185739-14-4Relevant articles and documents
Experimental and Theoretical Studies on Rhodium-Catalyzed Coupling of Benzamides with 2,2-Difluorovinyl Tosylate: Diverse Synthesis of Fluorinated Heterocycles
Wu, Jia-Qiang,Zhang, Shang-Shi,Gao, Hui,Qi, Zisong,Zhou, Chu-Jun,Ji, Wei-Wei,Liu, Yao,Chen, Yunyun,Li, Qingjiang,Li, Xingwei,Wang, Honggen
, p. 3537 - 3545 (2017)
Fluorinated heterocycles play an important role in pharmaceutical and agrochemical industries. Herein, we report on the synthesis of four types of fluorinated heterocycles via rhodium(III)-catalyzed C-H activation of arenes/alkenes and versatile coupling with 2,2-difluorovinyl tosylate. With N-OMe benzamide being a directing group (DG), the reaction delivered a monofluorinated alkene with the retention of the tosylate functionality. Subsequent one-pot acid treatment allowed the efficient synthesis of 4-fluoroisoquinolin-1(2H)-ones and 5-fluoropyridin-2(1H)-ones. When N-OPiv benzamides were used, however, [4 + 2] cyclization occurred to provide gem-difluorinated dihydroisoquinolin-1(2H)-ones. Synthetic applications have been demonstrated and the ready availability of both the arene and the coupling partner highlighted the synthetic potentials of these protocols. Mechanistically, these two processes share a common process involving N-H deprotonation, C-H activation, and olefin insertion to form a 7-membered rhodacycle. Thereafter, different reaction pathways featuring β-F elimination and C-N bond formation are followed on the basis of density functional theory (DFT) studies. These two pathways are DG-dependent and led to the open chain and cyclization products, respectively. The mechanistic rationale was supported by detailed DFT studies. In particular, the origins of the intriguing selectivity in the competing β-F elimination versus C-N bond formation were elucidated. It was found that β-F elimination is a facile event and proceeds via a syn-coplanar transition state with a low energy barrier. The C-N bond formation proceeds via a facile migratory insertion of the Rh-C(alkyl) into the Rh(V) amido species. In both reactions, the migratory insertion of the alkene is turnover-limiting, which stays in good agreement with the experimental studies.
6-HETEROARYLOXY BENZIMIDAZOLES AND AZABENZIMIDAZOLES AS JAK2 INHIBITORS
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Paragraph 0922; 0923, (2021/11/13)
The present disclosure provides 6-heteroaryloxy benzimidazole and azabenzimidazole compounds and compositions thereof useful for inhibiting JAK2.
DIHYDROPYRIMIDINE COMPOUND AND PREPARATION METHOD AND USE THEREOF
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Paragraph 0139; 0140, (2019/07/18)
The present invention relates to a dihydropyrimidine compound having an antiviral activity, a pharmaceutical composition comprising same, a preparation method therefor and the uses thereof in the prevention or treatment of viral diseases including, but no
Neighboring phenolic group-activated: Gem -difluoroallylboration of imines for the catalyst-free synthesis of gem -difluorohomoallylamines
Yang, Xing,Zhang, Feng,Zhou, Yang,Huang, Yi-Yong
supporting information, p. 3367 - 3371 (2018/05/23)
We herein report an unprecedented addition reaction of pinacol gem-difluoroallylborates and imines enabled by a neighboring phenolic group in an N-protecting group under catalyst-free conditions, thus facilitating the construction of a wide range of racemic gem-difluorohomoallylamine derivatives. Based on the control experiments, a plausible transition state via the Zimmerman-Traxler model was proposed to elucidate the significance of the neighboring phenolic group, as well as the γ-selectivity of the boronate reagents.
