1233731-01-5Relevant academic research and scientific papers
Synthesis of benzothiazoles using fluorescein as an efficient photocatalyst under visible light
Chen, Haodong,Lei, Mayan,Liu, Chunyan,Sun, Wuji,Wang, Kaixuan,Wang, Xueyao,Zhong, Qidi
, (2021)
This work reports a novel and efficient method for the synthesis of benzothiazoles using 2-aminothiophenol derivatives in conjunction with aromatic aldehyde as starting materials via visible-light-induced condensation cyclization. Utilizing fluorescein as the photocatalyst and blue LED lamp as the light source, the reaction proceeds in the presence of a molecular oxygen atmosphere without the need for metal catalyst or an additional oxidant. Significantly, this method exhibits good tolerance in substrates, and a variety of 2-aminothiophenol derivatives and aromatic aldehyde are amenable to producing the corresponding benzothiazoles in high to excellent yields.
Urea nitrate–catalyzed C-N and C-S bond formation: A mechanochemical approach for 5-chloro-2-arylbenzo[d]thiazole derivatives
Sethiya, Ayushi,Sahiba, Nusrat,Soni, Jay,Agarwal, Shikha
, p. 873 - 881 (2021/02/01)
A series of substituted 5-chloro-2-arylbenzo[d]thiazoles were synthesized using 4-chloro-2-aminothiophenol and aromatic aldehydes in the presence of urea nitrate as a catalyst using the mechanochemical grindstone technique. This protocol was effectively carried out under metal-free conditions at room temperature, and the desired products were obtained in high to excellent yields in short reaction time (30–60 s). The structure of all the synthesized derivatives was confirmed by spectral characterization. The designed protocol has several benefits like eco-friendly, solvent-free, high yields, easy workup, and recyclability of catalyst. The catalyst was reusable at least four times without significant loss of activity. The good functional group tolerance with a series of derivatives has been demonstrated.
p-Toluenesulfonic acid-catalyzed metal-free formal [4?+?1] heteroannulation via N[sbnd]H/O[sbnd]H/S[sbnd]H functionalization: One-pot access to 2-aryl/hetaryl/alkyl benzazole derivatives
Srivastava, Abhijeet,Shukla, Gaurav,Singh, Maya Shankar
, p. 879 - 887 (2017/01/25)
A concise and direct one-pot [4?+?1] synthetic strategy for the construction of 2-substituted benzazoles such as benzoxazoles and benzothiazoles has been disclosed in high yields (80–98%) by cascade coupling reaction of 2-amino(thio)phenols with β-oxodithioesters. The current approach enables N[sbnd]H/O[sbnd]H/S[sbnd]H functionalization in one-pot under solventless condition leading to diverse benzazoles without use of any external metal. A wide range of 2-amino(thio)phenols and β-oxodithioesters are compatible toward this transformation with excellent functional group tolerance. Furthermore, we preempt the wider implications of this novel strategy by demonstrating its compatibility toward versatile diversification of DNA Topoisomerase-II inhibitors.
Ru(III)-catalyzed oxidative reaction in ionic liquid: An efficient and practical route to 2-substituted benzothiazoles and their hybrids with pyrimidine nucleoside
Fan, Xuesen,Wang, Yangyang,He, Yan,Zhang, Xinying,Wang, Jianji
experimental part, p. 3493 - 3496 (2010/08/20)
An efficient, practical and environmentally benign synthesis of 2-substituted benzothiazoles was developed through RuCl3-catalyzed oxidative condensation of 2-aminothiophenol with aldehyde in ionic liquid by using air as the oxidant. With this procedure, a series of 2-substituted benzothiazoles and benzothiazole/pyrimidine nucleoside hybrids with antimicrobial activities were efficiently prepared from easily accessible starting materials.
