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A pyridine–tricarboxylic acid, 4-(6-carboxy-pyridin-3-yl)-isophthalic acid (H3cpia), was used as a versatile building block to synthesize three novel coordination polymers under hydrothermal conditions and formulated as [Mn8(μ3-Hcpia)2 (μ6-cpia)4(Hbiim)2(H2O)6]n·6nH2O (1), [Cu3(μ4-cpia)2(bipy)2(H2O)2]n·4nH2O (2), and [Ni3(μ3-cpia)2(dpe)3(H2O)2]n·4nH2O (3). Three supporting ligands, 2,2′-biimidazole (H2biim), 2,2′-bipyridine (bipy), and 1,2-di(4-pyridyl)ethane (dpe), were used in the synthesis. The structures of the studied products 1–3 varied significantly, ranging from a 1D chain (2) to 2D sheets (1 and 3). Furthermore, these compounds were evaluated as heterogeneous catalysts for the Henry reaction, achieving high product yields under optimized conditions. In addition, we investigated various reaction parameters and substrate scopes, and assessed the feasibility of catalyst recycling. This thorough investigation’s results highlight the versatility of H3cpia as a tricarboxylate building block in the formation of functional coordination polymers.

A pyridine-tricarboxylic acid, 5-(3′,5′-dicarboxylphenyl)nicotinic acid (H3dpna), was employed as a adjustable block to assemble a series of coordination polymers under hydrothermal conditions. The seven new coordination polymers were formulated as [Co(μ3-Hdpna)(μ-dpey)]n·nH2O (1), [Zn4.5(μ6-dpna)3(phen)3]n (2), [Co1.5(μ6-dpna)(2,2′-bipy)]n (3), [Zn1.5(μ6-dpna)(2,2′-bipy)]n (4), [Co3(μ3-dpna)2(4,4′-bipy)2(H2O)8]n·2nH2O (5),[Co(bpb)2(H2O)4]n[Co2(μ3-dpna)2(H2O)4]n·3nH2O (6), and [Mn1.5(μ6-dpna)(μ-dpea)]n (7), wherein 1,2-di(4-pyridyl)ethylene (dpey), 1,10-phenanthroline (phen), 2,2′-bipyridine(2,2′-bipy),4,4′-bipyridine(4,4′-bipy),1,4-bis(pyrid-4-yl)benzene (bpb), and 1,2-di(4-pyridyl)ethane (dpea) were employed as auxiliary ligands. The structural variation of polymers 1–7 spans the range from a 2D sheet (1–4, 6, and 7) to a 3D metal–organic framework (MOF, 5). Polymers 1–7 were investigated as heterogeneous catalysts in the Knoevenagel condensation reaction, leading to high condensation product yields (up to 100%) under optimized conditions. Various reaction conditions, substrate scope, and catalyst recycling were also researched. This work broadens the application of H3dpna as a versatile tricarboxylate block for the fabrication of functional coordination polymers.

Three new products, [Cu2(μ3-dppa)(2,2′-bipy)2(H2O)]n·2nH2O (1), [Co4(μ4-dppa)2(phen)4(H2O)4]·2H2O (2), and [Co2(μ6-dppa)(μ-4,4′-bipy)(H2O)2]n·3nH2O (3) were synthesized using a hydrothermal method from Cu(II) and Co(II) metal(II) chlorides, 3-(3,4-dicarboxyphenoxy)phthalic acid (H4dppa), and different auxiliary ligands, namely 2,2′-bipyridine (2,2′-bipy),1,10-phenanthroline (phen), and 4,4′-bipyridine (4,4′-bipy). Products 1–3 were characterized by elemental analysis, FTIR, TGA, PXRD, SEM, and single-crystal X-ray crystallography. The structure of 1 features a 1D chain of the 2C1 topological type. Compound 2 shows a discrete tetrameric complex. Product 3 demonstrates a 3D metal–organic framework (MOF) with the new topology. Their structure and topology, thermal stability, and catalytic activity were studied. In particular, excellent catalytic activity was demonstrated for copper(II)-polymer 1 in the cyanosilylation reaction at 35 °C.

Using 57 universities directly under the Ministry of Education of China from 2009 to 2017 as the research samples, the overall efficiency, technology research efficiency, result transformation efficiency and efficiency influencing factors of the transformation of scientific research results in universities were explored using the leader-follower model in two-stage network Data Envelopment Analysis (DEA) and Tobit regression model, respectively. It is found that: firstly, the overall low efficiency of the scientific research results is primarily caused by the low efficiency of the transformation stage, which is on a downward trend and has lower average efficiency than the technology research stage. The efficiency of the technology research stage is on an upward trend, while the efficiency of the transformation stage is on a downward trend. Secondly, the number of universities reaching DEA effective in results transformation stage is more than that of technology R&D stage; Thirdly, the overall efficiency and result transformation efficiency of “985” universities are better than those of non-“985” universities, but the efficiency of technology R&D is lower than that of non-“985” universities; Fourthly, regional economic strength, government’s financial investment, the quality of patents, the number of papers, and the other eight factors all have an impact on efficiency.