General Synthesis of Tri-Carbo-Substituted <i>N</i><sup>2</sup>-Aryl-1,2,3-triazoles <i>via</i> Cu-Catalyzed Annulation of Azirines with Aryldiazonium Salts
作者:Fang-Fang Feng、Jun-Kuan Li、Xuan-Yu Liu、Fa-Guang Zhang、Chi Wai Cheung、Jun-An Ma
DOI:10.1021/acs.joc.0c01433
日期:2020.8.21
The general synthesis of fully substituted N2-aryl-1,2,3-triazoles is hitherto challenging compared with that of the N1-aryl counterparts. Herein, we describe a Cu-catalyzed annulation reaction of azirines and aryldiazonium salts. This regiospecific method allows access to a broad spectrum of tri-carbo N2-aryl-1,2,3-triazoles substituted with diverse aryl and alkyl moieties. Its utility is highlighted
Comparison of the Photochemistry of 3-Methyl-2-phenyl-2<i>H</i>-azirine and 2-Methyl-3-phenyl-2<i>H</i>-azirine
作者:Xiaoming Zhang、Sujan K. Sarkar、Geethika K. Weragoda、Sridhar Rajam、Bruce S. Ault、Anna D. Gudmundsdottir
DOI:10.1021/jo402443w
日期:2014.1.17
acetonitrile yields heterocycles 6 and 7. Laser flash photolysis of 1b in acetonitrile shows a transient absorption with a maximum at 320 nm due to the formation of ylide 8, which has a lifetime on the order of several milliseconds. Similarly, photolysis of 1b in cryogenic argon matrixes results in ylide 8. Density functional theory calculations were performed to support the proposed mechanism for the photoreactivity
A modular 2H-azirine synthesis from ketoximeacetates via Cs2CO3-mediated cyclization has been developed. The reaction utilizes easily available starting materials and provides a general synthetic route to 2,3-diaryl-2H-azirines in good to excellent yields under mild conditions, which is complementary to the conventional approaches for the synthesis of 2H-azirines. A gram-scale reaction was performed
已经开发了由乙酸酮肟通过Cs 2 CO 3介导的环化合成的模块化2 H-叠氮基。该反应利用容易获得的原料,并在温和条件下以良好至优异的产率提供了合成2,3-二芳基-2 H-叠氮基的一般合成路线,这是合成2 H-叠氮基的常规方法的补充。进行了克级反应以证明该合成方法的放大适用性。重要的是,2 H-叠氮基可以有效地转化为各种氮杂杂环。
Visible-Light-Induced Formal [3+2] Cycloaddition for Pyrrole Synthesis under Metal-Free Conditions
A photocatalytic formal [3+2] cycloaddition of 2H‐azirines with alkynes has been achieved under irradiation by visiblelight in the presence of organic dye photocatalysts. This transformation provides efficient access to highly functionalized pyrroles in good yields and has been applied to the synthesis of drug analogues. A primary trial of photocascade catalysis merging energy transfer and redox neutral
在有机染料光催化剂的存在下,在可见光照射下,已实现了2 H H叠氮基与炔烃的光催化形式[3 + 2]环加成反应。这种转化提供了以高收率高效获得高度官能化吡咯的途径,并已应用于药物类似物的合成。光级联催化合并能量转移和氧化还原中性反应的初步试验显示是成功的。
Kinetic Resolution of 2<i>H</i>-Azirines by Asymmetric Imine Amidation
of a chiral N,N′‐dioxide/ScIII complex, thus providing a promising method to obtain the enantioenriched 2H‐azirine derivatives and protecting‐group free aziridines at the same time. It is rare to find an example of N1 of an oxindole participating in a reaction over C3. Moreover, chiral 2H‐azirines were stereospecifically transformed into an unprotected aziridine and α‐amino ketone.