The reaction of H2C[(CBu t )2(NAr)2] (Ar = 2,6-Pr i 2C6H3) with AlEt3 in refluxing toluene gave HC[(CBu t )2(NAr)2]AlEt2 (1) in high yield. Treatment of 1 with 2 equiv of iodine in toluene yielded HC[(CBu t )2(NAr)2]AlI2 (2). Reduction of 2 with potassium resulted in the formation of the tert-butyl-substituted β-diketiminato aluminum(I) compound HC[(CBu t )2(NAr)2]Al (3). Reactions of 3 with isocyanides, H2O, and a bulky terphenyl azide were investigated. 3 reacted with 2 equiv of CNAr to give two C−C coupling products:  in dilute solution, the C−C coupling of two CNAr molecules was followed by the C−H activation of one of the CHMe2 groups on the Ar ring of CNAr, while in concentrated solution or in the presence of an excess of the isocyanide, the coupling was accompanied by cleavage of one of the C−N bonds of the ligand backbone. Reaction of 3 with the bulky azide 2,6-Ar2C6H3N3 yielded the C−H activation product 6. Hydrolysis of 3 in toluene afforded a hydroxyaluminum hydride. Compounds 1 and 3−5 were characterized by X-ray single-crystal analysis.

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In contrast to the broad use of terephthalic acid as a building block for generating metal–organic architectures, functionalized terephthalate ligands remain significantly less investigated. In the present study, 2-chloroterephthalic acid (CltaH2) was used as an unexplored linker for assembling a new series of metal­(II) coordination polymers (CPs) formulated as {[Cu2(μ-Clta)­(μ4 -Clta)­(bipy)2]­·2H2O} n (1), {[Cu2(μ-Clta)­(μ4 -Clta)­(phen)2]­·2H2O} n (2), [Co3(μ4 -Clta)3­(phen)2] n (3), {[Zn4(μ3-Clta)2­(μ4-Clta)­(μ3-OH)2­(phen)2]­·2H2O} n (4), {[Cd­(μ3 -Clta)­(phen)]­·H2O} n (5), [Co2(μ-Clta)­(μ4 -Clta)­(μ-bpa)2] n (6), [Zn2(μ4 -Clta)­(μ4 -biim)] n (7), and [Cd­(μ-Clta)­(H2biim)2] n (8). These compounds were prepared hydrothermally from the respective metal­(II) chlorides, CltaH2, and different N-donor supporting ligands acting as mediators of crystallization (i.e., bipy, 2,2′-bipyridine; phen, 1,10-phenanthroline; bpa, bis­(4-pyridyl)­amine; H2biim, 2,2′-biimidazole). The structures of the coordination polymers 1–8 range from one-dimensional chains (5 and 8) and two-dimensional layers (1–3) to three-dimensional (3D) frameworks (4, 6, and 7); the latter also include 3D + 3D interpenetrated examples (4, 6). Apart from different dimensionalities, the compounds also feature distinct topologies, namely, 3,4L13 in 1 and 2, 3,4,6L12 in 3, pcu in 4, SP 1-periodic net (4,4)­(0,2) in 5, sqc65 in 6, 2C1 in 8, and a new kir1 topology in 7. Given the similarity of the reaction conditions, the obtained wide diversity of structures is primarily determined by the type of metal­(II) node and/or crystallization mediator. All the CPs were also screened as heterogeneous catalysts in a model CO2 fixation reaction, namely, in the coupling of epoxide (epichlorohydrin) with carbon dioxide, under atmospheric pressure, and in the absence of added solvent, to produce the corresponding cyclic carbonate. The catalytic reactions were optimized for CP 4, which revealed the best activity (up to 71% product yields), good stability, and recyclability for up to four reaction steps. Finally, CPs 3–8 are the first examples of cobalt, zinc, and cadmium coordination compounds assembled from 2-chloroterephthalic acid, thus widening its very limited application in the design of functional metal–organic architectures.

Sugar alcohols are the prominent alternatives of sugars in food, medical, and health industries. The ruthenium supported on multiwalled carbon nanotubes (Ru/MWCNTs) catalysts were prepared based on the Ru valence regulation strategy and applied for selective sugar hydrogenation to prepare various sugar alcohols including xylitol, arabinitol, sorbitol, mannitol, and galactitol for the first time, with high selectivity (>99.0%) and yield (>98.0%) under mild conditions (≤110 °C, 3.0 MPa H2 pressure). The hydrogenation reaction of xylose was further optimized and under mild conditions (100 °C, 3.0 MPa H2 pressure, and 500 rpm), which were lower than ever reported for high efficient synthesis of xylitol, 99.8% xylose conversion and 99.0% xylitol yield were achieved after 120 min of reaction.