π interactions (between pyrene rings) with a distance of 3.489 Å ( Supplementary Materials Figure S1A), N-H.
Moreover, these 2D hydrogen bonded networks are further connected via π
O interactions between the coordinated water molecules and the carboxylate-O atoms, forming a two-dimensional hydrogen bonded network.
The 1D chains of coordination polymer 1 are hydrogen bonded through several O-H ( C) Hydrogen bonded 1D chain of framework 1. ( B) Schematic representation of framework 1. The distance between two symmetry related Zn(II) ions in a chain is 10.239 Å, which is considerably larger than the shortest intermolecular distance of 5.412 Å between two metal ions in vicinal chains. The carboxylate groups, working in a monodentate fashion, are nearly in the plane of the isophthalate ring (dihedral angles of 8.53° and 12.92°). The observed non-planarity of the ligand is due to the relative twisting of the CH 2-NH group, and the C4-N1-C9-C10 torsional angle is 163.21°. The pyrene and isophthalate ring of the ligand are almost perpendicular with a dihedral angle of 73.34°. The metal ion binds two carboxylate oxygen atoms from two L 2− units and two water molecules the O–Zn–O bond angles fall within the range of 103.0(7)° to 119.7(9)°. The Zn(II) center presents a distorted tetrahedral environment (τ 4 = 0.91), and via the deprotonated L 2− ligand, it generates a 1D polymeric chain ( Figure 3C). The asymmetric unit of the coordination polymer 1 contains one zinc(II) ion, one L 2− ligand, two coordinated and one crystallization water molecules ( Figure 3A,B). Thus, we tested their heterogeneous catalytic activity towards the solvent-free microwave-assisted cyanosilylation reaction of different aldehydes under mild conditions. The insolubility and existence of both Lewis acid and basic (amine) centers in these CPs makes them favorable materials for bifunctional heterogeneous catalysis. They have been characterized by FTIR, thermogravimetric, elemental, and single-crystal and powder X-ray diffraction analyses.
n(H 2O) ( 2) are reported, being prepared by the solvothermal reactions of 5-isophthalic acid (H 2L) and constructed the one-dimensional n.
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