Two 3D chiral coordination polymers with 4-connected 6~6topological net:synthesis, structure and magnetic properties

摘要

The hydrothermal reaction of Co(II)/Cu(II), 5-hydroxyisophthalic acid and dipyridophenazine leads tothe generation of two 3D chiral coordination polymers, [M(hip)(DPPZ)]_n (M = Co(1),Cu(2), H_2hip=5-hydroxyisophthalic acid, DPPZ = dipyridophenazine), which contain M-hip-M helical chains (M =Co, Cu) and possess a new four-connected 66 topological net. The resulting crystals were not a racemicmixture but an enantiomeric excess, which was confirmed by the measurement of optical rotation of thebulk samples using solid state vibrational circular dichroism (VCD) and solid circular dichroism (CD)based on the large crystals from one crystallization. The magnetic properties of 1 and 2 have beeninvestigated by variable-temperature magnetic susceptibility and magnetization measurements, and theresults reveal that antiferromagnetic interactions exist in 1 and 2.