Three coordination polymers with helical chains based on methylenediisophthalic acid (H4MDIP)

Abstract

Based on methylenediisophthalic acid (H₄MDIP), three novel coordination polymers {[Mn₂(MDIP)(bime)(H₂O)₂]₂·2H₂O}_n (1) [bime = 1,2-ethanediylbis(imidazole)], {[Mn₃(HMDIP)₂(H₂O)₄]·4,4′-bipy·3H₂O}_n (2) [4,4′-bipy = 4,4′-bipyridine], and {[Co₅(MDIP)₂(H₂O)₆(μ-OH)₂]·7H₂O}_n (3) have been synthesized and characterized by IR spectra, single-crystal X-ray diffraction analyses and thermal stability studies. The introduction of the bime and 4,4′-bipy ligands into Mn(CH₃COO)₂·4H₂O and H₄MDIP system leads to the formation of complexes 1 and 2, and the absence of the second ligand in the Co(NO₃)₂·6H₂O and H₄MDIP system leads to shape complex 3. Complex 1 is a 3D architecture with [Mn(–OCO–)]_∞ helical chain. Coordination polymer2 is a 2D sheet structure with trinuclear unit, in which two kinds of 2₁ helical chains ([Mn(IP)]_∞ (IP = isophthalic acid) and [Mn(MDIP)]_∞) are included. Complex 3 exhibits the 3D porous structure with a pentanuclear cobalt unit in which a 1D shallow helical chain of hydrogen-bonded water molecules is shaped. From the topology point of view, complex 1 exhibits a (4,6)-connected network with the Schläfli symbol (4².6³.8)₂(4⁴.6².7⁴.8⁴.9), complex 2 displays a (3,6)-connected network with CdI₂ topology, and complex 3 displays a (4, 8)-connected network with Schläfli symbol (4⁴.6²)₂(4¹⁶.6¹²) which is a decorated scu net.