Gold-Catalyzed Michael-Type Reactions and [4 + 2]-Annulations between Propiolates and 1,2-Benzisoxazoles with Ester-Directed Chemoselectivity
作者:Yashwant Bhaskar Pandit、Rajkumar Lalji Sahani、Rai-Shung Liu
DOI:10.1021/acs.orglett.8b02663
日期:2018.11.2
This work reports gold-catalyzed reactions between 1,2-benzisoxazoles and propiolate derivatives with ester-controlled chemoselectivity. For ethyl propiolates 1′, their gold-catalyzed reactions afforded Michael-type products 4, whereas tert-butyl propiolates 1 preferably underwent [4 + 2]-annulations, further yielding 6H-1,3-oxazin-6-one derivatives 3.
这项工作报告了1,2-苯并恶唑与丙酸酯衍生物之间的金催化反应,并具有酯控制的化学选择性。对于丙酸乙酯1',其金催化的反应得到迈克尔型产物4,而丙酸叔丁酯1优选经历[4 + 2]环化,进一步产生6 H -1,3-恶嗪-6-一衍生物3。
An efficient synthesis of oxazolines <i>via</i> a cascade reaction between azaoxyallyl cations and 1,2-benzisoxazoles
作者:Li Sun、Yi Liu、Yankai Wang、Yuanyuan Li、Zhiwen Liu、Tao Lu、Wenhai Li
DOI:10.1039/c9ob01366k
日期:——
A formal [3 + 2] cycloaddition reactionbetween the C and O terminals of azaoxyallyl cations formed in situ and 1,2-benzisoxazoles has been realized. This one-pot cycloaddition method provided an effective and practical pathway to synthesize oxazoline in good yields under mild conditions. The title products exhibited unique fluorescence properties.
[3 + 2]-Cycloaddition of Azaoxyallyl Cations with 1,2-Benzisoxazoles: A Rapid Entry to Oxazolines
作者:Juan Feng、Ming Zhao、Xuanzi Lin
DOI:10.1021/acs.joc.9b01166
日期:2019.8.2
novel and efficient [3 + 2] cycloaddition reaction of azaoxyallyl cations and 1,2-benzisoxazoles to give oxazoline derivatives has been developed. The transformation provides a rapid entry to functionalized oxazoline scaffolds under mild and transition-metal-free conditions, which will greatly expand the reaction types of heterocycle chemistry and pave the way for syntheses of bioactivecompounds.
Intermolecular Interception of α-Oxo Gold Carbenes of Nitroalkyne Cycloisomerization with 1,2-Benzo[<i>d</i>]isoxazole: Synthesis of Functionalized Quinazoline 1-Oxides
作者:Pawan S. Dhote、Kishor A. Pund、Chepuri V. Ramana
DOI:10.1021/acs.joc.1c01221
日期:2021.8.6
The known nitrogen-transfer reagent 1,2-benzo[d]isoxazole has been used to trap the postulated α-oxo gold carbene intermediate involved in the [Au]-catalyzed internal redox process of 2-alkynylnitrobenzenes. This process led us to develop a general convergent method for the synthesis of highlyfunctionalized quinazoline 1-oxides.