title: A series of novel zinc(II) entangled coordination polymers based on carboxyphenyl-terpyridine ligands.
abstract: Hydrothermal synthesis has afforded five divalent zinc coordination polymers containing 4-(4-carboxyphenyl)-2,2':6',2''-terpyridine (HL1) or its isomer 4-(4-carboxyphenyl)-2,2':4',4''-terpyridine (HL2), with or without the addition of auxiliary ligands, 1,3,5-benzenetricarboxylic acid (H3btc) and 1,4-benzenedicarboxylic acid (H2bdc). Their structures have been characterized by single crystal X-ray analyses and further characterized by infrared spectra, elemental analyses, powder X-ray diffraction, thermogravimetric analyses and photoluminescent spectra. Across this series, the π···π interactions have a dramatic impact on the self-assembly of these entanglement structures, in either case it can exert an important structure-directing role. In addition, the disposition of pyridine nitrogen atoms in ligands also plays a large role in structure direction in this system. Complex 1 is a 2D + 2D→3D inclined polycatenated coordination polymer based on the resulting array of 2D (6,3) layers constructed by 1D→2D π···π directed self-assembly. Complex 2 is assembled into a 3D framework by means of 1D + 1D→3D mutual interdigitation based on 1D→1D self-assembly driven by π···π stacking interactions. Complex 3 shows a 2D + 2D→3D interdigital network involving 2D + 2D→2D parallel interpenetrated and 2D + 2D→2D interdigital (4,4) layer motifs. Complex 4 displays a 2D + 2D→3D polythreaded framework based on a 2D (4,4) network comprised of alternating rings and rods. Complex 5 is a (3,4)-connected 3D framework with topology (4.8(2).10(3))(4.8(2)). In comparison with covalently connected entanglements, such π···π directing self-assembly of entanglements are far less explored, especially, polycatenane based on 1D chain motifs and polythread based on 2D layer motifs are rarely reported. Furthermore, the luminescent properties of complexes 1-5 at room temperature have also been studied in detail herein.
authors.affiliation: State Key Laboratory of Structure Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, China.
authors.forename: Yan-Li
authors.initials: YL
authors.lastname: Gai
authors.forename: Fei-Long
authors.initials: FL
authors.lastname: Jiang
authors.forename: Lian
authors.initials: L
authors.lastname: Chen
authors.forename: Yang
authors.initials: Y
authors.lastname: Bu
authors.forename: Ming-Yan
authors.initials: MY
authors.lastname: Wu
authors.forename: Kang
authors.initials: K
authors.lastname: Zhou
authors.forename: Jie
authors.initials: J
authors.lastname: Pan
authors.forename: Mao-Chun
authors.initials: MC
authors.lastname: Hong
mesh_terms: D008024:Ligands; D008163:Luminescent Measurements; D008958:Models, Molecular; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D011108:Polymers; D011725:Pyridines; D015032:Zinc