Copper‐catalyzed one‐pot coupling reactions of aldehydes (ketones), tosylhydrazide and 2‐amino(benzo)thiazoles: An efficient strategy for the synthesis of
<i>N</i>
‐alkylated (benzo)thiazoles
作者:Zengyang Xie、Ruijiao Chen、Mingfang Ma、Lingdong Kong、Jun Liu、Cunde Wang
DOI:10.1002/aoc.5124
日期:2019.10
An efficient and practical C–N bond formation methodology for the synthesis of N‐alkylated (benzo)thiazoles was developed, via the copper‐catalyzed one‐pot two‐step reactions of 2‐amino(benzo)thiazoles and aldehydes (ketones) with tosylhydrazide. This cross‐coupling reaction proceeded smoothly and tolerated a broad range of functional groups (46 examples). A variety of functionalized N‐alkylated (benzo)thiazoles
Direct N-alkylation of amino-azoles with alcohols catalyzed by an iridium complex/base system
作者:Feng Li、Haixia Shan、Lin Chen、Qikai Kang、Po Zou
DOI:10.1039/c1cc14861c
日期:——
The direct and regioselective N-alkylation of amino-azoles to the corresponding 2-N-(alkylamino)azoles using various alcohols as alkylating agents with good to excellent yields has been accomplished by an iridium complex/base system.
which prevails in versatile natural products and biologically active compounds. Herein, a switchable and scalable C–N coupling protocol was developed for the synthesis of these compounds from 2-chlorobenzothiazoles and primary amines. Gratifyingly, this protocol was achieved under transition-metal-free and solvent-freeconditions. Moreover, introducing an appropriate amount of NaH completely switched
2-氨基苯并噻唑包含一个有价值的结构基序,它普遍存在于多功能天然产物和生物活性化合物中。在此,开发了一种可切换和可扩展的 C-N 偶联方案,用于从 2-氯苯并噻唑和伯胺合成这些化合物。令人欣慰的是,该协议是在无过渡金属和无溶剂条件下实现的。此外,引入适量的 NaH 将选择性从单杂芳基化完全转变为二杂芳基化,进一步的研究为这一新发现提供了基本原理。此外,代表性产物3a和4a 的克级合成通过应用操作简单且无需手套箱的程序来实现,这揭示了这项工作的实际实用性。最后,量化绿色指标的评估提供了证据,证明我们的协议在绿色化学和可持续性方面优于文献。
Control of selectivity in the preparation of 2-substituted benzoazoles by adjusting the surface hydrophobicity in two solid-based sulfonic acid catalysts
作者:Babak Karimi、Akbar Mobaraki、Hamid M. Mirzaei、Hojatollah Vali
DOI:10.1039/d2ob02274e
日期:——
A series of metal-free tandem reactions for the synthesis of pharmaceutically important 2-substituted benzoazoles from isothiocyanates and 2-aminothiophenol under catalyst-free conditions in the presence of Et-PMO-Me-PrSO3H (1a) and SBA-15-PrSO3H (1b) as solid acids were carried out in a highly selective way under solvent free conditions. A significant selectivity changeover toward either 2-mercaptobenzoxazole
An Fe(III) catalyzed, efficient methodology for the synthesis of 2-aminobenzothiazole derivatives in water was established. This mild, base-free, one-pot strategy showcases the reaction of readily available 2-bromophenyl isothiocyanate with a broad range of substituted amines such as aliphatic, aromatic, primary, secondary and cyclic amines under air. Notably, the reaction afforded the corresponding