple conditions without the aid of coupling reagents, oxidants, or catalysts, which are essential for the preparation of cinnamamides/piper amides via known methods. The formation
Oxidation of Aliphatic <font>α,β</font>-Unsaturated Aldimines to Amides Specifically by Oxone with AlCl<sub>3</sub>
作者:Zhou Lu、Lijun Peng、Wentao Wu、Longmin Wu
DOI:10.1080/00397910802138892
日期:2008.6.27
alpha,beta-Unsaturated aldimines were specifically oxidized to amides with Oxone in the presence of AlCl3 as a Lewis acid in CH2Cl2. No migration of aryl group occurred in the rearrangement reaction.
Convenient Synthesis of Substituted Piperidinones from α,β-Unsaturated Amides: Formal Synthesis of Deplancheine, Tacamonine, and Paroxetine
An intermolecular aza-double Michael reaction leading to functionalized piperidin-2-ones from simple starting materials has been developed. The method allows alpha,beta-unsaturated amides to be used as a synthon of the piperidine nucleus. In addition, the utility of this methodology is demonstrated by its application to a formal synthesis of the indolo[2,3-a]quinolizidine alkaloids, (+/-)-deplancheine, (+/-)-tacamonine, and the antidepressant paroxetine.