Indium-based metal–organic frameworks as catalysts: synthesis of 2-nitro-3-arylimidazo[1,2-a]pyridines via oxidative amination under air using MIL-68(In) as an effective heterogeneous catalyst

• Published in: RSC advances Vol. 7; no. 37; pp. 23073 - 23082
• Main Authors: Ha, Phuong T. M., Lieu, Thien N., Doan, Son H., Phan, Trang T. B., Nguyen, Tung T., Truong, Thanh, Phan, Nam T. S.
• Format: Journal Article
• Language: English
• Published: 01.01.2017
• Subjects: Catalysis; Catalysts; Deterioration; Efficiency; Metal-organic frameworks; Reuse; Synthesis (chemistry); Transformations
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/C7RA02802D

The metal–organic framework MIL-68(In) has emerged as a productive heterogeneous catalyst for the synthesis of 2-nitro-3-arylimidazo[1,2- a ]pyridines via oxidative amination between 2-aminopyridines and nitroalkenes using air as an oxidation agent. The catalyst displayed impressively higher efficiency for the generation of 2-nitro-3-arylimidazo[1,2- a ]pyridines than various other MOFs and several common homogeneous catalysts. Heterogeneous catalysis was verified for the reaction of 2-aminopyridines with nitroalkenes employing the framework-based catalyst. It was possible to collect and reuse the catalyst for the production of 2-nitro-3-arylimidazo[1,2- a ]pyridines without a pronounced deterioration in catalytic efficiency. To the best of our knowledge, the preparation of 2-nitro-3-arylimidazo[1,2- a ]pyridines has not been formerly conducted utilizing heterogeneous catalysts. Furthermore, indium-based catalysts were not previously employed for this transformation.