Construction of six Zn2+/Cd2+ supramolecules from 3, 5-dimethylpyrazole: their synthesis and characterization. Issue 11 (3rd June 2021)

• Record Type: Journal Article
• Authors: Bai, Liqun; Hu, Kaikai; Jin, Shouwen; Wen, Xianhong; Xu, Weiqiang; Wang, Daqi
• Is Part Of: Journal of coordination chemistry. Volume 74:Issue 11(2021)
• Page Start: 1834
• Page End: 1855
• Publication Date: 2021-06-03
• Subjects: Zn2+ -- Cd2+ -- coordination complexes -- 3, 5-dimethylpyrazole; Coordination compounds -- Periodicals; 541.2242
• DOI: 10.1080/00958972.2021.1935902
• Languages: English
• ISSNs: 0095-8972

Abstract

Abstract: The present report pertains to the synthesis and characterization of six complexes, [Zn2 (μ-dmpz)2 (Hdmpz)2 (H2 O)2 ](ClO4 )2 (1 ) (Hdmpz = 3, 5-dimethylpyrazole, dmpz = 3, 5-dimethylpyrazolate), Cd(Hdmpz)(L1)2 (2 ) (L1 = 2-methylbenzoate), [Zn2 (μ-dmpz)2 (Hdmpz)2 (L2)2 ] (3 ) (L2 = 3-chlorobenzoate), Zn(Hdmpz)2 (L3)2 (4 ) (L3 = 3, 4-dichlorobenzoate), Cd(Hdmpz)4 (L4)2 (5 ) (L4 = 5-bromosalicylate), and Zn2 (Hdmpz)4 (L5)2 ·3H2 O (6 ) (L5 = fumarate). These complexes were characterized by EA, IR, SCXRD analysis, and TGA. The X-ray studies show that these complexes have mononuclear to dinuclear structures with tetrahedral/octahedral arrangement around each Zn 2+ /Cd 2+ . The Hdmpzs in 2 and 4 –6 are monodentate ligated via its neutral N, while 1 and 3 have neutral Hdmpzs and the ionic dmpzs. The CO2 − of 3 –6 is only monodentate. Compound 2 has both monodentate bridging and chelating bidentate CO2 - . Intramolecular N–H···O H-bond from Hdmpz and ClO4 - was present in 1 . The coordinated O of CO2 - in 2 accepts an intramolecular N–H···O H-bond from N-H of the Hdmpz and uncoordinated O of the CO2 - in 3, 4 and 5 has an intramolecular N–H···O H-bond with N-H of the Hdmpz. Compound 6 has intramolecular N–H···O H-bonds from the Hdmpz, the uncoordinated O and H2 O. The intricate intra- and intermolecular classical H-bonds, Br···O, CH···Cl, CH3 ···Cl, CH···Br, C–H···O, CH3 ···O, C···π, O···π, O···C, Cl-π, C–H···π and CH3 ···π associations are elucidated by X-ray crystallographic studies, which convert discrete units into high-dimensional ordered supramolecular structures. Abstract :