Crystal Structures and Magnetic Properties of 2D Supramolecular Architectures Assembled from Benzimidazolecarboxylato‐Bridged 1D Double‐Stranded Coordinating Chains Featuring Metallomacrocycles as Subunits

Autor: Chuan-Min Qi, Song Gao, Yufeng Chen, Xiaojing Yang, Yong He, Die Zhang, Cuihong Fan, Hui Ma, Shulan Ma
Rok vydání: 2008
Předmět:
Zdroj: European Journal of Inorganic Chemistry. 2008:3776-3785
ISSN: 1099-0682
1434-1948
DOI: 10.1002/ejic.200800375
Popis: Two new 2D supramolecular architectures [{Mn2(L1)2(H2O)2}·2CH3OH]n (1) and [{Mn2(L2)2(CH3OH)4}·2CH3OH·4(H2O)]n (2) were assembled from the newly synthesised semi-rigid ligands H2L1 {2,6-bis[(6-carboxy-2,4-dimethylbenzimidazol-1-yl)methyl]pyridine} and H2L2 {2,6-bis[(6-carboxy-4-methyl-2-propylbenzimidazol-1-yl)methyl]pyridine} by reaction with MnII ions. They both contain novel 1D double-stranded coordinating chains with metallomacrocyclic subunits and dinuclear MnII subrings bridged by benzimidazolecarboxylato ions, the latter derived from the ligands. The differences in the steric hindrance of the methyl and propyl groups attached to the benzimidazole rings in H2L1 and H2L2 led to different coordinating modes of the carboxylato groups and, thus, aesthetically fascinating extended structures with useful magnetic properties. Variable-temperature susceptibility measurements (2–300 K) revealed antiferromagnetic coupling interactions (J = –0.23 cm–1 for 1 and –0.92 cm–1 for 2) with values being within the reported range but differing from each other due to the distinct bridging modes of the carboxylato ions. The different crystal structures and magnetic properties of 1 and 2 are discussed in detail.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Databáze: OpenAIRE
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