research communications
μ2-3-(pyridin-2-yl)-5-[(1,2,4-triazol-1-yl)methyl]-1,2,4-triazolato}bis[aquanitratocopper(II)] dihydrate
of bis{aDepartment of Inorganic Chemistry, Taras Shevchenko National University of Kyiv, 64, Volodymyrska Str., 01033, Kyiv, Ukraine
*Correspondence e-mail: rdoroschuk@ukr.net
The structure of the dinuclear title complex, [Cu2(C10H8N7)2(NO3)2(H2O)2]·2H2O, consists of centrosymmetric dimeric units with a copper–copper separation of 4.0408 (3) Å. The CuII ions in the dimer display a distorted octahedral coordination geometry and are bridged by two triazole rings, forming an approximately planar Cu2N4 core (r.m.s. deviation = 0.049 Å). In the crystal, O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds and π–π interactions link the molecules into a three-dimensional network.
CCDC reference: 1456451
1. Chemical context
The presence in the triazole ring, three donor atoms and the possibility of introducing in the heterocycle substituents of a different nature creates the conditions for target synthesis of complexes with interesting structures and properties. The study of this type of coordination compound is promising since, as a result, a compound can be obtained with useful physical properties such as optical, magnetic or catalytic (Soghomonian et al., 1993; Blake et al., 1999). Another interesting aspect of these compounds is the possibility of their use as functional models of enzymes such as catechol oxidase (Moliner et al., 2001; Klingele et al., 2009; Selmeczi et al., 2003).
2. Structural commentary
The structure of the title complex molecule (Fig. 1) has a crystallographically imposed centre of symmetry, and contains two copper(II) metal atoms doubly bridged by the triazole rings of two deprotonated ligands. Each copper(II) ion is coordinated in a distorted elongated octahedral geometry by one pyridine and three triazole nitrogen atoms forming the equatorial plane, and by the O atoms of a water molecule and a monodentate nitrate anion at the apices. The Cu—N bond lengths involving the bridging triazole ring [mean value 1.9722 (15) Å] are slightly, but significantly, shorter than those involving the pyridine and peripheral triazole rings [Cu1—N4 = 2.0386 (16) and Cu1—N7 = 2.0409 (17) Å]. The inner Cu2N4 core is approximately planar [r.m.s. deviation = 0.049 Å; maximum displacement 0.062 (2) Å for atom N2], with a Cu⋯Cu separation of 4.0408 (3) Å, in good agreement with the values usually observed in μ-triazolyl-bridged complexes (Haasnoot, 2000). The central triazole ring makes dihedral angles of 7.78 (8) and 49.30 (8)°, respectively, with the pyridine and peripheral triazole rings. The six-membered chelate ring Cu1/N5/C7/C8/N6/N7 assumes a boat conformation [puckering parameters: QT = 0.619 (2) Å; θ2 = 88.62 (16)°], while the five-membered Cu1/N2/C1/C2/N4 chelate ring adopts a flattened with the Cu atom as flap [puckering parameters: Q = 0.127 (2) Å; φ = −156.8 (8)°].
3. Supramolecular features
In the crystal, the complex molecules and water molecules of crystallization are linked through O—H⋯O, O—H⋯N and C—H⋯O hydrogen bonds (Table 1), forming a three-dimensional network (Fig. 2). The is further stabilized by π–π stacking interactions with centroid–centroid separations Cg1⋯Cg2ii = 3.8296 (13) Å and Cg3⋯Cg3iii = 3.5372 (10), and perpendicular interplanar distances Cg1⋯Cg2ii = 3.5584 (9) and Cg3⋯Cg3iii = 3.3234 (10) Å [Cg1, Cg2 and Cg3 are the centroids of the N1/C2/N3/C7i/N5i, N4/C2–C6 and N6/N7/C9/N8/C10 rings, respectively; symmetry codes: (i) −x, 1 − y, −z; (ii) −x, −y, −z; (iii) 1 − x, −y, 1 − z].
4. Database survey
The Cambridge Structural Database (CSD Version 5.36 with three updates; Groom & Allen, 2014), returned 45 entries with the triazole bridging fragment Cu–(N–N)2–Cu. The most similar are: diaquabis(μ-3,5-bis(2-pyridyl)-1,2,4-triazolato-N′,N1,N2,N′′)bis(trifluoromethanesulfonato-O)dicopper(II) (Prins et al., 1985), bis[μ-5-(pyridin-2-yl)-3-(1H-1,2,4-triazol-3-yl)-1,2,4-triazolato]diaquadicopper diperchlorate (Zhou et al., 2014), bis[μ3-(pyridin-2-yl)-5-([5-(pyridin-2-yl)-1,2,4-triazol-1-id-3-yl]methyl)-1,2,4-triazol-1-ide]triaquatricopper diperchlorate dihydrate (Gusev et al., 2014) and bis(μ-5-(2-ethoxy-2-oxoethyl)-3-(pyridin-2-yl)-1H-1,2,4-triazolyl)bis(acetonitrile)bis(perchlorato-O)dicopper (Khomenko et al., 2012). Only 10 compounds containing a pyridyl and a methylene moiety, as substituents in the 3- and 5-positions of 1,2,4-triazole, were found (Lin et al., 2013; Gusev et al., 2014 and references therein).
5. Synthesis and crystallization
A water solution of Cu(NO3)2·3H2O (0.25 mmol, 0.0605 g) was added to a hot solution of 2-[5-(1,2,4,)-triazol-1-yl-methyl-1H-(1,2,4)-triazol-3yl]pyridine (0.25 mmol, 0.059 g) in water (7 ml). The transparent blue solution was left to evaporate slowly in the air and after few hours, blue single crystals suitable for X-ray analysis were obtained (yield: 67%).
6. Refinement
Crystal data, data collection and structure . H atoms of water molecules were located from a difference Fourier map and refined freely. All other H atoms were constrained to ride on their parent atoms, with C—H = 0.95–0.99 Å and with Uiso(H) = 1.2Ueq(C).
details are summarized in Table 2
|
Supporting information
CCDC reference: 1456451
https://doi.org/10.1107/S2056989016003479/rz5185sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989016003479/rz5185Isup2.hkl
Data collection: APEX2 (Bruker, 2003); cell
SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).[Cu2(C10H8N7)2(NO3)2(H2O)2]·2H2O | Z = 1 |
Mr = 775.63 | F(000) = 394 |
Triclinic, P1 | Dx = 1.814 Mg m−3 |
a = 8.8421 (2) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 8.8636 (2) Å | Cell parameters from 6116 reflections |
c = 10.5686 (2) Å | θ = 2.5–26.5° |
α = 70.114 (1)° | µ = 1.58 mm−1 |
β = 88.6311 (10)° | T = 173 K |
γ = 66.765 (1)° | Prism, blue |
V = 709.87 (3) Å3 | 0.50 × 0.50 × 0.45 mm |
Bruker APEXII CCD diffractometer | 2711 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.025 |
Absorption correction: multi-scan (SADABS; Bruker, 2003) | θmax = 26.6°, θmin = 2.5° |
Tmin = 0.505, Tmax = 0.536 | h = −8→11 |
8672 measured reflections | k = −11→11 |
2945 independent reflections | l = −13→13 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.027 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.073 | w = 1/[σ2(Fo2) + (0.0387P)2 + 0.4452P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max < 0.001 |
2945 reflections | Δρmax = 0.26 e Å−3 |
233 parameters | Δρmin = −0.57 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Cu1 | 0.11824 (3) | 0.26915 (3) | 0.15525 (2) | 0.01617 (9) | |
N1 | −0.2107 (2) | 0.3725 (2) | 0.34951 (17) | 0.0208 (4) | |
N2 | −0.0714 (2) | 0.3636 (2) | 0.01433 (17) | 0.0166 (3) | |
N3 | −0.3010 (2) | 0.3463 (2) | −0.04965 (17) | 0.0185 (3) | |
N4 | 0.0614 (2) | 0.0562 (2) | 0.20396 (16) | 0.0169 (3) | |
N5 | 0.1657 (2) | 0.4800 (2) | 0.08348 (17) | 0.0169 (3) | |
N6 | 0.3708 (2) | 0.2657 (2) | 0.34195 (17) | 0.0184 (3) | |
N7 | 0.2554 (2) | 0.2013 (2) | 0.33410 (17) | 0.0185 (3) | |
N8 | 0.3280 (2) | 0.1530 (3) | 0.55105 (19) | 0.0291 (4) | |
O1 | −0.1224 (2) | 0.4373 (2) | 0.27750 (19) | 0.0352 (4) | |
O2 | −0.34096 (19) | 0.4721 (2) | 0.38151 (16) | 0.0281 (3) | |
O3 | −0.1751 (2) | 0.2133 (2) | 0.38786 (18) | 0.0361 (4) | |
O4 | 0.3491 (2) | 0.1266 (2) | 0.07991 (19) | 0.0289 (4) | |
H41O | 0.388 (3) | 0.033 (4) | 0.104 (3) | 0.029 (8)* | |
H42O | 0.376 (3) | 0.168 (4) | 0.010 (3) | 0.032 (8)* | |
O5 | 0.5124 (2) | 0.7700 (2) | 0.15015 (19) | 0.0254 (3) | |
H51O | 0.563 (4) | 0.698 (4) | 0.219 (3) | 0.042 (9)* | |
H52O | 0.458 (4) | 0.736 (4) | 0.125 (3) | 0.041 (9)* | |
C1 | −0.1560 (2) | 0.2649 (2) | 0.03218 (19) | 0.0165 (4) | |
C2 | −0.0792 (2) | 0.0862 (2) | 0.13281 (19) | 0.0172 (4) | |
C3 | 0.1479 (3) | −0.1054 (3) | 0.2939 (2) | 0.0207 (4) | |
H3 | 0.2474 | −0.1283 | 0.3438 | 0.025* | |
C4 | 0.0969 (3) | −0.2412 (3) | 0.3170 (2) | 0.0237 (4) | |
H4 | 0.1614 | −0.3551 | 0.3810 | 0.028* | |
C5 | −0.0481 (3) | −0.2088 (3) | 0.2461 (2) | 0.0239 (4) | |
H5 | −0.0858 | −0.2994 | 0.2614 | 0.029* | |
C6 | −0.1384 (3) | −0.0411 (3) | 0.1517 (2) | 0.0221 (4) | |
H6 | −0.2389 | −0.0149 | 0.1013 | 0.027* | |
C7 | 0.3006 (2) | 0.4957 (2) | 0.1186 (2) | 0.0173 (4) | |
C8 | 0.4370 (2) | 0.3469 (3) | 0.2234 (2) | 0.0204 (4) | |
H8A | 0.5019 | 0.2577 | 0.1842 | 0.025* | |
H8B | 0.5126 | 0.3913 | 0.2508 | 0.025* | |
C9 | 0.2342 (3) | 0.1361 (3) | 0.4624 (2) | 0.0227 (4) | |
H9 | 0.1591 | 0.0820 | 0.4898 | 0.027* | |
C10 | 0.4109 (3) | 0.2351 (3) | 0.4713 (2) | 0.0249 (4) | |
H10 | 0.4888 | 0.2679 | 0.5026 | 0.030* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.01744 (14) | 0.01210 (13) | 0.01794 (14) | −0.00721 (9) | −0.00253 (9) | −0.00253 (10) |
N1 | 0.0217 (9) | 0.0206 (8) | 0.0188 (8) | −0.0079 (7) | −0.0028 (7) | −0.0063 (7) |
N2 | 0.0175 (8) | 0.0123 (7) | 0.0186 (8) | −0.0065 (6) | −0.0017 (6) | −0.0031 (6) |
N3 | 0.0192 (8) | 0.0183 (8) | 0.0192 (8) | −0.0098 (7) | 0.0007 (7) | −0.0052 (7) |
N4 | 0.0192 (8) | 0.0149 (7) | 0.0165 (8) | −0.0071 (6) | 0.0009 (6) | −0.0054 (6) |
N5 | 0.0165 (8) | 0.0132 (7) | 0.0183 (8) | −0.0058 (6) | −0.0029 (6) | −0.0027 (6) |
N6 | 0.0178 (8) | 0.0149 (7) | 0.0209 (9) | −0.0071 (6) | −0.0037 (6) | −0.0038 (7) |
N7 | 0.0168 (8) | 0.0169 (8) | 0.0211 (9) | −0.0079 (6) | −0.0007 (6) | −0.0047 (7) |
N8 | 0.0331 (10) | 0.0328 (10) | 0.0214 (9) | −0.0139 (8) | 0.0005 (8) | −0.0090 (8) |
O1 | 0.0337 (9) | 0.0291 (8) | 0.0463 (11) | −0.0184 (7) | 0.0147 (8) | −0.0121 (8) |
O2 | 0.0240 (8) | 0.0294 (8) | 0.0283 (8) | −0.0063 (6) | 0.0038 (6) | −0.0128 (7) |
O3 | 0.0486 (11) | 0.0177 (8) | 0.0398 (10) | −0.0139 (7) | 0.0086 (8) | −0.0074 (7) |
O4 | 0.0316 (9) | 0.0164 (8) | 0.0332 (10) | −0.0058 (7) | 0.0129 (7) | −0.0079 (7) |
O5 | 0.0245 (8) | 0.0180 (7) | 0.0312 (9) | −0.0098 (7) | −0.0023 (7) | −0.0045 (7) |
C1 | 0.0187 (9) | 0.0154 (9) | 0.0170 (9) | −0.0089 (7) | 0.0013 (7) | −0.0053 (7) |
C2 | 0.0197 (9) | 0.0165 (9) | 0.0164 (9) | −0.0077 (7) | 0.0031 (7) | −0.0067 (8) |
C3 | 0.0219 (10) | 0.0172 (9) | 0.0195 (10) | −0.0059 (8) | 0.0000 (8) | −0.0049 (8) |
C4 | 0.0341 (12) | 0.0143 (9) | 0.0185 (10) | −0.0087 (8) | 0.0023 (8) | −0.0025 (8) |
C5 | 0.0361 (12) | 0.0179 (9) | 0.0226 (11) | −0.0162 (9) | 0.0069 (9) | −0.0073 (8) |
C6 | 0.0265 (11) | 0.0212 (10) | 0.0221 (10) | −0.0140 (8) | 0.0015 (8) | −0.0069 (8) |
C7 | 0.0167 (9) | 0.0177 (9) | 0.0179 (10) | −0.0082 (7) | 0.0007 (7) | −0.0056 (8) |
C8 | 0.0168 (9) | 0.0196 (9) | 0.0225 (10) | −0.0090 (8) | −0.0020 (8) | −0.0027 (8) |
C9 | 0.0244 (10) | 0.0204 (10) | 0.0214 (10) | −0.0087 (8) | 0.0019 (8) | −0.0058 (8) |
C10 | 0.0281 (11) | 0.0234 (10) | 0.0226 (11) | −0.0101 (9) | −0.0038 (8) | −0.0079 (9) |
Cu1—N5 | 1.9709 (15) | N8—C9 | 1.349 (3) |
Cu1—N2 | 1.9732 (16) | O4—H41O | 0.71 (3) |
Cu1—N4 | 2.0386 (16) | O4—H42O | 0.79 (3) |
Cu1—N7 | 2.0409 (17) | O5—H51O | 0.78 (3) |
Cu1—O4 | 2.2293 (16) | O5—H52O | 0.76 (3) |
N1—O3 | 1.234 (2) | C1—C2 | 1.463 (3) |
N1—O1 | 1.244 (2) | C2—C6 | 1.376 (3) |
N1—O2 | 1.266 (2) | C3—C4 | 1.391 (3) |
N2—C1 | 1.326 (2) | C3—H3 | 0.9500 |
N2—N5i | 1.356 (2) | C4—C5 | 1.377 (3) |
N3—C7i | 1.342 (2) | C4—H4 | 0.9500 |
N3—C1 | 1.346 (3) | C5—C6 | 1.391 (3) |
N4—C3 | 1.335 (3) | C5—H5 | 0.9500 |
N4—C2 | 1.352 (3) | C6—H6 | 0.9500 |
N5—C7 | 1.329 (2) | C7—N3i | 1.342 (2) |
N5—N2i | 1.356 (2) | C7—C8 | 1.496 (3) |
N6—C10 | 1.328 (3) | C8—H8A | 0.9900 |
N6—N7 | 1.368 (2) | C8—H8B | 0.9900 |
N6—C8 | 1.455 (3) | C9—H9 | 0.9500 |
N7—C9 | 1.321 (3) | C10—H10 | 0.9500 |
N8—C10 | 1.323 (3) | ||
N5—Cu1—N2 | 93.75 (6) | N2—C1—N3 | 113.40 (17) |
N5—Cu1—N4 | 172.58 (6) | N2—C1—C2 | 116.86 (17) |
N2—Cu1—N4 | 80.29 (6) | N3—C1—C2 | 129.72 (17) |
N5—Cu1—N7 | 88.59 (6) | N4—C2—C6 | 122.81 (18) |
N2—Cu1—N7 | 161.96 (7) | N4—C2—C1 | 112.59 (16) |
N4—Cu1—N7 | 98.45 (6) | C6—C2—C1 | 124.57 (18) |
N5—Cu1—O4 | 87.79 (7) | N4—C3—C4 | 122.16 (19) |
N2—Cu1—O4 | 108.72 (7) | N4—C3—H3 | 118.9 |
N4—Cu1—O4 | 89.95 (6) | C4—C3—H3 | 118.9 |
N7—Cu1—O4 | 89.23 (7) | C5—C4—C3 | 119.35 (19) |
O3—N1—O1 | 120.96 (18) | C5—C4—H4 | 120.3 |
O3—N1—O2 | 119.57 (17) | C3—C4—H4 | 120.3 |
O1—N1—O2 | 119.45 (17) | C4—C5—C6 | 118.81 (18) |
C1—N2—N5i | 105.92 (15) | C4—C5—H5 | 120.6 |
C1—N2—Cu1 | 114.60 (13) | C6—C5—H5 | 120.6 |
N5i—N2—Cu1 | 137.73 (12) | C2—C6—C5 | 118.65 (19) |
C7i—N3—C1 | 101.45 (15) | C2—C6—H6 | 120.7 |
C3—N4—C2 | 118.20 (16) | C5—C6—H6 | 120.7 |
C3—N4—Cu1 | 127.56 (14) | N5—C7—N3i | 113.47 (17) |
C2—N4—Cu1 | 114.23 (13) | N5—C7—C8 | 121.54 (17) |
C7—N5—N2i | 105.75 (15) | N3i—C7—C8 | 124.98 (17) |
C7—N5—Cu1 | 126.66 (13) | N6—C8—C7 | 111.03 (16) |
N2i—N5—Cu1 | 127.56 (12) | N6—C8—H8A | 109.4 |
C10—N6—N7 | 108.72 (16) | C7—C8—H8A | 109.4 |
C10—N6—C8 | 128.56 (17) | N6—C8—H8B | 109.4 |
N7—N6—C8 | 122.68 (16) | C7—C8—H8B | 109.4 |
C9—N7—N6 | 102.89 (16) | H8A—C8—H8B | 108.0 |
C9—N7—Cu1 | 132.81 (14) | N7—C9—N8 | 114.40 (19) |
N6—N7—Cu1 | 122.03 (12) | N7—C9—H9 | 122.8 |
C10—N8—C9 | 102.87 (18) | N8—C9—H9 | 122.8 |
Cu1—O4—H41O | 121 (2) | N8—C10—N6 | 111.12 (18) |
Cu1—O4—H42O | 123 (2) | N8—C10—H10 | 124.4 |
H41O—O4—H42O | 112 (3) | N6—C10—H10 | 124.4 |
H51O—O5—H52O | 107 (3) | ||
C10—N6—N7—C9 | 0.2 (2) | N4—C3—C4—C5 | −0.6 (3) |
C8—N6—N7—C9 | 178.21 (17) | C3—C4—C5—C6 | 0.9 (3) |
C10—N6—N7—Cu1 | 165.14 (14) | N4—C2—C6—C5 | −1.3 (3) |
C8—N6—N7—Cu1 | −16.9 (2) | C1—C2—C6—C5 | 176.53 (18) |
N5i—N2—C1—N3 | 0.8 (2) | C4—C5—C6—C2 | 0.0 (3) |
Cu1—N2—C1—N3 | 168.39 (13) | N2i—N5—C7—N3i | 0.0 (2) |
N5i—N2—C1—C2 | 179.30 (16) | Cu1—N5—C7—N3i | 178.11 (12) |
Cu1—N2—C1—C2 | −13.1 (2) | N2i—N5—C7—C8 | −178.85 (17) |
C7i—N3—C1—N2 | −0.8 (2) | Cu1—N5—C7—C8 | −0.8 (3) |
C7i—N3—C1—C2 | −179.06 (19) | C10—N6—C8—C7 | −127.1 (2) |
C3—N4—C2—C6 | 1.6 (3) | N7—N6—C8—C7 | 55.3 (2) |
Cu1—N4—C2—C6 | −179.68 (15) | N5—C7—C8—N6 | −46.0 (2) |
C3—N4—C2—C1 | −176.44 (16) | N3i—C7—C8—N6 | 135.26 (19) |
Cu1—N4—C2—C1 | 2.2 (2) | N6—N7—C9—N8 | −0.5 (2) |
N2—C1—C2—N4 | 7.0 (2) | Cu1—N7—C9—N8 | −162.96 (15) |
N3—C1—C2—N4 | −174.73 (18) | C10—N8—C9—N7 | 0.5 (2) |
N2—C1—C2—C6 | −171.04 (18) | C9—N8—C10—N6 | −0.3 (2) |
N3—C1—C2—C6 | 7.2 (3) | N7—N6—C10—N8 | 0.1 (2) |
C2—N4—C3—C4 | −0.7 (3) | C8—N6—C10—N8 | −177.76 (18) |
Cu1—N4—C3—C4 | −179.13 (14) |
Symmetry code: (i) −x, −y+1, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O4—H41O···O5ii | 0.71 (3) | 2.03 (3) | 2.735 (2) | 172 (3) |
O4—H42O···O5iii | 0.79 (3) | 1.96 (3) | 2.735 (2) | 168 (3) |
O5—H51O···O2iv | 0.78 (3) | 2.02 (3) | 2.773 (2) | 163 (3) |
O5—H52O···N3i | 0.76 (3) | 2.08 (3) | 2.836 (2) | 177 (3) |
C5—H5···O1ii | 0.95 | 2.43 | 3.360 (3) | 166 |
C8—H8A···O4 | 0.99 | 2.56 | 3.160 (3) | 119 |
C8—H8B···O2iv | 0.99 | 2.36 | 3.319 (3) | 162 |
C9—H9···O3v | 0.95 | 2.44 | 3.205 (3) | 137 |
Symmetry codes: (i) −x, −y+1, −z; (ii) x, y−1, z; (iii) −x+1, −y+1, −z; (iv) x+1, y, z; (v) −x, −y, −z+1. |
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