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Hydrothermal reaction of cadmium nitrate, bis(4-pyridylmethyl)piperazine (4-bpmp), and a variety of cyclohexyldicarboxylate ligands generated three new coordination polymer solids that were structurally characterized via single-crystal X-ray diffraction. [Cd(cis-13cdc)(4-bpmp)]n (1, cis-13cdc = cis-1,3-cyclohexanedicarboxylate) shows a sawtooth (4,4) grid topology. [Cd2(trans-12cdc)2(4-bpmp)]n (2, trans-12cdc = trans-1,2-cyclohexanedicarboxylate) displays a unique 4,5-connected layered (46)(4664) topology with embedded [Cd2(trans-12cdc)2] ribbon motifs. {[Cd(cis-12chedc)(4-bpmp)]·0.25H2O}n (3, cis-12chedc = cis-1,2-cyclohex-4-enedicarboxylate) manifests a 3D 3,5-connected self-penetrated network with an unprecedented (426)(426583) topology. Thermal decomposition, luminescent, and nitroaromatic detection properties of these three new materials are discussed.

Hydrothermal reaction of either cobalt or cadmium nitrate, D-camphoric acid (H2cam), and conformationally flexible dipyridylamide ligands produced five coordination networks which were structurally characterized by single-crystal X-ray diffraction. {[Co2(DL-cam)2(bdn)]·2H2O}n (1, bdn = N,N′-(butane-1,4-diyl)dinicotinamide) possesses {Co2(OCO)4} paddlewheel dimer-based [Co2(DL-cam)2] grid layers pillared by bdn ligands into a 6-connected 41263pcu network. In contrast, the cadmium analog {[Cd2(D-cam)2(bdn)2]·5H2O}n (2) shows {Cd2(OCO)2} dimer-based [Cd2(D-cam)2] layers tethered by bdn ligands into an 8-connected 42464bcu network. {[Co2(D-cam)2(pdn)]·2H2O}n (3, pdn = N,N′-(propane-1,3-diyl)dinicotinamide) manifests a self-penetrated 446810 mab network in contrast to 1, and retains chirality. {[Cd2(D-cam)2(pdn)]·H2O}n (4) manifests {Cd2(OCO)4} paddlewheel dimer-based [Cd2(D-cam)2] grids, connected by exotridentate pbn ligands into a unique 3,7-connected 3D network with (3·52)(324456687) topology derived from a rare non-self-penetrated 4966acs topology sublattice. {[Co2(DL-cam)2(pedn)]·2H2O}n (5, pedn = N,N′-(pentane-1,5-diyl)dinicotinamide) shows a hybrid structure of discrete slabs of 3D pcu network with interleaved 2D hxl (3,6) layers at random intervals, instead of the self-penetrated mab network seen in 3. The specific coordination environments and dipyridylamide lengths result in control of topology and self-penetration in this series of coordination networks. The cadmium complexes 2 and 4 were assayed for luminescent and nitrobenzene detection properties. Thermal properties of 1–5 are also discussed.

Hydrothermal reaction of nickel nitrate, adipic acid, and a dipyridylamide ligand produced two coordination polymers which were structurally characterized by single-crystal X-ray diffraction. {[Ni2(adipate)2(3-pna)2(H2O)]·H2O}n (1, 3-pna = 3-pyridylnicotinamide) possesses carboxylate bridged {Ni(μ2-H2O)(OCO)2} dimeric units connected into (6,3) graphitic 2D layer motifs. Use of the isomeric 3-pyridylisonicotinamide (3-pina) afforded {[Ni2(adipate)2(3-pina)2(H2O)]·2H2O}n (2), which manifested similar {Ni(μ2-H2O)(OCO)2} dimeric units. Crystallographic disorder within the adipate ligands in 2 produced a 3D coordination polymer net that is a hybrid of a non-interpenetrated 3D 6-connected primitive cubic α-Po 41263pcu net and 2D 7-connected slab motifs with a pillared (3,6) triangular net 3641253 topology. Magnetic analysis for 1 revealed weak antiferromagnetic coupling (J = −0.36(1) cm−1 with g = 2.077(1)), while 2 exhibited weak ferromagnetic coupling (J = +0.51(2) cm−1 with g = 2.034(7)).

Hydrothermal synthesis has afforded divalent metal sulfate coordination polymers containing 3-pyridylisonicotinamide (3-pina), whose dimensionalities depend crucially on the specific metal used and sulfate binding mode. {[Co(H2O)4(3-pina)]SO4·5H2O}n (1) shows a 1D chain structure with unligated sulfate ions. {[Cu(SO4)(3-pina)(H2O)]·H2O}n (2) possesses a (4,4) grid structure formed by the linkage of copper sulfate 1D chains through 3-pina tethers. [Cd(SO4)(3-pina)(H2O)]n (3) has exotridentate sulfate ions and a 2-fold interpenetrated 3,5-connected binodal 3D network with a very uncommon (426)(426583) binodal topology. The topology of 3 differs greatly from those seen in analogous 4,4′-bpy phases, including a previously unidentified self-penetrated network. The sulfate linkages in 2 promote weak ferromagnetic coupling between copper ions along 1D [Cu(SO4)]n zig-zag chains, with g = 2.10(3) and J = 0.66(11) cm−1. The cadmium derivative 3 undergoes luminescence upon exposure to ultraviolet light (λmax ∼430 nm).

Hydrothermal reaction of divalent metal salts, phthalic acid (H2pht), and bis(4-pyridylformyl)piperazine (bpfp) has afforded two-dimensional (2-D) and three-dimensional (3-D) dual-ligand coordination polymers. Their topologies are influenced by the coordination environment of the metal, binding mode of the pht ligands, and ligation of bpfp formyl groups. {[Co(pht)(bpfp)(H2O)2]·H2O}n (1) displays acentric (4,4) grid layers. [Cu2(pht)2(bpfp)(H2O)2]n (2) exhibits binding of bpfp formyl oxygen atoms and a simple but previously unreported 4,4-connected binodal layer structure with (4.648)2(4264) topology. [Cd2(pht)2(bpfp)(H2O)2]n (3) manifests a 3-D structure built from the bpfp pillaring of [Cd(pht)(H2O)]n layer motifs. A 4,5-connected binodal net with rare (4462)(4466) tcs topology can be invoked for 3. Employment of the bpfp ligand affords topologies very different from those seen in many other divalent metal phthalate coordination polymers, including the heretofore unrecognized uninodal 6-connected 3-D self-penetrated 510647 topology in [Co(Hpht)2(bpy)]n (bpy = 4,4′-bipyridine). Dehydration and thermal properties of 1–3 are also discussed, along with the luminescent behavior of 3.

Three divalent metal coordination polymers and one molecular species containing 4,4′-dipyridylamine (dpa) and substituted malonate ligands have been prepared and structurally characterized by single crystal X-ray diffraction. The degree of substitution and different coordination environments promote significant structural diversity in this system. {[Cu(mmal)(Hmmal)(Hdpa)]·H2O}n (1, mmal = methylmalonate) crystallizes in an acentric space group and possesses 1-D coordination polymer chain motifs containing [Cu(OCO)]n linkages. {[Cu3(dmmal)2(dpa)3](ClO4)2·2H2O}n (2, dmmal = dimethylmalonate) manifests an unprecedented (4,5)-connected binodal network with (4462)(4664)2 topology, and contains equatorial–equatorial bridged linear {Cu3O2} trimeric units. {[Cd2(dmmal)2(dpa)(Hdpa)](ClO4)·2H2O·CH3CH2OH}n (3) displays (6,3) herringbone layers, while {[Co(dmmal)2(Hdpa)2]·6H2O} (4) has co-crystallized neutral coordination complexes and hydrogen-bonded hexameric water molecule aggregations. Ultraviolet irradiation of a sample of 3 resulted in blue-violet light emission due to π–π* transitions within the dpa and Hdpa+ ligands. Variable temperature magnetic studies indicated antiferromagnetic coupling along the {Cu(OCO)}n chains in 1 and within the {Cu3O2} linear trimers in 2.

Hydrothermal synthesis has afforded two divalent metal coordination complexes incorporating both fully deprotonated pyromellitate (pyro) anions and the kinked dipodal organodiimine 4,4′-dipyridylamine (dpa), {[Co(H2O)4(Hdpa)2][pyro]} (1) and {[H2dpa][Zn(pyro)]·2H2O} (2). Both new complexes were characterized by single crystal X-ray diffraction and spectral and thermogravimetric analyses. Complex 1 possesses discrete [Co(H2O)4(Hdpa)2]4+ cations linked into supramolecular 2-D (4,4) rhomboid grid layer motifs by hydrogen bonding between the unligated pyro anions and the aquo ligands. The pendant, monodentate Hdpa+ cations also engage in charge-separated hydrogen bonding to pyro anions in neighboring layers, resulting in a supramolecular 3-D structure with an unprecedented 6-connected 446108 topology. In contrast, 2 is a true coordination polymer, with divalent Zn atoms linked by ligated pyro anions into a binodal 4-connected PtS-type anionic network (4284 topology), which encapsulates H2dpa2+ cations and unligated water molecules within large incipient pores coursing through the structure. Irradiation of a solid sample of 2 with ultraviolet light resulted in blue-light emission, likely indicative of π–π* transitions within the orbital manifolds of both the pyro anions and unligated H2dpa2+ cations.

Combination of cobalt or zinc chloride, 4,4′-dipyridylamine (dpa) and 4,4′-biphenyldicarboxylic acid (H2BPDC) under hydrothermal conditions has afforded the neutral coordination complexes {[Co(Hdpa)2(BPDC)2]·2H2O} (1) and [Zn(dpa)2(HBPDC)2] (2). The pendant cationic termini of the Hdpa ligands and anionic uncoordinated BPDC carboxylate groups allow each molecular unit of 1 to engage in strong charge-separated N–H⋯O hydrogen bonding interactions to four neighboring molecules, thereby creating a two-dimensional (2-D) hydrogen bonded (4,4) rhomboid grid motif with extremely large ∼42 A × ∼25 A apertures. Intra-layer void space is minimized by the interpenetration of four other identical hydrogen bonded rhomboid grids. Although the pendant carboxylate groups in 2 are protonated, strong O–H⋯N hydrogen bonding occurs, resulting in a supramolecular interaction pattern virtually identical to that of 1. To the best of our knowledge complexes 1 and 2 represent the first observations of a five-fold interpenetrated 2-D hydrogen bonded rhomboid grid supramolecular architecture. Adjacent layers further connect into three dimensions (3-D) by either weaker hydrogen bonding mechanisms mediated by water molecules of crystallization (1) or crystal packing forces (2).

Hydrothermal reaction of cadmium nitrate, adipic acid (H2adp), and a pyridylnicotinamide precursor has afforded four new crystalline coordination polymer solids. The 1-D ribbon coordination polymer {[Cd2(adp)(nic)2(H2O)3(3-ampyr)]·5H2O}n (1, nic = nicotinate, 3-ampyr = 3-aminopyridine) resulted from in situ hydrolysis of the 3-pyridylnicotinamide (3-pna) precursor under basic conditions. Incipient voids within the crystal lattice of 1 contain T5(2)5(2)A(0) water molecule chains. Eschewing addition of extra base to the reaction mixture resulted in the isolation of the 3-D coordination polymer {[Cd2(adp)(nic)2(3-pna)2]·6H2O}n (2), in which some of the 3-pna starting material remains intact. The underlying 5-connected 4664bnn 3-D network of 2 arises from the linkage of similar ribbon motifs to those observed in 1. Use of either 3-pyridylisonicotinamide (3-pina) or 4-pyridylnicotinamide (4-pna) precursors avoids any amide hydrolysis, affording the decorated (4,4) grid 2-D coordination polymer {[Cd(adp)(3-pina)]·H2O}n (3) or the 1-D chain compound {[Cd(adp)(4-pna)2(H2O)2]·2H2O}n (4), respectively. Luminescent and thermal properties of these materials are also presented.

Hydrothermal synthesis has afforded a pair of divalent copper coordination polymers containing trans-1,4-cyclohexanedicarboxylate (t-14cdc) and one of two isomeric dipyridylamides, 3-pyridylnicotinamide (3-pna) or 3-pyridylisonicotinamide (3-pina). Both of these materials feature unprecedented 3-D topologies. [Cu(t-14cdc)(3-pna)]n (1) manifests [Cu(t-14cdc)]n 4·82 layers featuring embedded anti–syn axial–equatorial bridged [Cu(OCO)]n chain motifs, pillared by anti-conformation 3-pna ligands into a new yet very simple binodal 3,5-connected (4·6·8)(4·66·83) network topology. {[Cu2(t-14cdc)2(3-pina)2(H2O)]·5H2O}n (2) shows two different copper/t14cdc chain motifs with isolated copper ions and {Cu2O2} dimeric units, respectively. These are linked together by 3-pina ligands to afford a new self-penetrated 4,6-connected binodal net with (4·64·8)2(42·612·8) topology. Variable temperature magnetic susceptibility experiments reveal very weak ferromagnetism (g = 2.01(1), J = 0.04(1) cm−1) along the [Cu(OCO)]n chains in 1 and weak antiferromagnetism (g = 1.906(3), J = −3.4(3) cm−1) within the {Cu2O2} dimeric units in 2. Thermal properties are also presented.

Hydrothermal reaction of zinc nitrate, a four-carbon chain dicarboxylic acid, and one of three isomeric dipyridylamide coligands has afforded a family of six new coordination polymers, which have been structurally characterized by single-crystal X-ray diffraction. The binding modes and conformations of the dicarboxylate ligands and the nitrogen donor disposition within the dipyridylamide coligands provide crucial structure-directing roles in this system. {[Zn(fum)(3-pina)]·1.5H2O}n (1, fum = fumarate, 3-pina = 3-pyridylisonicotinamide) has a 4-fold interpenetrated 43628 sra topology. [Zn(fum)(4-pna)]n (2, 4-pna = 4-pyridylnicotinamide) possesses a 4-fold interpenetrated 66dia topology, while [Zn(fum)(4-pina)]n (3, 4-pina = 4-pyridylisonicotinamide) has a 2-fold interpenetrated 41263pcu topology with dimeric cluster nodes. [Zn3(mal)2(OH)2(4-pina)2]n (4, mal = maleate) has neutral [Zn3(mal)2(OH)2]n ribbons linked into a (3,6) triangular layer. [Zn(suc)(4-pina)]n (5, suc = succinate) displays an uncommon 6-connected self-penetrated 446108 mab topology, while instead [Zn(suc)(4-pna)]n (6) has a simple corrugated (4,4) grid structure. Thermal and luminescent properties of these new materials have also been investigated.

The structures of luminescent divalent zinc coordination polymers containing a 5-substituted isophthalate ligand and the long-spanning hydrogen-bonding capable tethering ligand bis(4-pyridylmethyl)piperazine (bpmp) show a wide variety of two- and three-dimensional topologies. {[Zn(NO2ip)(Hbpmp)][ZnCl(H2O)(NO2ip)]}n (1, NO2ip = 5-nitroisophthalate) possesses parallel two-fold interpenetrated cationic (4,4) coordination polymer grids along with embedded anionic one-dimensional (1-D) chain motifs. The chloride-free derivative {[Zn5(NO2ip)6(Hbpmp)2(bpmp)]·2H2O}n (2) manifests trinuclear units linked into a complex doubly interpenetrated 4,8-connected binodal 3-D lattice with (456)2(414614) topology. {[Zn(OHip)(bpmp)]·H2O}n (3, OHip = 5-hydroxyisophthalate) has a five-fold interpenetrated diamondoid topology, while [Zn2(tBuip)2(bpmp)]n (4, tBuip = 5-tert-butylisophthalate) shows a two-fold interpenetrated primitive cubic net based on dimeric units. {[Zn(OMeip)(bpmp)]·8H2O}n (5, OMeip = 5-methoxyisophthalate) adopts an undulating (4,4) single-grid 2-D topology. {[Zn(sip)(Hbpmp)]·4H2O}n (6, sip = 5-sulfoisophthalate) displays a novel three-fold interpenetrated 3,5-connected binodal lattice with (426)(426583) topology.

Slow diffusion of aqueous solutions of cadmium salts with methanolic solutions of bis(4-pyridylformyl)piperazine (4-bpfp) generated crystalline coordination polymer phases whose dimensionality and topology are determined largely by the nature of the counteranion. [CdCl2(4-bpfp)]n (1) and [Cd(NO3)2(4-bpfp)]n (2) both possess 2-D coordination polymer layers via ligation of pyridyl nitrogen and amide carbonyl oxygen atoms. {[Cd(H2O)2(4-bpfp)](ClO4)2·4-bpfp·3H2O}n (3) forms similar layer motifs, but with unligated perchlorate anions and 4-bpfp molecules in the interlamellar regions. Use of the more basic sulfate anion produced {[Cd(SO4)(4-bpfp)(H2O)]·H2O}n (4), which has cadmium sulfate polymeric layers linked into a novel 3,5-connected binodal lattice with (4.62)(4.6683) topology by tethering 4-bpfp ligands. All species undergo blue-violet luminescence on exposure to ultraviolet light.

Divalent cobalt coordination polymers containing both phenylenediacetate (phda) and bis(4-pyridylmethyl)piperazine (4-bpmp) ligands display differing dimensionalities and topologies. The para-substituted 1,4-phda ligand afforded {[Co(1,4-phda)(4-bpmp)(H2O)2]·2H2O}n (1), a layered phase with standard (4,4) rhomboid grid topology. Use of the meta-substituted 1,3-phda ligand generated [Co(1,3-phda)(4-bpmp)]n (2), which has [Co(1,3-phda)]n layers pillared by pairs of 4-bpmp ligands into a three-dimensional (3D) coordination polymer with primitive cubic topology. Antiferromagnetically coupled {Co2(CO2)2} dinuclear units (J = −2.04(4) cm−1) are embedded within the structure of 2. The ortho-substituted derivative {[Co(1,2-phda)(4-bpmp)1.5(H2O)](H24-bpmp)0.5(ClO4)·12H2O}n (3) manifests an intriguing layered structure with 5-connected cobalt atom nodes and an Archimedean 334453cem topology with triangular and rectangular circuits.

Divalent copper coordination polymers containing flexible dipyridylpropane (dpp) and phenylenediacetate (phda) ligands display different metal cluster subunits and self-penetrated three-dimensional (3-D) topologies, depending on the disposition of the pendant arms within the anionic components. [Cu2(1,3-phda)2(dpp)]n (1) possesses dinuclear {Cu2(OCO)4} paddlewheel subunits linked into a 6-connected self-penetrated rob lattice with 48668 topology. {[Cu4(1,4-phda)3(OH)2(dpp)2]·2H2O}n (2) manifests non-cubane tetrameric {Cu4(OH)2}6+ kernels, connected into an 8-connected self-penetrated ilc lattice with 4245.63 topology. Antiferromagnetic coupling within the metal cluster subunits is observed in both 1 and 2.

The coordination polymer [Zn(mesaconate)(dpa)]n (1, dpa = 4,4′-dipyridylamine) has been prepared from the hydrothermal treatment of zinc chloride, dpa, and itaconic acid. An in situ terminal alkene to internal alkene isomerization occurred during self-assembly, unprecedented in coordination polymer chemistry. Single-crystal X-ray diffraction revealed that 1 crystallizes in the acentric space group Aba2, and features a parallel doubly interpenetrated (4,4)-rectangular layer morphology. Interlayer hydrogen bonding mediated by the dpa ligand results in a doubly interpenetrated (3,5)-connected supramolecular lattice with a novel (426)(426583) topology. Compound 1 undergoes blue-light emission upon exposure to ultraviolet radiation.

Hydrothermal synthesis has generated four divalent metal coordination polymers incorporating 2,2-dimethylsuccinate (dms) anions and the kinked and hydrogen-bonding capable tethering organodiimine 4,4′-dipyridylamine (dpa), which were characterized by single crystal X-ray diffraction and spectral and thermogravimetric analyses. [Co(dms)(dpa)] (1) contains tetrahedrally coordinated cobalt ions and displays a 3-D four-fold interpenetrated network with the 42638 sra topology. [Ni(dms)(dpa)] (2) by contrast manifests a 2-D rectangular grid morphology built from [Ni(dms)]n 1-D chains connected through dpa ligands. While [M(dms)(dpa)] (M = Cu, 3; M = Cd, 4) both possess doubly interpenetrated (4,4) rhomboid grid layers, 4 crystallizes in an acentric space group. Variable temperature magnetic studies indicated the presence of antiferromagnetic interactions in 2, with possible spin canting behavior evident at low temperatures. Ultraviolet irradiation of a sample of 4 promoted blue-violet light emission, likely arising from π–π* transitions within the dpa ligands.

Combination of divalent cobalt salts with the kinked and hydrogen-bonding capable organodiimine 4,4′-dipyridylamine (dpa) has afforded a family of coordination polymers where the anion plays a determining structure directing role. Use of the perchlorate salt results in the coordination polymer {[Co(H2O)2(dpa)2](ClO4)2·2 dpa·2 H2O} (1), which possesses cationic [M(H2O)2(dpa)2]n2n+ grid-like layer motifs. Unligated perchlorate anions, dpa molecules, and water molecules of crystallization are situated within the incipient rhomboid voids. Employing cobalt sulfate or nitrate as the metal source afforded {[Co(dpa)2(H2O)(SO4)]·2 H2O} (2) and {[Co(dpa)2(H2O)(NO3)](NO3)} (3), which display related 3-D quadruply interpenetrated [Co(dpa)2]n2n+ adamantoid frameworks. The cadmium perchlorate derivative {[Cd(H2O)2(dpa)2](ClO4)2·2 dpa·2 H2O} (4) displays a 2-D polymeric structure similar to that of 1. However 4 manifests a different layer stacking pattern from that in 1, revealing a subtle cation-based structure-directing effect. All materials were characterized via single crystal X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis.