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1. Assembly of a 3D Cobalt(II) Supramolecular Framework and Its Applications in Hydrofunctionalization of Ketones and Aldehydes

   https://doi.org/10.3390/chemistry4020029  

   Zhang, Guoqi; Wang, Alex; Zeng, Haisu; Zheng, Shengping; Neary, Michelle C. (June 2022, Chemistry)

   A ditopic nitrogen ligand (E)-N′-(pyridin-4-ylmethylene)isonicotinohydrazide (L) containing both divergent pyridyl coordination sites and a hydrogen-bonding hydrazide–hydrazone moiety was synthesized. The Co(NCS)2-mediated self-assembly of L has resulted in the synthesis of a novel 3-dimensional (3D) supramolecular framework (1) that features both coordination and hydrogen bonding interactions. X-ray structural analysis reveals the formation and coordination mode of 1 in the solid state. The rational utilization of coordination bonds and hydrogen bonding interactions is confirmed and responsible for constructing the 3D materials. Catalytic studies using 1 in the presence of an activator are performed for the hydroboration and hydrosilylation reactions of ketones and aldehydes, and the results are compared with previously reported cobalt-based polymeric catalysts. 

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2. Homoleptic octahedral Co ^II complexes as precatalysts for regioselective hydroboration of alkenes with high turnover frequencies

   https://doi.org/10.1039/d3ra06113b  

   Zhang, Guoqi; Zeng, Haisu; Zadori, Nora; Marino, Camila; Zheng, Shengping; Neary, Michelle C. (September 2023, RSC Advances)

   Monoprotonated homoleptic complex of cobalt(ii) with 4′-pyridyl-2,2′;6′,2′′-terpyridine ligand is an efficient precatalyst for hydroboration of styrene derivatives with Markovnikov selectivity, displaying turnover frequencies up to 47 000 h⁻¹. 

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3. Templated interfacial synthesis of metal-organic framework (MOF) nano- and micro-structures with precisely controlled shapes and sizes

   https://doi.org/10.1038/s42004-021-00522-1  

   Meng, Lingyao; Yu, Binyu; Qin, Yang (June 2021, Communications Chemistry)

   Abstract Metal-organic frameworks (MOF) are an emerging class of microporous materials with promising applications. MOF nanocrystals, and their assembled super-structures, can display unique properties and reactivities when compared with their bulk analogues. MOF nanostructures of 0-D, 2-D, and 3-D dimensions can be routinely obtained by controlling reaction conditions and ligand additives, while formation of 1-D MOF nanocrystals (nanowires and nanorods) and super-structures has been relatively rare. We report here a facile templated interfacial synthesis methodology for the preparation of a series of 1-D MOF nano- and micro-structures with precisely controlled shapes and sizes. Specifically, by applying track-etched polycarbonate (PCTE) membranes as the templates and at the oil/water interface, we rapidly and reproducibly synthesize zeolitic imidazolate framework-8 (ZIF-8) and ZIF-67 nano- and micro structures of sizes ranging from 10 nm to 20 μm. We also identify a size confinement effect on MOF crystal growth, which leads to single crystals under the most restricted conditions and inter-grown polycrystals at larger template pore sizes, as well as surface directing effects that influence the crystallographic preferred orientation. Our findings provide a potentially generalizable method for controlling the size, morphology, and crystal orientations of MOF nanomaterials, as well as offering fundamental understanding into MOF crystal growth mechanisms. 

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4. Homogeneous versus MOF-supported catalysis: A direct comparison of catalytic hydroboration at Ni tripodal P ₃ E (E = Si, Ge) complexes

   https://doi.org/10.1039/D3DT01328F  

   Barrios-Vargas, Luz Jimena; Abeynayake, Niroshani Samitri; Secrist, Carlee; Le, Nghia; Webster, Charles Edwin; Donnadieu, Bruno; Kaphan, David M; Roy, Amitava; Ibarra, Ilich A.; Montiel-Palma, Virginia (January 2023, Dalton Transactions)

   MOF NU-1000 was employed to host Ni tripodal complexes prepared from new organometallic precursors [HNi(κ4(E,P,P,P)-E(o-C 6 H 4 CH 2 PPh 2 ) 3 ], E = Si (Ni-1), Ge (Ni-2). The new heterogenous catalytic materials, Ni-1@NU-1000 and Ni-2@NU-1000 show the advantages of both homogenous and heterogeneous catalysts. They catalyze the hydroboration of aldehydes and ketones more efficiently than the homogenous Ni-1 and Ni-2, under aerobic conditions, and allowing recyclability of the catalyst. 

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5. Hydrogen-Bonding Linkers Yield a Large-Pore, Non-Catenated, Metal-Organic Framework with pcu Topology

   https://doi.org/10.3390/molecules25030697  

   Yazdanparast, Mohammad S.; Day, Victor W.; Gadzikwa, Tendai (February 2020, Molecules)

   Pillared paddle-wheel-based metal-organic framework (MOF) materials are an attractive target as they offer a reliable method for constructing well-defined, multifunctional materials. A drawback of these materials, which has limited their application, is their tendency to form catenated frameworks with little accessible volume. To eliminate this disadvantage, it is necessary to investigate strategies for constructing non-catenated pillared paddle-wheel MOFs. Hydrogen-bonding substituents on linkers have been postulated to prevent catenation in certain frameworks and, in this work, we present a new MOF to further bolster this theory. Using 2,2′-diamino-[1,1′-biphenyl]-4,4′-dicarboxylic acid, BPDC-(NH2)2, linkers and dipyridyl glycol, DPG, pillars, we assembled a MOF with pcu topology. The new material is non-catenated, exhibiting large accessible pores and low density. To the best of our knowledge, this material constitutes the pcu framework with the largest pore volume and lowest density. We attribute the lack of catenation to the presence of H-bonding substituents on both linkers. 

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