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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]

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 series of compounds with the general formula A2MB2O6 (A = Zn, Ba, Pb; B = Pb, Ba, Zn, Cu) related to the kotoite structure has been prepared employing high-temperature solid state methods. The substitution of transition elements in place of Zn2+ ions resulted in colored compounds. The optical absorption spectra could be explained based on Tanabe-Sugano diagram and allowed d-d transitions. Dielectric studies on Ba2ZnB2O6, (Ba1.5Pb0.5)ZnB2O6, PbZn2B2O6, Pb1.5Zn1.5B2O6, BaZn2B2O6 and Pb2CuB2O6 at room temperature indicate reasonable values at low frequencies, which decrease on increasing frequencies. Magnetic study of synthesized single-phase compounds BaZnCoB2O6 and Pb2CuB2O6 have been performed. The substitution of Eu3+, Tb3+ and Tm3+ in place of Ba2+ in Ba2ZnB2O6, gives rise to the expected emission of red, green and blue colors. Suitable modifications of the different phosphors in Ba2ZnB2O6, resulted in white-light emission in Ba2ZnB2O6. The Pb2CuB2O6 compound was found to be a good catalyst in the ipso-hydroxylation of arylboronic acids., (© 2024 Wiley‐VCH GmbH.)

A straightforward and efficient method has been demonstrated for the oxidative coupling of terminal alkynes using a simple Cu 3 (BTC) 2 -metal organic framework as a sustainable heterogeneous copper catalyst. A series of symmetrical 1,3-diynes bearing diverse functional groups have been synthesized in moderate to excellent yields via a Cu 3 (BTC) 2 catalyzed Glaser-Hay reaction. The presence of the coordinatively unsaturated open Cu II sites in Cu 3 (BTC) 2 catalyzes the homocoupling in the presence of air, as an environment friendly oxidant without the use of external oxidants, ligands or any additives. The present methodology avoids stoichiometric reagents and harsher or special reaction conditions, and shows good functional group tolerance. The as-prepared catalyst could be separated easily by simple filtration and reused several times without any notable loss in activity. The hot filtration test has investigated the true heterogeneity of the catalyst. Additionally, the powder X-ray diffraction pattern of the reused catalyst revealed the high stability of the catalyst.