Chemically functionalized MIL-101-NH2 with cobalt(II) tetrasulfophthalocyanine: an efficient catalyst for the aerobic oxidation of alcohols and one-pot tandem conversion of alcohols to propargylamines

A sustainable protocol for selective alcohols oxidation using a novel iron-based metal organic framework (MOF-BASU1)

The selective oxidation of active and inactive alcohol substrates is a highly versatile conversion that poses a challenge in controlling the functionality and adjustments on MOFs. On the other hand, it offers an attractive opportunity to expand their applications in designing the next generation of catalysts with improved performance. Herein, a novel iron-based MOF containing sulfonamide (MOF-BASU1) has been fabricated by the reaction of 1,3-benzene disulfonylchloride linker and FeCl3·6H2O. Based on the results, the active surface area of the synthesized MOF is large, which highlights its unique catalytic activity. Optimum conditions were reached after 0.5-2 h, with 15 mg loading of the synthesized MOF under optimal conditions. Furthermore, the turnover frequency was 18-77.6 h-1, which is comparable to values previously reported for this process. Overall, the high catalytic activity observed for MOF-BASU1 might be because of the obtained high surface area and the Lewis acidic Fe nodes. Furthermore, the MOF-BASU1 revealed a remarkable chemoselectivity for aldehydes in the presence of aliphatic alcohols. Overall, the high product yields, facile recovery of nanocatalysts, short reaction times, and broad substrate range make this process environmentally friendly, practical, and economically justified.

Pd-Coordinated Salinidol-Modified Mixed MOF: An Excellent Active Center for Efficient Nitroarenes Reduction and Selective Oxidation of Alcohols

Selective oxidation of active and inactive alcohol substrates and reduction of nitroarenes is a highly versatile conversion that remains a challenge in controlling functionality and adjustments in metal-organic frameworks (MOFs). On the other hand, it offers an attractive opportunity to expand their applications in designing the next generation of catalysts with improved performance. Herein, a novel mixed MOF consisting of supported 2-hydroxybenzamide (mixed MOF-salinidol) has been fabricated by post-synthetic modifications of mixed MOF. Subsequently, the prepared nanocomposites were modified to impart catalytic sites using palladium chloride ions mixed with MOF-salinidol/Pd (II). After successfully designing and structurally characterizing nanocomposites, we evaluated their activity in oxidizing primary and secondary alcohols using aerobic conditions with molecular oxygen and an air atmosphere. In addition, the stability of (mixed MOF-salinidol/Pd (II)) catalysts under catalytic conditions was also demonstrated by comparing the Fourier-transform infrared spectrum, scanning electron microscopy image, and ICP-OES method before and after catalysis. Based on the results, the active surface area of the synthesized nanocatalyst is large, which highlights its unique synergistic effect between post-synthetic modified MOF and Pd, and furthermore, the availability of catalytic sites from Pd, as demonstrated by outstanding catalytic activity.

Cobalt isatin-Schiff-base derivative of MOF as a heterogeneous multifunctional bio-photocatalyst for sunlight-induced tandem air oxidation condensation process

A sunlight-induced tandem air oxidation-condensation of alcohols with ortho-substituted anilines or malononitrile for the efficient synthesis of benz-imidazoles/-oxazoles/-thiazoles, or benzylidene malononitrile catalyzed by Co-isatin-Schiff-base-MIL-101(Fe) as a heterogeneous multifunctional bio-photocatalyst is reported. In these reactions, Co-isatin-Schiff-base-MIL-101(Fe) acts both as a photocatalyst, and a Lewis acid to catalyze the reaction of the in-situ formed aldehydes with o-substituted anilines or malononitrile. A significant decrease in the band gap energy and an increase in the characteristic emission of MIL-101(Fe) after functionalization with cobalt Schiff-base according to the DRS analysis and fluorescence spectrophotometry, respectively, indicate that the photocatalytic effectiveness of the catalyst is associated primarily to the synergetic influence of Fe-O cluster and Co-Schiff-base. EPR results obviously pointed out that Co-isatin-Schiff-base-MIL-101(Fe) is capable of creating ¹O₂ and O₂^⋅- as active oxygen species under visible light irradiation. Using an inexpensive catalyst, sunlight irradiation, air as a cost-effective and abundant oxidant, and a low amount of the catalyst with recoverability and durability in ethanol as a green solvent, make this methodology as an environmentally friendly process with energy-saving organic synthetic strategies. Furthermore, Co-isatin-Schiff-base-MIL-101(Fe) displays excellent photocatalytic antibacterial activity under sunlight irradiation against E. coli, S. aureus and S. pyogenes. Based on our knowledge, this is the first report of using a bio-photocatalyst for the synthesis of the target molecules.