Three Coordination Polymers Based on Resorcin[4]arene as Effective Catalysts for the Knoevenagel Condensation Reaction and as Multifunctional Luminescent Sensors

Three distinctive coordination polymers [Zn-2(m-bdc)(2)(L)]8DMF2CH(3)OH (1) [Zn-2(bpdc)(2)(L)]9DMF5CH(3)OH (2) and [Cd5Cl10(L)(2)]6DMA2CH(3)OH (3) were synthesized based on a novel pyridine-functional resorcin[4]arene ligand (L=tetrakis(4-mercaptopyridine-ylmethyl) resorcin[4]arene m-H(2)bdc=13-isophthalic acid H(2)bpdc=biphenyl-44 '-dicarboxylic acid and DMA=NN-dimethylacetamide). Among them 1 and 3 exhibit charming two-dimensional layers while 2 gives a three-dimensional framework. The performance of 1 and 3 was studied as solvent-free heterogeneous catalysts for Knoevenagel condensation reaction of which 1 shows an efficient catalytic capability for the reactions of various aldehydes with malononitrile. Apart from that the luminescent performance of 1 and 3 in a series of anions and cations were also explored. Their quenching to Cr2O72- CrO42- and Fe3+ ions makes 1 and 3 become promising luminescent sensors.