Synthesis of 3-Aza-bicyclo[3.1.0]hexan-2-one Derivatives via Gold-Catalyzed Oxidative Cyclopropanation of <i>N</i>-Allylynamides
作者:Kai-Bing Wang、Rui-Qiao Ran、Shi-Dong Xiu、Chuan-Ying Li
DOI:10.1021/ol4007629
日期:2013.5.17
N-Allylynamides with various functional groups and different substitution patterns can be converted into 3-aza-bicyclo[3.1.0]hexan-2-one derivatives in moderate to high yield using IMesAuCl/AgBF4 as the catalyst and pyridine N-oxide as the oxidant. A noncarbene mediated approach is proposed as the mechanism.
Efficient and Flexible Synthesis of Highly Functionalised 4‐Aminooxazoles by a Gold‐Catalysed Intermolecular Formal [3+2] Dipolar Cycloaddition
作者:Andrew D. Gillie、Raju Jannapu Reddy、Paul W. Davies
DOI:10.1002/adsc.201500905
日期:2016.1.21
fully substituted and functionalised 4‐aminooxazoles are accessed by an efficient intermolecular reaction between an ynamide and an N‐acylpyridinium N‐aminide in the presence of a gold catalyst. The formal [3+2] dipolar cycloaddition employs a nucleophilic nitrenoid approach to access the 1,3‐N,O‐dipole character in a controllable fashion. The selectivity for a cycloaddition pathway provides a stark
Selenium-π-Acid Catalyzed Oxidative Functionalization of Alkynes: Facile Access to Ynones and Multisubstituted Oxazoles
作者:Lihao Liao、Hang Zhang、Xiaodan Zhao
DOI:10.1021/acscatal.8b01595
日期:2018.7.6
Unprecedented selenium-catalyzed propargylic oxidation of alkynes is disclosed. Various propargylphosphonates and 3-alkynoates were efficiently converted to valuable ynones via unusual C–C triple bond migration and deselenenylation at a vinyl carbon. By the strategies of tautomerization of enamine intermediate and SN2 displacement, similar conditions were effective for the oxidative difunctionalization
公开了前所未有的硒催化炔烃的炔丙基氧化。各种炔丙基膦酸酯和3-链烷酸酯通过不寻常的CC三键迁移和乙烯基碳上的硒烯基化反应,有效地转化为有价值的炔酮。通过烯胺中间体的互变异构和S N 2置换的策略,相似的条件对于乙酰胺的氧化双官能化有效,从而提供了具有高区域选择性的多取代恶唑。机理研究揭示了这些详细的过程。
<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 rearrangementsthermally. 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 sigmatropicrearrangements, leading to vinyl imidate formation. Collectively
Gold-Catalyzed Nitrene Transfer from Benzofuroxans to <i>N</i>-Allylynamides: Synthesis of 3-Azabicyclo[3.1.0]hexanes
作者:Nikolay V. Shcherbakov、Dmitry V. Dar’in、Vadim Yu. Kukushkin、Alexey Yu. Dubovtsev
DOI:10.1021/acs.joc.1c01654
日期:2021.9.17
The gold-catalyzed reaction between benzofuroxans, functioning as nitrene transfer reagents, and N-allylynamides leads to 3-azabicyclo[3.1.0]hexan-2-imines. This highly selective annulation proceeds smoothly under mild conditions (5 mol % Ph3PAuNTf2, PhCl, 60 °C) and exhibits high functional group tolerance (21 examples, ≤96% yields). The obtained cyclopropanated products represent a useful synthetic