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Herein, we report the syntheses and characterization of two novel CdII-based metal–organic frameworks (MOFs) with the formulae: [{Cd(INH)(hpdia)}·3H2O]α (Cd-MOF-1) and [{Cd(INH)(bdc)}·DMF]α (Cd-MOF-2) (INH = isoniazid, hpdia = 5-(4-hydroxyphenylazo)isophthalic acid, and H2bdc = 1,4-benzenedicarboxylic acid) using the mixed ligand and solvothermal protocol. Single crystal X-ray analysis reveals that Cd-MOF-1 and Cd-MOF-2 display overall 2D porous framework architectures. Cd-MOF-1 and Cd-MOF-2 have a two-dimensional zigzag network composed of a 4-connected uninodal network with sql topology and point symbol {4·4·6·2}. TGA analysis suggests that Cd-MOF-1 and Cd-MOF-2 are thermally stable. These MOFs exhibit fascinating luminescence properties. Cd-MOF-2 shows intense blue emission whereas Cd-MOF-1 shows nearly visibly intense white light emission with a CIE index of (0.34, 0.32) having a color correlated temperature (CCT) of 5121 K. Herein, we show how one can tune their spectral output by varying the emissive and non-emissive organic linkers. [ABSTRACT FROM AUTHOR]

We report the syntheses and structural characterization of a Zn(II) metallacycle [Zn2{(L)2(DMF)2(NO3)2}]·(NO3)2 (1) along with a Cd(II) coordination polymer [{Cd1(L)2(DMF)2}·(NO3)2]n (2) (where L = N,N′-bis-(3-pyridyl)terephthalamide; DMF = dimethylformamide) and their utilization as fluorescent probes for highly selective recognition (turn-off) of Fe3+ and CrO42− ions. Compounds 1 and 2 were prepared by utilizing ligand L and the nitrate salt of zinc and cadmium, respectively. Single crystal X-ray analysis reveals that 1 adopts an overall Zn(II) metallacycle architecture, whereas 2 displays a one-dimensional (1D) polymeric structure. Both 1 and 2 showed high fluorescence stability in aqueous solution and selectively detected Fe3+ and CrO42− ions with high quenching constants and low detection limits of 2.34 × 106 M−1 and 0.153 μM for Fe3+, 6.72 × 105 and 0.205 μM for CrO42− (for 1); 3.25 × 106 and 0.193 μM for Fe3+, 6.94 × 105 and 0.155 μM for CrO42− (for 2). Notably, ligand L itself did not display any type of recognition for any ions in DMF as well as in aqueous media. Moreover, 1 and 2 were also employed as heterogeneous catalysts for the ring-opening reaction (ROR) of epoxides with various assorted amines and up to 95% yield (TON, 47.5 and TOF, 11.9 h−1) was observed with perfect regioselectivity in the case of styrene oxide. [ABSTRACT FROM AUTHOR]