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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]

This work presents the synthesis and characterization of two Cu(ii)-based coordination polymers prepared by utilizing two different Co(iii)-based metalloligands offering appended arylcarboxylic acid groups. Both coordination polymers are three-dimensional in nature and present pores and channels filled with water molecules. Both coordination polymers function as heterogeneous catalysts for the epoxidation of various olefins using O2 while employing isobutyraldehyde as the coreductor and for peroxide-mediated oxidation of assorted benzyl alcohols. The catalytic results illustrate efficient oxidation reactions, whereas the hot-fltration test and leaching experiments indicate the true heterogeneous nature of the catalysis. [ABSTRACT FROM AUTHOR]

This work illustrates two Ni2+ based coordination polymers (CPs, 1-Ni and 2-Ni) synthesized using two related Co3+ based metalloligands offering appended arylcarboxylate groups. The crystal structure of 1-Ni displays a porous 3D network having well-defined major and minor pores whereas 2-Ni exhibits a somewhat densely packed structure. Both CPs supported the exchange of coordinated water molecules and the inclusion of iodine within their porous structure whereas binding studies illustrated that the Ni(ii) ion in these CPs can bind thiophenol, a reagent used in the C–S cross coupling reactions. The two CPs functioned as the reusable heterogeneous catalysts for the C–S cross coupling reactions between substituted aromatic halides and thiophenol as well as cyclohexanethiol and ethanethiol. [ABSTRACT FROM AUTHOR]