Solid state coordination chemistry: one-, two-, and three-dimensional materials constructed from molybdophosphonate subunits linked through binuclear copper tetra-2-pyridylpyrazine groups

The hydrothermal reactions of MoO(3), an appropriate Cu(II) source, tetra-2-pyridylpyrazine (tpypyz), and phosphoric acid and/or an organophosphonate yielded a series of organic-inorganic hybrid materials of the copper-molybdophosphonate family. A common feature of the structures is the entrainment within the extended architectures of chemically robust [Mo(5)O(15)(O(3)PR)(2)](4)(-) clusters as molecular building blocks. The cluster is a characteristic feature of the one-dimensional materials [[Cu(2)(tpypyz)(H(2)O)(3)]Mo(5)O(15)(HPO(4))(O(3)PCH(2)CO(2)H)].H(2)O (1.H(2)O) and [[Cu(2)(tpypyz)(H(2)O)]Mo(5)O(15)(O(3)PC(6)H(5))(2)].2H(2)O (2.2H(2)O), the two-dimensional network [[Cu(2)(tpypyz)(H(2)O)(3)]Mo(5)O(15)(HPO(4))(2)].2H(2)O (5.2H(2)O) and the three-dimensional frameworks [[Cu(2)(tpypyz)(H(2)O)(2)]Mo(5)O(15)[O(3)P(CH(2))(n)()PO(3)]].xH(2)O [n = 3, x = 2.25 (6.2.25H(2)O); n = 4, x = 0.33 (7.0.33H(2)O)]. In the case of methylenediphosphonate as the phosphorus component, the unique chelating nature of the ligand precludes formation of the pentamolybdate core, resulting in the chain structures [[Cu(2)(tpypyz)(H(2)O)]Mo(3)O(8) (HO(3)PCH(2)PO(3))(2)].8H(2)O (3.8H(2)O) and [[Cu(2)(tpypyz)(H(2)O)](2)(Mo(3)O(8))(2)(O(3)PCH(2)PO(3))(3)].16.9H(2)O (4.16.9H(2)O). For structures 1-7, the secondary metal-ligand building block is the binuclear [Cu(2)(tpypyz)(H(2)O)(x)](4+) cluster. There is considerable structural versatility as a result of the variability in the number of attachment sites at the phosphomolybdate clusters, the coordination geometry of the Cu(II), which may be four-, five-, or six-coordinate, the extent of aqua ligation, and the participation of phosphate oxygen atoms as well as molybdate oxo groups in bonding to the copper sites. Crystal data: 1.H(2)O, C(26)H(28)N(6)Cu(2)Mo(5)O(28)P(2), monoclinic C2/c, a = 42.497(2) A, b = 10.7421(4) A, c = 20.5617(8) A, beta = 117.178(1) degrees, V = 8350.1(5) A(3), Z = 8; 2.2H(2)O, C(36)H(32)N(6)Cu(2)Mo(5)O(24)P(2), monoclinic P2(1)/c, a = 11.2478(7) A, b = 19.513(1) A, c = 21.063(1) A, beta = 93.608(1) degrees, V = 4613.7(5) A(3), Z = 4; 3.8H(2)O, C(26)H(40)N(6)Cu(2)Mo(3)O(29)P(4), monoclinic C2/c, a = 32.580(2) A, b = 17.8676(9) A, c = 15.9612(8) A, beta = 104.430(1) degrees, V = 8993.3(8) A(3), Z = 8; 4.16.9H(2)O, C(51)H(71.75)Cu(4)Mo(6)N(12)O(51)P(6), monoclinic P2(1)/c, a = 27.929(3) A, b = 12.892(2) A, c = 22.763(3) A, beta = 90.367(2) degrees, V = 8195.7(2) A(3), Z = 4;( )()5.2H(2)O, C(24)H(28)N(6)Cu(2)Mo(5)O(28)P(2), monoclinic P2(1)/n, a = 11.3222(4) A, b = 18.7673(7) A, c = 19.4124(7) A, beta = 98.819(1) degrees, V = 4076.1(3) A(3), Z = 4; 6.2.25H(2)O, C(27)H(28.5)N(6)Cu(2)Mo(5)O(24.25)P(2), monoclinic C2/c, a = 12.8366(5) A, b = 18.4221(8) A, c = 34.326(1) A, beta = 100.546(1) degrees, V = 7980.1(6) A(3), Z = 8; 7.(1)/(3)H(2)O, C(28)H(28.7)N(6)Cu(2)Mo(5)O(23.3)P(2), monoclinic C2/c, a = 12.577(1) A, b = 18.336(1) A, c = 36.476(3) A, beta = 91.929(2) degrees, V = 8407.3 A(3), Z = 8.     

Diverse solid-state and solution structures within a series of hexaamine dicopper(II) complexes

Mono- and dicopper(II) complexes of a series of potentially bridging hexaamine ligands have been prepared and characterized in the solid state by X-ray crystallography. The crystal structures of the following Cu(II) complexes are reported: [Cu(HL3)](ClO4)(3), C11H31Cl3CuN6O12, monoclinic, P2(1)/n, a = 8.294(2) A, b = 18.364(3) A, c = 15.674(3) A, beta = 94.73(2) degrees, Z = 4; ([Cu2(L4)(CO3)](2))(ClO4)(4).4H2O, C40H100Cl4Cu4N12O26, triclinic, P1, a = 9.4888(8) A, b = 13.353(1) A, c = 15.329(1) A, alpha = 111.250(7) degrees, beta = 90.068(8) degrees, gamma = 105.081(8) degrees, Z = 1; [Cu2(L5)(OH2)(2)](ClO4)(4), C13H36Cl4Cu2N6O18, monoclinic, P2(1)/c, a = 7.225(2) A, b = 8.5555(5) A, c = 23.134(8) A, beta = 92.37(1) degrees, Z = 2; [Cu2(L6)(OH2)(2)](ClO4)(4).3H2O, C14H44Cl4Cu2N6O21, monoclinic, P2(1)/a, a = 15.204(5) A, b = 7.6810(7) A, c = 29.370(1) A, beta = 100.42(2) degrees, Z = 4. Solution spectroscopic properties of the bimetallic complexes indicate that significant conformational changes occur upon dissolution, and this has been probed with EPR spectroscopy and molecular mechanics calculations.     

Two versatile N,N'-bipyridine-type ligands for preparing organic-inorganic coordination polymers: new cobalt- and nickel-containing framework materials

The Schiff base ligands 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene (L1, monoclinic, P2(1)/c, a = 3.856(1) A, b = 11.032(2) A, c = 12.738(3) A, beta = 92.21(3) degrees, Z = 2) and 2,5-bis(4-pyridyl)-3,4-diaza-2,4-hexadiene (L2, monoclinic, P2(1)/c, a = 10.885(2) A, b = 4.613(1) A, c = 14.978(3) A, beta = 92.827(4) degrees, Z = 2) were used in the synthesis of four new organic-inorganic coordination polymers, each of them adopting a different structural motif. Synthesis, X-ray structural determinations, and spectroscopic and thermogravimetric analyses are presented. The reaction between Co(NO(3))(2).6H(2)O and L1 afforded a two-dimensional noninterpenetrating brick-wall structure, [Co(C(12)N(4)H(10))(1.5)(NO(3))(2)(H(2)O)(CH(2)Cl(2))(2)](n)() (1, triclinic, P1; a = 10.242(7) A, b = 10.802(7) A, c = 15.100(1) A, alpha = 70.031(1), beta = 75.168(11), gamma = 76.155(11), Z = 2), while Ni(NO(3))(2).6H(2)O combined with L1 yielded an interpenetrating three-dimensional rhombus-grid polymer, [Ni(C(12)N(4)H(10))(2)(NO(3))(2)(OC(4)H(8))(1.66)(H(2)O)(0.33)](n) (2, monoclinic, C2/c; a = 20.815(8) A, b = 23.427(8) A, c = 17.291(6) A, beta = 116.148(6), Z = 8). The reaction of Co(NO(3))(2).6H(2)O and L2 was found to be solvent-sensitive and resulted in the formation of two different noninterpenetrating compounds: [Co(C(14)N(4)H(14))(2)(NO(3))(2)(C(6)H(6))(1.5)](n)() (3, monoclinic, C2/c; a = 22.760(2) A, b = 21.010(3) A, c = 25.521(2) A, beta = 97.151(2), Z = 8), which adopts a two-dimensional square-grid motif formed by propeller-type modules, and [Co(C(14)N(4)H(14))(1.5)(NO(3))(2)(CH(2)Cl(2))(2)](n)() (4, monoclinic, P2(1)/n; a = 14.432(2) A, b = 14.543(8) A, c = 15.448(4) A, beta = 96.968(0), Z = 4), consisting of T-shaped building blocks assembled into a one-dimensional ladder-type structure. These four coordination polymers all exhibit impressive thermal stability. Thermogravimetric studies showed that after complete removal of the solvents, the frameworks are stable to temperatures between 234 degrees C and 260 degrees C.     

First Cu(II) diamondoid net with 2-fold interpenetrating frameworks. The role of anions in the construction of the supramolecular arrays

The synthesis and crystal structure of the three-dimensional coordination polymer of an angular dipyridyl ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (L) and Cu(ClO(4))(2), exhibiting the first Cu(II) diamondoid network with 2-fold interpenetration, ([Cu(L)(2)(H(2)O)(2)](ClO(4))(OH)(H(2)O)(2.5))(n) (1), together with the Cu(OAc)(2) complex of L, [Cu(L)(2)(OAc)(2)(H(2)O)](H(2)O)(2)(CH(3)OH) (2), with an unexpected mononuclear structure, are reported. Crystal data for 1: tetragonal, space group I4(1)/a, a = b = 13.477(3) A, c = 46.167(13) A, Z = 8. Crystal data for 2: triclinic, space group P(-)1, a = 7.847(2) A, b = 13.189(4) A, c = 15.948(5) A, alpha = 75.225(7) degrees, beta = 79.945(6) degrees, gamma = 77.540(5) degrees, Z = 2. The magnetic properties and anion effect are also discussed.     

Ligand design for alkali-metal-templated self-assembly of unique high-nuclearity CuII aggregates with diverse coordination cage units: crystal structures and properties

The construction of two unique, high-nuclearity Cu(II) supramolecular aggregates with tetrahedral or octahedral cage units, [(mu(3)-Cl)[Li subset Cu(4)(mu-L(1))(3)](3)](ClO(4))(8)(H(2)O)(4.5) (1) and [[Na(2) subset Cu(12)(mu-L(2))(8)(mu-Cl)(4)](ClO(4))(8)(H(2)O)(10)(H(3)O(+))(2)](infinity) (2) by alkali-metal-templated (Li(+) or Na(+)) self-assembly, was achieved by the use of two newly designed carboxylic-functionalized diazamesocyclic ligands, N,N'-bis(3-propionyloxy)-1,4-diazacycloheptane (H(2)L(1)) or 1,5-diazacyclooctane-N,N'-diacetate acid (H(2)L(2)). Complex 1 crystallizes in the trigonal R3c space group (a = b = 20.866(3), c = 126.26(4) A and Z = 12), and 2 in the triclinic P1 space group (a = 13.632(4), b = 14.754(4), c = 19.517(6) A, alpha = 99.836(6), beta = 95.793(5), gamma = 116.124(5) degrees and Z = 1). By subtle variation of the ligand structures and the alkali-metal templates, different polymeric motifs were obtained: a dodecanuclear architecture 1 consisting of three Cu(4) tetrahedral cage units with a Li(+) template, and a supramolecular chain 2 consisting of two crystallographically nonequivalent octahedral Cu(6) polyhedra with a Na(+) template. The effects of ligand functionality and alkali metal template ions on the self-assembly processes of both coordination supramolecular aggregates, and their magnetic behaviors are discussed in detail.     

Di- and tetra-nuclear copper(II), nickel(II), and cobalt(II) complexes of four bis-tetradentate triazole-based ligands: synthesis, structure, and magnetic properties

Four bis-tetradentate N(4)-substituted-3,5-{bis[bis-N-(2-pyridinemethyl)]aminomethyl}-4H-1,2,4-triazole ligands, L(Tz1)-L(Tz4), differing only in the triazole N(4) substituent R (where R is amino, pyrrolyl, phenyl, or 4-tertbutylphenyl, respectively) have been synthesized, characterized, and reacted with M(II)(BF(4))(2)·6H(2)O (M(II) = Cu, Ni or Co) and Co(SCN)(2). Experiments using all 16 possible combinations of metal salt and L(TzR) were carried out: 14 pure complexes were obtained, 11 of which are dinuclear, while the other three are tetranuclear. The dinuclear complexes include two copper(II) complexes, [Cu(II)(2)(L(Tz2))(H(2)O)(4)](BF(4))(4) (2), [Cu(II)(2)(L(Tz4))(BF(4))(2)](BF(4))(2) (4); two nickel(II) complexes, [Ni(II)(2)(L(Tz1))(H(2)O)(3)(CH(3)CN)](BF(4))(4)·0.5(CH(3)CN) (5) and [Ni(II)(2)(L(Tz4))(H(2)O)(4)](BF(4))(4)·H(2)O (8); and seven cobalt(II) complexes, [Co(II)(2)(L(Tz1))(μ-BF(4))](BF(4))(3)·H(2)O (9), [Co(II)(2)(L(Tz2))(μ-BF(4))](BF(4))(3)·2H(2)O (10), [Co(II)(2)(L(Tz3))(H(2)O)(2)](BF(4))(4) (11), [Co(II)(2)(L(Tz4))(μ-BF(4))](BF(4))(3)·3H(2)O (12), [Co(II)(2)(L(Tz1))(SCN)(4)]·3H(2)O (13), [Co(II)(2)(L(Tz2))(SCN)(4)]·2H(2)O (14), and [Co(II)(2)(L(Tz3))(SCN)(4)]·H(2)O (15). The tetranuclear complexes are [Cu(II)(4)(L(Tz1))(2)(H(2)O)(2)(BF(4))(2)](BF(4))(6) (1), [Cu(II)(4)(L(Tz3))(2)(H(2)O)(2)(μ-F)(2)](BF(4))(6)·0.5H(2)O (3), and [Ni(II)(4)(L(Tz3))(2)(H(2)O)(4)(μ-F(2))](BF(4))(6)·6.5H(2)O (7). Single crystal X-ray structure determinations revealed different solvent content from that found by microanalysis of the bulk sample after drying under a vacuum and confirmed that 5', 8', 9', 11', 12', and 15' are dinuclear while 1' and 7' are tetranuclear. As expected, magnetic measurements showed that weak antiferromagnetic intracomplex interactions are present in 1, 2, 4, 7, and 8, stabilizing a singlet spin ground state. All seven of the dinuclear cobalt(II) complexes, 9-15, have similar magnetic behavior and remain in the [HS-HS] state between 300 and 1.8 K.     

Coordination-position isomeric M(II)Cu(II) and Cu(II)M(II) (M = Co, Ni, Zn) complexes derived from macrocyclic compartmental ligands

The dinucleating macrocyclic ligands (L(2;2))(2-) and (L(2;3))(2-), comprised of two 2-[(N-methylamino)methyl]-6-(iminomethyl)-4-bromophenolate entities combined by the -(CH(2))(2)- chain between the two aminic nitrogen atoms and by the -(CH(2))(2)- or -(CH(2))(3)- chain between the two iminic nitrogen atoms, have afforded the following M(II)Cu(II) complexes: [CoCu(L(2;2))](ClO(4))(2).MeCN (1A), [NiCu(L(2;2))](ClO(4))(2) (2A), [ZnCu(L(2;2))](ClO(4))(2).0.5MeCN.EtOH (3A), [CoCu(L(2;3))(MeCN)(2-PrOH)](ClO(4))(2) (4A), [NiCu(L(2;3))](ClO(4))(2) (5A), and [ZnCu(L(2;3))](ClO(4))(2).1.5DMF (6A). [CoCu(L(2;2))(MeCN)(3)](ClO(4))(2) (1A') crystallizes in the monoclinic space group P2(1)/n, a = 11.691(2) A, b = 18.572(3) A, c = 17.058(3) A, beta= 91.18(2) degrees, V = 3703(1) A(3), and Z = 4. [NiCu(L(2;2))(DMF)(2)](ClO(4))(2) (2A') crystallizes in the triclinic space group P(-)1, a = 11.260(2) A, b = 16.359(6) A, c = 10.853(4) A, alpha= 96.98(3) degrees, beta= 91.18(2) degrees, gamma= 75.20(2) degrees, V = 1917(1) A(3), and Z = 2. 4A crystallizes in the monoclinic space group P2(1)/c, a = 15.064(8) A, b = 11.434(5) A, c = 21.352(5) A, beta= 95.83(2)degrees, V = 3659(2) A(3), and Z = 4. The X-ray crystallographic results demonstrate the M(II) to reside in the N(amine)(2)O(2) site and the Cu(II) in the N(imine)(2)O(2) site. The complexes 1-6 are regarded to be isomeric with [CuCo(L(2;2)))](ClO(4))(2).DMF (1B), [CuNi(L(2;2)))](ClO(4))(2).DMF.MeOH (2B), [CuZn(L(2;2)))](ClO(4))(2).H(2)O (3B)), [CuCo(L(2;3)))](ClO(4))(2).2H(2)O (4B), [CuNi(L(2;3)))](ClO(4))(2) (5B), and [CuZn(L(2;3)))](ClO(4))(2).H(2)O (6B) reported previously, when we ignore exogenous donating and solvating molecules. The isomeric M(II)Cu(II) and Cu(II)M(II) complexes are differentiated by X-ray structural, magnetic, visible spectroscopic, and electrochemical studies. The two isomeric forms are significantly stabilized by the "macrocyclic effect" of the ligands, but 1A is converted into 1B on an electrode, and 2A is converted into 2B at elevated temperature.     

Macrocyclic copper(II) and zinc(II) complexes incorporating phosphate esters

Slow evaporation of solutions prepared by adding either Cu(ClO(4))(2).6H(2)O or Zn(ClO(4))(2).6H(2)O to solutions containing appropriate proportions of Me(3)tacn (1,4,7-trimethyl-1,4,7-triazacyclononane) and sodium phenyl phosphate (Na(2)PhOPO(3)) gave dark blue crystals of [Cu(3)(Me(3)tacn)(3)(PhOPO(3))(2)](ClO(4))(2).(1)/(2)H(2)O (1) and colorless crystals of [Zn(2)(Me(3)tacn)(2)(H(2)O)(4)(PhOPO(3))](ClO(4))(2).H(2)O (2), respectively. Blue crystals of [Cu(tacn)(2)](BNPP)(2) (3) formed in an aqueous solution of [Cu(tacn)Cl(2)], bis(p-nitrophenyl phosphate) (BNPP), and HEPES buffer (pH 7.4). Compound 1 crystallizes in the triclinic space group P1 (No. 2) with a = 9.8053(2) A, b = 12.9068(2) A, c = 22.1132(2) A, alpha = 98.636(1) degrees, beta = 99.546(1) degrees, gamma = 101.1733(8) degrees, and Z = 2 and exhibits trinuclear Cu(II) clusters in which square pyramidal metal centers are capped by two phosphate esters located above and below the plane of the metal centers. The trinuclear cluster is asymmetric having Cu...Cu distances of 4.14, 4.55, and 5.04 A. Compound 2 crystallizes in the monoclinic space group P2(1)/c (No. 14) with a = 13.6248(2) A, b = 11.6002(2) A, c = 25.9681(4) A, beta = 102.0072(9) degrees, and Z = 4 and contains a dinuclear Zn(II) complex formed by linking two units of [Zn(Me(3)tacn)(OH(2))(2)](2+) by a single phosphate ester. Compound 3 crystallizes in the monoclinic space group C2/c (No. 15) with a = 24.7105(5) A, b = 12.8627(3) A, c = 14.0079(3) A, beta = 106.600(1) degrees, and Z = 4 and consists of mononuclear [Cu(tacn)(2)](2+) cations whose charge is balanced by the BNPP(-) anions.     

Self-assembly of cuII and niII [2 x 2] grid complexes and a binuclear CuII complex with a new semiflexible substituted pyrazine ligand: multiple anion encapsulation and magnetic properties

With the new substituted pyrazine ligand pyrazine-2,3-dicarboxylic acid bis[(pyridin-2-ylmethyl)amide], H(2)L, a binuclear complex [Cu(2)(LH)(Cl(3))(H(2)O)].H(2)O (1) and two [2 x 2]G grid complexes, [[Cu(4)(LH)(4)](ClO(4))(4)].5CH(3)OH.4H(2)O (2) and [[Ni(4)(LH)(4)]Cl(4)].5CH(3)CN.13H(2)O (3), have been synthesized and characterized spectroscopically and crystallographically. The ligand H(2)L crystallized in the triclinic space group P1, with a = 4.9882(7) A, b = 12.079(2) A, c = 14.454(2) A, alpha = 107.08(2) degrees, beta = 98.61(2) degrees, gamma = 97.54(2) degrees, V = 808.8(2) A(3), Z = 2, R1 = 0.0747, and R(w) = 0.1829 for 1319 observed reflections [I > 2 sigma(I)]. The molecule is L-shaped with a strong intramolecular bifurcated hydrogen bond in half of the molecule. In the crystal the molecules are linked by an intermolecular hydrogen bond to form a 1D polymer. The binuclear complex [Cu(2)(LH)(Cl(3))(H(2)O)].H(2)O (1) crystallized in the monoclinic space group P2(1)/a, with a = 8.6859(7) A, b = 28.060(2) A, c = 9.5334(9) A, beta = 107.89(1) degrees, V = 2211.2(3) A(3), Z = 4, R1 = 0.039, and R(w) = 0.097 for 1408 observed reflections [I > 2 sigma(I)]. There are two independent copper atoms both having square pyramidal geometry. Both coordinate to a pyrazine, a pyridine, and an amide N atom. Two chlorines complete the coordination sphere of one of the copper atoms, while one chlorine atom and a water molecule complete the coordination sphere of the other. The copper(II) [2 x 2] grid complex [[Cu(4)(LH)(4)](ClO(4))(4)].5CH(3)OH.4H(2)O (2) crystallized in the triclinic space group P1, with a = 17.1515(14) A, b = 17.7507(13) A, c = 19.3333(15) A, alpha = 67.34(1) degrees, beta = 69.79(1) degrees, gamma = 71.50(1) degrees, V = 4980.3(7) A(3), Z = 2, R1 = 0.083, and R(w) = 0.207 for 5532 observed reflections [I > 2 sigma(I)]. The four Cu(II) atoms are octahedrally coordinated by two pyrazine, two pyridine, and two amide N atoms and occupy the corners of a [2 x 2] grid with edge lengths, Cu...Cu, varying from 7.01 to 7.39 A. The nickel(II) [2 x 2] grid complex [[Ni(4)(LH)(4)]Cl(4)].5CH(3)CN.13H(2)O (3) crystallized in the monoclinic space group C2/c, with a = 16.3388(10) A, b = 29.754(2) A, c = 20.857(1) A, beta = 101.845(1) degrees, V = 9923.6(12) A(3), Z = 4, R1 = 0.050, and wR2 = 0.101 for 3391 observed reflections [I > 2 sigma(I)]. Here the complex possesses C(2) symmetry and again each metal atom is octahedrally coordinated to two pyrazine, two pyridine, and two amide N atoms. They occupy the corners of a [2 x 2] grid with an average edge length, Ni.Ni, of 6.97 A. Of the four anions (ClO(4)(-)'s in 2 and Cl(-)'s in 3) required to equilibrate the charges in the grid complexes, two are encapsulated, one above and one below the plane of the four metal atoms. The remaining two anions are located between the "wings" of the ligands. Magnetic susceptibility measurements indicate that the binuclear complex 1 is antiferromagnetic, with a J value of -15.07 cm(-1). This is larger than the J values found for the Cu(II) (2) and Ni(II) (3) grid complexes, which were -5.87 and -2.64 cm(-1), respectively. DFT calculations have been carried out to explain the difference in the J values found for complexes 1 and 2.     

New mononuclear, cyclic tetranuclear, and 1-D helical-chain Cu(II) complexes formed by metal-assisted hydrolysis of 3,6-di-2-pyridyl-1,2,4,5-tetrazine (DPTZ): crystal structures and magnetic properties

The reactions of 3,6-di-2-pyridyl-1,2,4,5-tetrazine (DPTZ) with different Cu(II) salts generate two new ligands, 2,5-bis(2-pyridyl)-1,3,4-oxodiazole (L(1)) and N,N'-bis(alpha-hydroxyl-2-pyridyl)ketazine (H(2)L(2)), from the metal-assisted hydrolysis of DPTZ, and form three new complexes: a mononuclear complex [Cu(L(1))(2)(H(2)O)(2)] .2ClO(4) (1), a linear coordination polymer [Cu(L(1))(NO(3))(2)](8) (2), and a cyclic tetranuclear complex [Cu(4)(L(2))(2)(Im)(2)(NO(3))(4)(H(2)O)(2)] (3) (Im = imidazole). Crystal data for 1: space group P2(1)/n with a = 10.339(3) A, b = 10.974(2) A, c = 13.618(4) A, beta = 103.24(1) degrees, and Z = 2. Crystal data for 2: space group C2/c with a = 13.9299(14) A, b = 9.2275(9) A, c = 12.1865(13) A, beta = 111.248(2) degrees, and Z = 4. Crystal data for 3: space group P2(1)/n with a = 9.3422(14) A, b = 15.987(2) A, c = 13.963(2) A, beta = 108.587(3) degrees, and Z = 2. L(1) acts as a bidentate chelating ligand in 1 and as a bis-bidentate chelating ligand in 2 with the shortest intramolecular Cu...Cu distance of 6.093 A. L(2) is a hexadentate ligand to bridge four Cu(II) ions, forming an interesting neutral cyclic tetranuclear complex 3 with Cu...Cu distances varying from 4.484 to 9.370 A. The mechanism of the metal assisted hydrolysis of DPTZ is discussed in detail. Magnetic susceptibility measurements indicate that 2 shows weak ferromagnetic interaction (J = 2.85 cm(-1)) along the 1-D helical chain, and that 3 displays weak antiferromagnetic interaction (J = -1.19 cm(-1) for the N-N bridge) and ferromagnetic interaction (j = 0.11 cm(-1) for the O-C=N bridge) between the adjacent Cu(II) ions.     

Supramolecular Mn(II) and Mn(II)/Mn(III) grid complexes with [Mn9(mu2-O)12] core structures. Structural, magnetic, and redox properties and surface studies

A series of [3 x 3] Mn(II)(9), antiferromagnetically coupled, alkoxide-bridged, square grid complexes, derived from a group of "tritopic" dihydrazide ligands, is described. The outer ring of eight Mn(II) centers in the grids is isolated magnetically from the central Mn(II) ion, leading to an S = 0 ground state for the ring, and an S = 5/2 ground state overall in each case. Exchange in the Mn(II)(8) ring can be represented by a 1D chain exchange model. Rich electrochemistry displayed by these systems has led to the production of Mn(II)/Mn(III) mixed-oxidation-state grids by both electrochemical and chemical means. Structures are reported for [Mn(9)(2poap)(6)](C(2)N(3))(6).10H(2)O (1), [Mn(9)(2poap)(6)](2)[Mn(NCS)(4)(H(2)O)](2)(NCS)(8).10H(2)O (2), [Mn(9)(2poapz)(6)](NO(3))(6).14.5H(2)O (3), [Mn(9)(2popp)(6)](NO(3))(6).12H(2)O (4), [Mn(9)(2pomp)(6)](MnCl(4))(2)Cl(2).2CH(3)OH.7H(2)O (5), and [Mn(9)(Cl2poap)(6)](ClO(4))(9).7H(2)O (6). Compound 1 crystallized in the tetragonal system, space group P4(2)/n, with a = 21.568(1) A, c = 16.275(1) A, and Z = 2. Compound 2 crystallized in the triclinic system, space group P, with a = 25.043(1) A, b = 27.413(1) A, c = 27.538(2) A, alpha = 91.586(2) degrees, beta = 113.9200(9) degrees, gamma = 111.9470(8) degrees, and Z = 2. Compound 3 crystallized in the triclinic system, space group P, with a = 18.1578(12) A, b = 18.2887(12) A, c = 26.764(2) A, alpha = 105.7880(12) degrees, beta = 101.547(2) degrees, gamma = 91.1250(11) degrees, and Z = 2. Compound 4 crystallized in the tetragonal system, space group P4(1)2(1)2, with a = 20.279(1) A, c = 54.873(6) A, and Z = 4. Compound 5 crystallized in the tetragonal system, space group I, with a = 18.2700(2) A, c = 26.753(2) A, and Z = 2. Compound 6 crystallized in the triclinic system, space group P, with a = 19.044(2) A, b = 19.457(2) A, c = 23.978(3) A, alpha = 84.518(3) degrees, beta = 81.227(3) degrees, gamma = 60.954(2) degrees, and Z = 2. Preliminary surface studies on Au(111), with a Mn(II) grid complex derived from a sulfur-derivatized ligand, indicate monolayer coverage via gold-sulfur interactions, and the potential for information storage at high-density levels.     

Self-assembled dinuclear,trinuclear, tetranuclear,pentanuclear, and octanuclear Ni(II) complexes of a series of polytopic diazine based ligands: structural and magnetic properties

The nickel coordination chemistry of a series of polytopic diazine (N-N) based ligands has been examined. Self-assembly reactions lead to examples of dinuclear, trinuclear, tetranuclear, pentanuclear, and octanuclear complexes, all of which exhibit magnetic exchange coupling, with antiferromagnetic and ferromagnetic examples. Structural details are presented for [(L1)(2)Ni(2)(H(2)O)(2)](NO(3))(4).3H(2)O (1), [(L2)(2)Ni(3)(H(2)O)(2)](NO(3))(6).8H(2)O (2), [(L3)(4)Ni(4)(H(2)O)(8)] (NO(3))(4).8H(2)O (3), [(L4)(2)Ni(5)(H(2)O)(10)(NO(3))](NO(3))(7).8H(2)O (4), and [(L5)(4)Ni(8)(H(2)O)(8)](BF(4))(8).16H(2)O (5). Compound 1 crystallizes in the monoclinic system, space group P2(1)/c, with a = 14.937(1) A, b = 18.612(2) A, c = 20.583(2) A, beta = 108.862(2) degrees, Z = 4. Compound 2 crystallizes in the orthorhombic system, space group P2(1)2(1)2, with a = 21.771(4) A, b = 13.700(2) A, c = 20.017(3) A, Z = 4. Compound 3 crystallizes in the tetragonal system, space group P4(3), with a = 12.9483(7) A, c = 33.416(3) A, Z = 4. Compound 4 crystallizes in the triclinic system, space group P(-)1, with a = 12.6677(8) A, b = 18.110(1) A, c = 19.998(1) A, alpha = 100.395(1) degrees, beta = 109.514(1) degrees, gamma = 109.686(1) degrees, Z = 2. Compound 5 crystallizes in the monoclinic system, space group P2(1)/n, with a = 21.153(5) A, b = 35.778(9) A, c = 21.823(5) A, beta = 97.757(6) degrees, Z = 4. The linear trinuclear Ni(II) complex (2) has a cis-N-N single bond bridge, and a water bridge linking the central Ni(II) to each external Ni(II) center in each of two similar trinuclear subunits, and exhibits intramolecular ferromagnetic exchange (J = 5.0 cm(-1)). A novel octanuclear metallacyclic ring structure exists in 5, with trans-N-N single bond bridges linking adjacent Ni(II) centers, leading to quite strong intramolecular antiferromagnetic exchange (J = -30.4 cm(-1)).     

Hydrothermal synthesis,structures, and magnetic properties of three novel 5-aminoisophthalic acid ligand bridged transition metal cation polymers

Three novel 5-aminoisophthalic acid (AIP) bridged polymers [Co(C(8)NH(5)O(4))(H(2)O)](n)() (1), [Ni(C(8)NH(5)O(4))(H(2)O)(2)](n)() (2), and [Zn(C(8)NH(5)O(4))(H(2)O)](n)() (3) were synthesized by hydrothermal reactions and characterized by IR, Raman, elemental analysis, ESR, and magnetic measurements. X-ray single-crystal analyses were carried out for [Co(C(8)NH(5)O(4))(H(2)O)](n)() (1), which crystallizes in the triclinic system, space group P1 macro, with a = 6.477(1) A, b = 7.130(1) A, c = 9.826(2) A, alpha = 108.9(1) degrees, beta = 93.97(3) degrees, gamma = 98.82(3) degrees, and Z = 2; for [Ni(C(8)NH(5)O(4))(H(2)O)(2)](n)() (2), in the triclinic system, space group P1 macro, a = 6.425(1) A, b = 8.115(2) A, c = 10.146(2) A, alpha = 113.09(3)(o), beta = 99.64(3)(o), gamma = 98.90(3)(o), and Z = 2; and for [Zn(C(8)NH(5)O(4))(H(2)O)](n)() (3), in the monoclinic system, space group P2(1)/n, a = 9.044(1) A, b = 8.264(1) A, c = 11.646(1) A, beta = 100.77(1) degrees, and Z = 4. The single X-ray diffraction studies reveal that 1 consists of an infinite honeycomb layer formed by four crystallographically independent motifs packed alternatively together; 2 consists of an infinite neutral railroad-like linear polymer, and 3 consists of infinite layers of alternating four-coordinated Zn(II) cations and AIP ligands. Finally, they are all packed into beautiful three-dimensional frameworks through complicated hydrogen bonding. Antiferromagnetic and ferromagnetic behaviors were observed for 1 and 2 from the magnetic measurements.     

Synthesis, characterization and magnetic properties of four new organically templated metal sulfates [C5H14N2][M(II)(H2O)6](SO4)2, (M(II) = Mn, Fe, Co, Ni)

A series of novel organically templated metal sulfates, [C(5)H(14)N(2)][M(II)(H(2)O)(6)](SO(4))(2) with (M(II) = Mn (1), Fe (2), Co (3) and Ni (4)), have been successfully synthesized by slow evaporation and characterized by single-crystal X-ray diffraction as well as with infrared spectroscopy, thermogravimetric analysis and magnetic measurements. All compounds were prepared using a racemic source of the 2-methylpiperazine and they crystallized in the monoclinic systems, P2(1)/n for (1, 3) and P2(1)/c for (2,4). Crystal data are as follows: [C(5)H(14)N(2)][Mn(H(2)O)(6)](SO(4))(2), a = 6.6385(10) ?, b = 11.0448(2) ?, c = 12.6418(2) ?, β = 101.903(10)°, V = 906.98(3) ?(3), Z = 2; [C(5)H(14)N(2)][Fe(H(2)O)(6)](SO(4))(2), a = 10.9273(2) ?, b = 7.8620(10) ?, c = 11.7845(3) ?, β = 116.733(10)°, V = 904.20(3) ?(3), Z = 2; [C(5)H(14)N(2)][Co(H(2)O)(6)](SO(4))(2), a = 6.5710(2) ?, b = 10.9078(3) ?, c = 12.5518(3) ?, β = 101.547(2)°, V = 881.44(4) ?(3), Z = 2; [C(5)H(14)N(2)][Ni(H(2)O)(6)](SO(4))(2), a = 10.8328(2) ?, b = 7.8443(10) ?, c = 11.6790(2) ?, β = 116.826(10)°, V = 885.63(2) ?(3), Z = 2. The three-dimensional structure networks for these compounds consist of isolated [M(II)(H(2)O)(6)](2+) and [C(5)H(14)N(2)](2+) cations and (SO(4))(2-) anions linked by hydrogen-bonds only. The use of racemic 2-methylpiperazine results in crystallographic disorder of the amines and creation of inversion centers. The magnetic measurements indicate that the Mn complex (1) is paramagnetic, while compounds 2, 3 and 4, (M(II) = Fe, Co, Ni respectively) exhibit single ion anisotropy.     

Syntheses, crystal structures, and magneto-structural correlations of novel Cu(II) complexes containing a planar [Cu(mu-L1)]2 (HL1 = 3-(2-pyridyl)pyrazole) unit: from dinuclear to tetranuclear and then to one-dimensional compounds

Seven new Cu(II) complexes based on a binuclear planar unit [Cu(mu-L(1))](2), [[Cu(mu-L(1))(NO(3))(H(2)O)](2) (1), [Cu(mu-L(1))(HL(1))(ClO(4))](2) (2), [Cu(4)(mu-L(1))(6)(NO(3))(2)] (3), [Cu(4)(mu-L(1))(6)(L(1))(2)] (4), [Cu(4)(mu-L(1))(6)(mu-L(2))](n) (5), [Cu(4)(mu-L(1))(6)(mu-L(3))](n) (6), [[Cu(4)(mu-L(1))(4)(mu-L(4))(2)](H(2)O)(3)](n) (7) (HL(1) = 3-(2-pyridyl)pyrazole, L(2) = 1,8-naphthalenedicarboxylate, L(3) = terephthalate, L(4) = 2,6-pyridinedicarboxylate)}, have been synthesized and characterized by elemental analysis, IR, and X-ray diffraction. In 1 and 2, the Cu(II) centers are linked by deprotonated pyrazolyl groups to form dinuclear structures. 3 and 4 have similar gridlike tetranuclear structures in which two additional deprotonated L(1) ligands bridge two [Cu(mu-L(1))](2) units perpendicularly. 5 and 6 consist of similar one-dimensional (1-D) chains in which gridlike tetranuclear copper(II) units similar to that of 3 are further linked by L(2) or L(3) ligands, respectively. And, in 7, L(4) ligands link [Cu(mu-L(1))](2) binuclear units to form a tetranuclear gridlike structure in chelating/bridging mode and simultaneously bridge the tetranuclear units to form a 1-D chain. The magnetic properties of all complexes were studied by variable-temperature magnetic susceptibility and magnetization measurements. The obtained parameters of J range from -33.1 to -211 cm(-1), indicating very strong antiferromagnetic coupling between Cu(II) ions. The main factor that affects the |J| parameter is the geometry of the Cu(N(2))(2)Cu entity. From the magnetic point of view, 1 and 2 feature "pure" dinuclear, 3 and 5 tetranuclear, and 4, 6, and 7 pseudodinuclear moieties.     

Preparation of acentric porous coordination frameworks from an interpenetrated diamondoid array through anion-exchange procedures: crystal structures and properties

The formation, crystal structures, and properties of a series of three-dimensional (3-D) Cu(II) coordination polymers, [[Cu(L)2(H2O)2](PF6)2(H2O)(1.25)]n (1), [[CuL(N3)2](H2O)(1.5)]n (2), and [[CuL(H2O)(SO4)](H2O)2]n (3), with an angular bridging ligand 2,5-bis(4-pyridyl)-1,3,4-oxadiazole (L) are reported. Complex 1 crystallizes in the tetragonal I4(1)/a space group (a = b = 13.462(2) A, c = 46.47(1) A, Z = 8), complex 2 in the orthorhombic Pna2(1) space group (a = 6.379(2) A, b = 10.060(3) A, c = 27.232(9) A, Z = 4), and complex 3 in the orthorhombic P2(1)2(1)2(1) space group (a = 5.510(2) A, b = 10.576(4) A, c = 28.34(1) A, Z = 4). Different polymeric frameworks are obtained by only varying the counterions. These include the 2-fold interpenetrated diamondoid structure of 1, the acentric alpha-Po network of 2, and the chiral open framework of 3 with (6(3)).(6(9).8) topology. The interesting anion-exchange, porous, and magnetic properties of these coordination supramolecules have been investigated in detail.     

Encapsulation of cyanometalates by a tris-macrocyclic ligand tricopper(II) complex: syntheses, structural variation, and magnetic exchange coupling pathways

The reaction of [M(CN)(6)](3-) (M = Cr(3+), Mn(3+), Fe(3+), Co(3+)) and [M(CN)(8)](4-/3-) (M = Mo(4+/5+), W(4+/5+)) with the trinuclear copper(II) complex of 1,3,5-triazine-2,4,6-triyltris[3-(1,3,5,8,12-pentaazacyclotetradecane)] ([Cu(3)(L)](6+)) leads to partially encapsulated cyanometalates. With hexacyanometalate(III) complexes, [Cu(3)(L)](6+) forms the isostructural host-guest complexes [[[Cu(3)(L)(OH(2))(2)][M(CN)(6)](2)][M(CN)(6)]][M(CN)(6)]30 H(2)O with one bridging, two partially encapsulated, and one isolated [M(CN)(6)](3-) unit. The octacyanometalates of Mo(4+/5+) and W(4+/5+) are encapsulated by two tris-macrocyclic host units. Due to the stability of the +IV oxidation state of Mo and W, only assemblies with [M(CN)(8)](4-) were obtained. The Mo(4+) and W(4+) complexes were crystallized in two different structural forms: [[Cu(3)(L)(OH(2))](2)[Mo(CN)(8)]](NO(3))(8)15 H(2)O with a structural motif that involves isolated spherical [[Cu(3)(L)(OH(2))](2)[M(CN)(8)]](8+) ions and a "string-of-pearls" type of structure [[[Cu(3)(L)](2)[M(CN)(8)]][M(CN)(8)]](NO(3))(4) 20 H(2)O, with [M(CN)(8)](4-) ions that bridge the encapsulated octacyanometalates in a two-dimensional network. The magnetic exchange coupling between the various paramagnetic centers is characterized by temperature-dependent magnetic susceptibility and field-dependent magnetization data. Exchange between the CuCu pairs in the [Cu(3)(L)](6+) "ligand" is weakly antiferromagnetic. Ferromagnetic interactions are observed in the cyanometalate assemblies with Cr(3+), exchange coupling of Mn(3+) and Fe(3+) is very small, and the octacoordinate Mo(4+) and W(4+) systems have a closed-shell ground state.     

Octanuclear and nonanuclear supramolecular copper(II) complexes with linear "tritopic" ligands: structural and magnetic studies

The structures and magnetic properties of self-assembled copper(II) clusters and grids with the "tritopic" ligands 2poap (a), Cl2poap (b), m2poap (c), Cl2pomp (d), and 2pomp (e) are described [ligands derived by reaction of 4-R-2,6-pyridinedicarboxylic hydrazide (R = H, Cl, MeO) with 2-pyridinemethylimidate (a-c, respectively) or 2-acetylpyridine (d, R = Cl; e, R = H)]. Cl2poap and Cl2pomp self-assemble with Cu(NO(3))(2) to form octanuclear "pinwheel" cluster complexes [Cu(8)(Cl2poap-2H)(4)(NO(3))(8)].20H(2)O (1) and [Cu(8)(Cl2pomp-2H)(4)(NO(3))(8)].15H(2)O (2), built on a square [2 x 2] grid with four pendant copper arms, using "mild" reaction conditions. Similar reactions of Cl2pomp and 2pomp with Cu(ClO(4))(2) produce pinwheel clusters [Cu(8)(Cl2pomp-2H)(4)(H(2)O)(8)](ClO(4))(8).7H(2)O (3) and [Cu(8)(2pomp-2H)(4)(H(2)O)(8)](ClO(4))(8) (4), respectively. Heating a solution of 1 in MeOH/H(2)O produces a [3 x 3] nonanuclear square grid complex, [Cu(9)(Cl2poap-H)(3)(Cl2poap-2H)(3)](NO(3))(9).18H(2)O (5), which is also produced by direct reaction of the ligand and metal salt under similar conditions. Reaction of m2poap with Cu(NO(3))(2) produces only the [3 x 3] grid [Cu(9)(m2poap-H)(2)(m2poap-2H)(4)](NO(3))(8).17H(2)O (6) under similar conditions. Mixing the tritopic ligand 2poap with pyridine-2,6-dicarboxylic acid (picd) in the presence of Cu(NO(3))(2) produces a remarkable mixed ligand, nonanuclear grid complex [Cu(9)(2poap-H)(4)(picd-H)(3)(picd-2H)](NO(3))(9).9H(2)O (7), in which aromatic pi-stacking interactions are important in stabilizing the structure. Complexes 1-3 and 5-7 involve single oxygen atom (alkoxide) bridging connections between adjacent copper centers, while complex 4 has an unprecedented mixed micro-(N-N) and micro-O metal ion connectivity. Compound 1 (C(76)H(92)N(44)Cu(8)O(50)Cl(4)) crystallizes in the tetragonal system, space group I, with a = 21.645(1) A, c = 12.950(1) A, and Z = 2. Compound 2 (C(84)H(88)N(36)O(44)Cl(4)Cu(8)) crystallizes in the tetragonal system, space group I, with a = 21.2562(8) A, c = 12.7583(9) A, and Z = 2. Compound 4 (C(84)H(120)N(28)O(66)Cl(8)Cu(8)) crystallizes in the tetragonal system, space group I4(1)/a, with a = 20.7790(4) A, c = 32.561(1) A, and Z = 4. Compound 7(C(104)H(104)N(46)O(56)Cu(9)) crystallizes in the triclinic system, space group P, with a = 15.473(1) A, b = 19.869(2) A, c = 23.083(2) A, alpha = 88.890(2) degrees, beta = 81.511(2) degrees, gamma = 68.607(1) degrees, and Z = 2. All complexes exhibit dominant intramolecular ferromagnetic exchange coupling, resulting from an orthogonal bridging arrangement within each polynuclear structure.     

Syntheses and magneto-structural study of several polynuclear copper(II) complexes derived from 1,3-Bis(dimethylamino)-2-propanolato

The syntheses, structural characterization, and magnetic behavior of the three new polynuclear copper(II) complexes with formulas [Cu(4)(eta(2):mu-CH(3)COO)(2)(mu-OH)(2)(mu-OH(2))(mu-bdmap)(2)](ClO(4))(2).H(2)O (1), [Cu(8)(NCO)(2)(eta(1):mu-NCO)(4)(mu-OH)(2)(mu(3)-OH)(2)(mu-OH(2))(3)(mu-bdmap)(4)](ClO(4))(2)x2H(2)O (2), and [Cu(9)(eta(1):mu-NCO)(8)(mu(3)-OH)(4)(OH(2))(2)(mu-bdmap)(4)](ClO(4))(2).4H(2)O (3), in which bdmapH is 1,3-bis(dimethylamino)-2-propanol, are reported. Tetranuclear complex 1 crystallizes in the triclinic system, space group P, with unit cell parameters a = 12.160(1) A, b = 13.051(1) A, c = 13.235(1) A, alpha = 110.745(1) degrees , beta = 109.683(1) degrees , gamma = 97.014(1), and Z = 2. Octanuclear complex 2 crystallizes in the monoclinic system, space group C2/c, with unit cell parameters a = 26.609(1) A, b = 14.496(1) A, c = 16.652(1) A, beta = 97.814(1) degrees , and Z = 4, and nonanuclear complex 3 crystallizes in the monoclinic system, space group C2/c, with unit cell parameters a = 24.104(1) A, b = 13.542(1) A, c = 24.355(1) A, beta = 109.98(1) degrees , and Z = 4. The magnetic behavior of the three complexes has been checked showing strong antiferromagnetic coupling in all the cases.     

New Cd(II)-, Co(II)-, and Cu(II)-containing coordination polymers synthesized by using the rigid ligand 1,2-bis(3-pyridyl)ethyne (3,3'-DPA)

Four new organic/inorganic coordination polymers, [Cd(C(10)H(8)N(2))(2)(H(2)O)(2)(NO(3))(2)](n)(1), [Co(C(10)H(8)N(2))(H(2)O)NO(3)CH(3)OH](n)(2), [Cu(C(10)H(8)N(2))(CH(3)OH)(NO(3))(2)](n) (3), and [Cu(C(10)H(8)N(2))(hfac)(2)](n)(4), were synthesized by using the rigid ligand 1,2-bis(3-pyridyl)ethyne (3,3'-DPA). Complex 1 crystallizes in space group P2/n: a = 12.462(2) A, b = 9.485(1) A, c = 13.383(2) A, beta = 96.629(2) degrees, V = 1559.6(3) A(3), Z = 4. Complex 2 crystallizes in space group Fddd: a = 9.248(4) A, b = 19.982(7) A, c = 35.093(16) A, V = 6485.0(4) A(3), Z = 8. Complex 3 crystallizes in space group I2/a: a = 18.315(2) A, b = 8.517(1) A, c = 20.494(3) A, beta = 104.042(2) degrees, V = 3101.2(7) A(3), Z = 8. Complex 4 crystallizes in space group P21/c: a = 6.576(1) A, b = 16.189(1) A, c = 11.653(1) A, beta = 91.337(1) degrees, V = 1240.3(2) A(3), Z = 2. The coordination polymers display a variety of structural architectures, ranging from sinusoidal and zigzag chains (1, 3, 4) to two-dimensional channel-type architectures (2). The effects of the orientation of the nitrogen atom in the pyridine rings on the resultant structures are discussed.