Syntheses, structures and properties of two manganese(II) metal–organic frameworks based on bromoisophthalate and bipyridyl-type co-ligands

Abstract

Two new manganese(II) coordination polymers, [Mn 2 (bpe) 2 (4-Brip) 2 ] n ( 1 ) and {[Mn 3 (H 2 O) 2 (H-bpp) 2 (5-Brip) 4 ]·H 2 O} n ( 2 ), were prepared through hydrothermal reactions of Mn(II) acetate with H 2 -4-Brip or H 2 -5-Brip (H 2 -4/5-Brip = 4/5-bromoisopthaliac acid) and the bipyridyl-type co-ligands bpe or bpp (bpe = 1,2-bi(4-pyridyl)ethane and bpp = 1,3-bi(4-pyridyl)propane). The two complexes were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and X-ray single-crystal diffraction. Complex 1 has a complicated (3,5)-connected 3D 3-fold interpenetrating network with a Schläfli symbol of (4 2 .6 5 .8 3 )(4 2 .6), constructed of the ribbon-like chains having dimeric [Mn(COO)] 2 units bridged by 4-Brip. Complex 2 contains isophthalato-bridged trimanganese clusters as building units, which are linked by 5-Brip anions to form a 1D ladder-like chain with unidentate coordinated H-bpp decorated as pendants. And the chains are further linked by N H∙∙∙O and O H∙∙∙O hydrogen bonding to generate a 2D interlocked architecture. Dominant antiferromagnetic couplings were observed in complexes 1 and 2 . Two new manganese(II) coordination polymers were synthesized and characterized. Complex 1 exhibits a complicated 3D 3-fold interpenetrating network. Complex 2 possesses a 2D layer structure, and exists extensive hydrogen-bonding interactions. ► Two Mn(II) complexes were synthesized and characterized. ► Dominant antiferromagnetic couplings in 1 and 2 ► Compared with other isophthalate derivative complexes, the substituted groups have an effect on final structures.