A General and Straightforward Method for the Synthesis of 2-Trifluoromethylbenzothiazoles
摘要:
An efficient one-pot method for the synthesis of 2-trifluoromethylbenzothiazoles by the treatment of trifluoromethylimidoyl chlorides with sodium hydrosulfide hydrate using PdCl(2) as the sole catalyst in DMSO is described. The reaction proceeds via thiolation/C H bond functionalization/C S bond formation in moderate to high yields with good functional group tolerance.
在本文中,我们研究了尿嘧啶和酞嗪与N-(芳基)-2,2,2-三氟乙亚胺基氯衍生物的反应。结果表明,当亚氨基酰氯衍生物在邻位(3a–c)处具有氟原子时,在S N i机理下分两步,然后在S N Ar反应机理下生成ayl-5-(三氟甲基)-1H-苯并[e] ] [1,2,4]三唑[1,2-a] [1,2,4]三嗪-1,3(2H)-二酮(4a–c)和6-(三氟甲基)苯并[5,6] [1,2,4]三嗪并[1,2-b]酞嗪-8,13-二酮(4i,4j)的产率高至优异。在其他亚胺基衍生物(3d–h和3i,3j)在这些条件下不会发生环化反应,因此会产生1-芳基-2,2,2-三氟甲基)-4-苯基-1,2,4-三唑烷-3,5-二酮(4d–h)和2- (2,2,2-三氟-1-(芳基)乙基)-2,3-二氢酞嗪-1,4-二酮(4k,4l)(非环状产物),收率良好。
nm with moderate to good fluorescence quantum yields. These compounds also showed high Stokes shifts, and can be used to develop ultrasensitive fluorescent molecular probes to study a variety of biological events and processes.
A metal‐free approach for the synthesis of 5‐trifluoromethyl‐1,2,4‐triazoles from trifluoroacetimidoyl chlorides and hydrazones has been achieved under aerobic oxidative conditions. The reaction proceeds through a cascade base‐promoted intermolecular C−N bond formation and iodine‐mediated intramolecular C−N bond oxidative coupling sequence. The protocol features broad substrate scope and can be scaled
Cu-catalyzed tandem reactions of fluorinated alkynes with sulfonyl azides en route to 2-trifluoromethylquinolines
作者:Yajun Li、Lisi Zhang、Li Zhang、Yongming Wu、Yuefa Gong
DOI:10.1039/c3ob41658e
日期:——
A novel method for the synthesis of 2-trifluoromethylquinolines via Cu-catalyzed tandem reactions was reported. A strong electronic effect was observed, but the steric effect was negligible.
e annulation reaction for the efficient construction of 2-(trifluoromethyl)quinazolin-4(3H)-ones has been developed. This transformation employs readily available isatins and trifluoroacetimidoyl chlorides as the starting materials, providing a facile and practical route to diverse biologically relevant quinazolin-4(3H)-one derivatives. A plausible reaction pathway has been proposed based on the mechanistic
metal-free approach for the synthesis of 5-trifluoromethyl-1,2,4-triazoles via I2-mediated [4+1] annulation of readily available trifluoroacetimidohydrazides and methyl ketones has been achieved. The transformation involves iodination/Kornblum oxidation, intermolecular dehydration condensation and an iodine-mediated intramolecular cyclization/aromatization sequence. The developed protocol can be easily scaled
已经实现了一种通过 I 2介导的 [4+1] 环化容易获得的三氟乙酰氨基酰肼和甲基酮来合成 5-三氟甲基-1,2,4-三唑的无金属方法。该转化包括碘化/Kornblum 氧化、分子间脱水缩合和碘介导的分子内环化/芳香化序列。开发的协议可以很容易地扩展到 3 mmol 规模而不会明显降低效率,并且可以通过连续的一锅方式实施。