METHOD FOR PRODUCING AN ARENE WITH AN AROMATIC C-N BOND ORTHO TO AN AROMATIC C-O BOND
申请人:THE ROYAL INSTITUTION FOR THE ADVANCEMENT OF LEARNING/MCGILL UNIVERSITY
公开号:US20170066711A1
公开(公告)日:2017-03-09
A method for producing an arene with an aromatic C—N bond ortho to an aromatic C—O bond from a hydroxy arene comprising said aromatic C—O bond is provided. This method comprising the steps a) ortho-oxygenating the hydroxy arene to produce an ortho-quinone, b) condensating the ortho-quinone with a nitrogen nucleophile to generate a compound of Formula (IVa) or (IVb), and c) allowing 1,5-hydrogen atom shift of the compound of Formula (IVa) or (IVb), thereby producing arenes with a C—N bond ortho to a C—O bond of Formula (Va) and (Vb), respectively:
acids toward benzoxazin-2-ones synthesisunder mild conditions was developed. This hypervalentiodine(III)-promoted process eliminated the use of a metal catalyst or additive with high levels of functional group tolerance. Hypervalentiodine(III) was both an oxidant and a radical initiator for this reaction. The synthetic utility of this method was confirmed by the synthesis of the natural product cephalandole
开发了一种新的催化剂自由基氧化 C-H 环化芳胺与 α-酮酸在温和条件下合成苯并恶嗪-2-酮的反应。这种高价碘 (III) 促进的过程消除了使用具有高水平官能团耐受性的金属催化剂或添加剂。高价碘 (III) 既是该反应的氧化剂又是自由基引发剂。该方法的合成效用通过天然产物头孢菌素 A 的合成得到证实。
Visible-light-induced C(sp<sup>3</sup>)–H activation for a C–C bond forming reaction of 3,4-dihydroquinoxalin-2(1<i>H</i>)-one with nucleophiles using oxygen with a photoredox catalyst or under catalyst-free conditions
作者:Pavan Sudheer Akula、Bor-Cherng Hong、Gene-Hsiang Lee
DOI:10.1039/c8ra03259a
日期:——
A convenient photocatalyzed oxidative coupling reaction of 4-alkyl-3,4-dihydroquinoxalin-2(1H)-one and its derivatives with a variety of nucleophiles was developed with a ruthenium photoredox catalyst and oxygen under a household compact fluorescent light. With a slower reaction rate, the cross coupling transformation can be achieved in the absence of an external photocatalyst with a similar isolated
在家用紧凑型荧光灯下,采用钌光氧化还原催化剂和氧气,开发了4-烷基-3,4-二氢喹喔啉-2(1 H )-酮及其衍生物与多种亲核试剂的便捷光催化氧化偶联反应。通过较慢的反应速率,可以在没有外部光催化剂的情况下实现交叉偶联转化,并具有相似的分离产率。还展示了天然产物头孢烯醇 A 的合成应用。
Unexpected TFA-catalyzed tandem reaction of benzo[d]oxazoles with 2-oxo-2-arylacetic acids: synthesis of 3-aryl-2H-benzo[b][1,4]oxazin-2-ones and cephalandole A
TFA-catalyzed reaction of benzo[d]oxazoles with 2-oxo-2-arylacetic acids: synthesis of 3-aryl-2H-benzo[b][1,4]oxazin-2-ones and the natural product cephalandole A.
“On water” ultrasound-assisted one pot efficient synthesis of functionalized 2-oxo-benzo[1,4]oxazines: First application to the synthesis of anticancer indole alkaloid, Cephalandole A
作者:Pradeep K. Jaiswal、Vashundhra Sharma、Jaroslav Prikhodko、Irina V. Mashevskaya、Sandeep Chaudhary
DOI:10.1016/j.tetlet.2017.03.048
日期:2017.5
For the first time, an efficient, simple, synthetic green protocol for the one-pot synthesis of functionalized 2-oxo-benzo[1,4]oxazines 24–29 in water under ultrasound irradiation is presented. As compared to conventional methods, the present protocol avoids traditional chromatography and purification steps and furnished the target molecules in excellent yields (upto 98%) with no side products. The