Copper Phthalate Coordination Polymers Incorporating Kinked Dipyridyl Ligands: An Unprecedented 8-Connected Network and One-Dimensional Chiral Nanobarrels with Hydrophobic Channels Constructed from Septuple Helical Motifs

摘要

Copper phthalate coordination polymers incorporating the kinked and hydrogen-bonding-capable imines 4,4'-dipyridyl_ketone (dpk) and 4,4'-dipyridylamine (dpa) have been prepared and structurally characterized by single-crystal X-ray diffraction. {[Cu(pht)(dpk)] _ 0.33CH_30H}_n (1; pht = phthalate) possesses helical subunits built from the fusion of [Cu(dpk)], 3-fold double helices and [Cu(pht)]_n 3-fold helices with opposite handedness. The resulting achiral [Cu(pht)(dpk)]_n helices are conjoined by bridging phthalate carboxylate oxygen atoms to construct {Cu_2O_2} dimeric units, which serve as 8-connected nodes for a three-dimensional (3D) coordination polymer lattice with an unprecedented 3~64~(12)5~86~2 topology, evocative of a 3D Kagome lattice. ([Cu_2(pht)_2(dpa)] _ H_2O}_n (2) manifests homochiral septuple left-handed [Cu_2O_2(dpa)]_n helices formed by copper ions, phthalate oxygen atoms, and dpa ligands. The septuple helices are bracketed by pht anions to construct chiral one-dimensional nanobarrels with solvent-free “star-shaped” channels. Compounds 1 and 2 display antiferromagnetic [J = _9.85(5) cm~(-1)] and ferromagnetic [J = +1.36(3) cm~(-1)] coupling across their {Cu_2O_2} dimeric units, respectively.