1006-99-1Relevant articles and documents
Metal free montmorillonite KSF clay catalyzed practical synthesis of benzoxazoles and benzothiazoles under aerobic conditions
Kummari, Vijaya Babu,Chiranjeevi, Kalavakuntla,Suman Kumar, Alleni,Kumar, Rathod Aravind,Yadav, Jhillu Singh
, p. 3335 - 3342 (2019)
An efficient method for the synthesis of benzoxazoles and benzothiazoles via montmorillonite KSF clay catalyzed condensation reaction between 2-aminophenols or 2-aminothiophenols and β-diketones is reported. The efficiency of the reaction reflects from the wide substrate scope with electronic differentiation on aryls. The reaction is metal free and proceeds without the exclusion of air or moisture, and further the catalyst can be recycled up to 3–5 catalytic cycles.
Sodium dichloroiodate promoted C-C bond cleavage: An efficient synthesis of 1,3-Benzazoles via condensation of o -amino/mercaptan/hydroxyanilines with β -diketones
Bhagat, Saket B,Ghodse, Shrikant M,Telvekar, Vikas N
, (2018)
An efficient aqueous sodium dichloroiodate (NaICl 2) mediated protocol is developed for the synthesis of benzofused azoles by the cyclization of 2-amino anilines/thiophenols/phenols with β-diketone compounds. The reactions gave moderate to good yield of the corresponding 2-substituted benzimidazoles/benzothiazoles/benzoxazoles under mild conditions. This tandem process involved a C-C bond cleavage and C-N bond formation. Graphical Abstract?: SYNOPSIS A facile and single protocol for the synthesis of three versatile 1,3-benzazoles viz 2-substituted 1H-benzimidazoles, benzoxazoles and benzothiazoles from readily available starting materials, 1,3-diketones and corresponding o-amino anilines/thiophenols/phenols, by aqueous sodium dichloroiodate (NaICl 2) mediated C—C bond cleavage has been developed. The reaction provides a rapid access to these 1, 3-benzazoles in good yields, thus speeding up the drug discovery process.[Figure not available: see fulltext.].
Eco-friendly atom-economical synthesis of 2-substituted-benzo[d]thiazoles and 2-substituted-benzo[d]oxazoles using 2-acylpyridazin-3(2H)-ones
Sung, Gi Hyeon,Lee, In-Hye,Kim, Bo Ram,Shin, Dong-Soo,Kim, Jeum-Jong,Lee, Sang-Gyeong,Yoon, Yong-Jin
, p. 3530 - 3535 (2013)
Efficient and green syntheses of heterocycles are of great importance. In this work, we have demonstrated the synthesis of benzo[d]thiazoles and benzo[d]oxazoles using 2-acylpyridazin-3(2H)-ones as acyl transfer agents under transition-metal-free and eco-
Solid phase synthesis of benzothiazole and thiophene derivatives based on resin-bound cyclic malonic acid ester
Huang, Xian,Tang, Jing
, p. 4851 - 4856 (2003)
A new method for the solid phase synthesis of benzothiazoles and 2-arylamino-3-carboxyl-4-hydroxy-5-arylthiophenes is described. Resin bound cyclic malonic acid ester was reacted with aryl isothiocyanates and then with bromine or α-bromoketones, followed by treatment with perchloric acid or sodium methoxide to afford substituted 2-methylbenzothiazoles or 2-arylamino-3-carboxyl-4-hydroxy-5-arylthiophenes, respectively, in high yields and purities.
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Lankelma,Sharnoff
, p. 2654,2656 (1931)
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Synthesis method of benzothiazole compound
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Paragraph 0044-0048, (2021/07/14)
The invention relates to a novel process for synthesizing benzothiazole compounds, which comprises the following steps of: (1) heating and stirring orthoester, o-aminothiophenol and derivatives thereof to react, monitoring the reaction process by TLC, and obtaining crude benzothiazole compounds after the reaction is finished; and (2) distilling the crude benzothiazole compound obtained in the step (1) or recrystallizing by using a solvent, and filtering to obtain the benzothiazole compound. According to the method, no solvent is added in the reaction process, the separation and purification process is optimized, and green production of fine chemicals is effectively achieved; and no catalyst is added, the operation is simple, the reaction time is remarkably shortened, the production efficiency of the product is improved, and the yield can reach 79%-90%. The problems of environmental pollution, potential safety hazards, harm to human health, resource waste and the like caused by the solvent are fundamentally solved, and the method has extremely high green industrialization value.
