Constructions of Seven Noncovalent-Bonded 3D Supramolecules from Reactions of Zn(II)/Cd(II) with 4-Dimethylaminopyridine and Carboxylic Acids

Seven novel 4-dimethylaminopyridine(dmap)-based metal complexes of [Zn(dmap)(cna) 2 ] 2 ( 1 ) (Hcna = cinnamic acid), [Zn(dmap)(dcpa) 2 ] 2 ( 2 ) (Hdcpa = 2,6-dichlorophenylacetic acid), [Zn(dmap)(mpba) 2 ] 2 ( 3 ) (Hmpba = 3-phenoxybenzoic acid), [Zn(dmap)(bdmba) 2 ] 2 ( 4 ) (Hbdmba = 4-bromo-3,5-dimethoxybenzoic acid), [Cd(damp) 2 (ibfa) 2 (H 2 O) 2 ] ( 5 ) (Hibfa = ibuprofen), [Cd(dmap) 2 (H 2 O) 4 ]·(dnba) 2 ·H 2 O ( 6 ) (Hdnba = 3,5-dinitrobenzoic acid) and [Cd(dmap) 2 (bdmba) 2 (H 2 O)] ( 7 ) have been afforded by the introduction of the carboxylates as the auxiliary ligands and are structurally featured by distinct techniques of EA, IR spectra, TG and SCXRD analysis. The X-ray studies told that these complexes display mononuclear, binuclear to polymeric appearances with tetrahedral/square-pyramidal arrangement at the Zn 2+ , and octahedral/pentagonal-bipyramidal geometry for the Cd 2+ . The dmap in 1 – 7 are coordinated only in monodentate fashion with its ring N. The carboxylates coordinated to the metal ions in monodentate, chelating bidentate and bismonodentate bridging modes for 1 – 5 and 7 . The carboxylates at 6 did not coordinated to the Cd and exhibited only as the counter ion to balance the charge. The CH 3 ···O contacts from the N(CH 3 ) 2 of the dmap were built in all compounds, apart from 1 and 6 . The π-associates originating from the aryl kernel of the anions were existed in 2 – 3 and 6 – 7 . The intricate intra- and intermolecular classical H-bonds, CH···C, CH···O/CH 3 ···O, CH···CH/CH 3 ···CH/CH 3 ···CH 3 , CH···Cl, CH 3 ···Br, Br···Br, CH···π/CH 2 ···π/CH 3 ···π and π···π associations are elucidated by the X-ray crystallographic investigations, which push the discrete complexes into high-dimensional ordered supramolecular structures. Graphical Abstract In the seven prepared coordination complexes there are plenty of weak nonbonding interactions such as directional hydrogen bonds of O–H···O, intra- and interchain CH–C, CH–O/CH 3 –O, CH–CH/CH 3 –CH/CH 3 –CH 3 , CH–Cl, CH 3 –Br, Br–Br, CH–π/CH 2 –π/CH 3 –π and π–π interactions, on account of these collective weak interactions, these compounds displayed the 3D framework structures.