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A benign and straightforward method to access quinazolinones have been developed using easily preparable Cu3(BTC)2 MOF as a sustainable solid‐Lewis acid catalyst under mild condition. Cu3(BTC)2 MOF was prepared and characterized using various analytical tools such as PXRD, FT‐IR, SEM, TGA, and ICP‐OES. Synthesis of the quinazolinone is catalyzed by the presence of coordinatively unsaturated open CuII sites in Cu3(BTC)2 MOF using renewable ethanol as a solvent with minimum copper loading (0.07 mmol) without any harsh reaction condition. A series of substituted quinazolinones were synthesized with good to excellent yields. The efficiency of the present framework copper catalysts was rationalized by comparing with other MOFs and homogeneous catalytic systems. The stability of the catalyst was demonstrated by six consecutive runs and heterogeneity test, which was also evidenced from the technical supports such as PXRD, FT‐IR and SEM analyses of the recovered catalyst. [ABSTRACT FROM AUTHOR]

An iron‐based metal‐organic framework, Fe(BTC) has been used as an efficient heterogeneous and sustainable catalyst for the synthesis of 2,4‐diarylquinolines via three‐component Povarov reaction. The presence of a high concentration of coordinatively unsaturated Fe3+ sites of Fe(BTC) efficiently catalyzes the formation of diarylquinolines in the presence of environmentally friendly air as an oxidant. The present methodology avoids the stoichiometric amount of catalyst and sensitive reagents. A series of 2,4‐diarylquinolines have been synthesized via Povarov synthesis in good to excellent yields with good functional group tolerance. The catalyst was easily separated by simple filtration and reused for more than five times without any remarkable loss in activity. Hot filtration test, FTIR, PXRD and SEM characterizations of reused catalyst confirmed the true heterogeneity and the stability of the catalyst. The efficiency of Fe(BTC) catalyst is compared with other homogeneous catalytic systems which enlighten the uniqueness of the present methodology. [ABSTRACT FROM AUTHOR]

A straightforward and efficient methodology for the one-pot multicomponent synthesis of 1,4-dihydropyridine has been developed using MIL-101-SO3H metal–organic framework as a solid Brønsted acid. The presence of the uniformly distributed Brønsted acidic sulfonic acid sites throughout the framework and the high stability bestow the catalyst with excellent reactivity towards the synthesis of 1,4-dihydropyridine under simple reaction conditions using renewable ethanol as the solvent. The present methodology tolerates various functional groups and allows the synthesis of 1,4-dihydropyridine derivatives in good to excellent yields through Hantzsch reaction. The developed methodology proceeds under mild conditions, avoids corrosive reagents and special reaction conditions, and is amenable to gram scale synthesis. The sustainable nature of the catalyst was proved by the easy recovery and the reusability of the catalyst, as it was reused several times without loss in activity, which was confirmed from the FTIR, PXRD and SEM analyses of the reused catalyst. [ABSTRACT FROM AUTHOR]

A convenient and environmentally benign synthesis of N-arylimidazoles has been demonstrated by a straightforward reaction catalyzed by the unsaturated coordination sites of Cu in the copper terephthalate metal-organic framework (Cu(tpa)-MOF). A series of N-arylimidazoles has been synthesized in excellent yields by the C−N cross-coupling reaction of arylboronic acids and imidazoles catalyzed by the Cu(tpa)-MOF using ethanol as a benign solvent. The present ligand-free catalytic system proceeds smoothly under mild conditions, avoids stoichiometric Cu reagents, tolerates many functional groups, has a wide substrate scope, and is feasible with other nitrogen heterocycles. The stability and heterogeneity of the catalyst is evidenced by the results of a heterogeneity test, and the catalyst can be reused several times without a loss of activity. The easy preparation of the catalyst, its stability, recovery by simple filtration, and reusability reveal Cu(tpa) MOF as a versatile catalyst for academic and industrial applications. [ABSTRACT FROM AUTHOR]

A straightforward and mild oxidative ipso -hydroxylation of arylboronic acids has been achieved using a simple and non-noble metal, nickel-based reusable heterogeneous catalyst Ni(HBTC)BPY MOF (HBTC = benzene-1,3,5-tricarboxylate, BPY = 4,4′-bipyridine) in the presence of benign hydrogen peroxide as an oxidant under ambient reaction condition. The Ni(HBTC)BPY MOF exhibits excellent catalytic activity towards the formation of phenols from diverse arylboronic acids within short time and can be reused up to five times without any notable loss in its activity as well as shown high functional group tolerance even in the presence of sensitive functionalities and useful to achieve hydroxyl group in heterocycles. Unlabelled Image • The first report on heterogeneous nickel as a catalyst for ipso -hydroxylation of arylboronic acids • Ni(HBTC)BPY MOF was used as a heterogeneous catalyst for ipso -hydroxylation under mild condition. • Chemoselective towards ipso -hydroxylation in the presence of sensitive functional groups • Short reaction time with a minimum oxidant load and renewable ethanol as a greener solvent • Ni(HBTC)BPY MOF is stable and reusable for several cycles with excellent catalytic efficiency. [ABSTRACT FROM AUTHOR]