Metal-directed and ligand-distorted assembly of chiral/achiral one-dimensional coordination polymers: Syntheses, structures and physical properties

MnII and CoII Coordination Polymers Showing Field-Dependent Magnetism and Slow Magnetic Relaxation Behavior

“…Br-isophthalic acid along with different types of auxiliary ligands has been previously used by different groups to prepare a variety of coordination polymers. − However, the present crystal structures reveal marked differences as compared to previous literature reports in various aspects such as in the binding modes of the carboxylate group, observed coordination environments around the metal centers, topological features, supramolecular interactions, dimensionality, etc. For example, when Br-H 2 isa and bpp (bpp = 1,3-bi­(4-pyridyl)­propane) were used as the starting material by Han et al, {[Mn 3 ­(H 2 O) 2 ­(H-bpp) 2 ­(Br-isa) 4 ]·​H 2 O} n was obtained .…”

“…In this respect, the isotropic Mn II ions and the highly anisotropic Co II ions (with large residual orbital contribution) impart interesting magnetic properties to the CPs. − We report in this work on four new Mn II - and Co II -based CPs that have been synthesized using 5-bromoisophthalic acid (Br-H 2 isa) as bicarboxylic acid along with N , N ′-bipyridyl derivatives as the ancillary ligands (Scheme ). The Br-H 2 isa ligand, with a 120° angle between two carboxylic groups, has been used earlier as a useful building block in generating attractive polymeric architectures. − Moreover, the electron-withdrawing Br-substituent may take part in secondary hydrogen or halogen bonding to reinforce the supramolecular structure that forms. The bipyridyl linkers introduce an additional binding dimension to the complexes.…”