Novel nickel‐based catalytic systems for the CHarylation of azoles with haloarenes and aryl triflates have been developed. We have established that Ni(OAc)2/bipy/LiOtBu serves as a general catalytic system for the coupling with aryl bromides and iodides as aryl electrophiles. For couplings with more challenging electrophiles, such as aryl chlorides and triflates, the Ni(OAc)2/dppf (dppf=1,1′‐bis
对于C新颖的镍基催化体系与卤代芳烃和芳基三氟甲磺酸酯唑h的芳基化得到了发展。我们已经确定,Ni(OAc)2 / bipy / LiO t Bu用作与芳基溴化物和碘化物作为芳基亲电子试剂偶联的一般催化体系。对于与更具挑战性的亲电试剂(例如芳基氯化物和三氟甲磺酸酯)偶联,发现Ni(OAc)2 / dppf(dppf = 1,1'-bis(diphenylphosphino)ferrocene)系统是有效的。噻唑,苯并噻唑,恶唑,苯并恶唑和苯并咪唑可用作杂芳烃偶联伴侣。经过进一步研究,我们发现了使用Mg(O t Bu)2进行本偶联的新方案作为LiO t Bu的温和且便宜的替代品。还描述了试图揭示这种镍催化的杂联芳基偶联机理的尝试。该新开发的方法已成功应用于非布索坦(一种有效治疗痛风和高尿酸血症的黄嘌呤氧化酶抑制剂),他法米第(一种有效治疗TTR淀粉样蛋白多神经病的药物)和texaline(一种天然的抗结核药物)的合成活动)。
KI-catalyzed arylation of benzothiazoles from the coupling of aryl aldehydes with benzothiazoles in neat water
作者:Yuyu Gao、Qiuling Song、Guolin Cheng、Xiuling Cui
DOI:10.1039/c3ob42318b
日期:——
A KI-catalyzed oxidative coupling of benzothiazoles with aryl aldehydes using TBHP as an oxidant in neat water under metal free conditions is described.
Direct Preparation of 2-Benzothiazolylzinc Bromide and its Applications: A Facile Synthetic Route to the Preparation of 2-Substituted Benzothiazole Derivatives
作者:Soo-Youl Park、Kyuhyuk Lee、Seung-Hoi Kim
DOI:10.5012/bkcs.2014.35.6.1848
日期:2014.6.20
methods A and C are relatively undeveloped. Interestingly, there is no report of synthesis utilizing method A, likely owing to the difficulty of preparing the corresponding organometallic reagents. In our continuing study on the application of organozinc reagents, we found that stable 2benzothiazolylzinc bromide (I) was easily prepared by the direct insertion of highly active zinc into 2-bromobenzothiazole
苯并噻唑部分已在多种天然产物和药物中发现,并显示出有效的生物活性。具体而言,2-取代的苯并噻唑衍生物由于其独特的结构性质在广泛的化学应用中引起了相当大的关注。因此,过去几十年来,合成方案的多样性一直是参与有机合成的科学家们广泛讨论的话题。一般来说,为了构建 2-取代的苯并噻唑配合物,策略工具可以分类为方案 1 所示:苯并噻唑基金属配合物的交叉偶联(方法 A),苯并噻唑通过直接氧化 CH 活化的偶联反应(方法 B),有机金属与卤代苯并噻唑的交叉偶联(方法 C),和含有N和S的化合物与适当的底物的环结构(方法D)。在这些工具中,方法 B 和 D 已被广泛探索。相比之下,尽管含过渡金属的有机金属配合物的有效性和效率,方法 A 和 C 相对不发达。有趣的是,没有使用方法A合成的报道,可能是由于难以制备相应的有机金属试剂。在我们对有机锌试剂应用的持续研究中,我们发现通过将高活性锌直接插入 2-溴苯并噻唑中很容易制备稳定的
Alumina as a Support and Catalyst for the Synthesis of Benzothiazoles in Solvent-free Condition
作者:Mei-Fang Ding、Chia-Pei Chen、Shaw-Tao Lin
DOI:10.1002/jccs.201200413
日期:2013.6
and benzothiazolylcoumarins (5) were prepared by the condensation of 2‐aminothiophenol (1) and hydroxybenzaldehydes (2) and 3‐ethoxycarbonylcoumarinnin (3), respectively, in solvent‐free condition. Of the solid support used, γ‐Al2O3 demonstrated the best activity. A linear regression line obtained from correlation between relative formation rate and Hammett constants with slope of 0.653 suggested that
One-pot tandem approach for the synthesis of benzimidazoles and benzothiazoles from alcohols
作者:Goravanahalli M. Raghavendra、Ajjahalli B. Ramesha、Cigalli N. Revanna、Kebbahalli N. Nandeesh、Kempegowda Mantelingu、Kanchugarakoppal S. Rangappa
DOI:10.1016/j.tetlet.2011.08.037
日期:2011.10
Propylphosphonic anhydride (®T3P) has been demonstrated to be an efficient and mild reagent for the one-potsynthesis of benzimidazoles and benzothiazoles from variety of alcohols. Mild conditions, short reaction time, broad functional group tolerance, low epimerization, easy and quick isolation of the products, excellent chemo selectivity, and excellent yields are main advantages of this procedure