μ_1,3-Azido-di­azidotetrakis(1,10-phenanthroline)dicopper(II) azide tetra­hydrate

In the title compound, [Cu₂(μ-_1,3-N₃)(N₃)₂(phen)₄](N₃)·4H₂O (phen is 1,10-phenanthroline, C₁₂H₈N₂), each of the two Cu atoms is surrounded by two N atoms of two azide anions and by four N atoms of two 1,10-phenanthroline ligands [Cu—N distances are 1.964 (3), 2.009 (3), 2.018 (3), 2.054 (3), 2.306 (3) and 2.759 (4) Å], forming an elongated CuN₆ octahedron. An ideally linear μ_1,3-azide anion bridges two Cu atoms to form a dimeric structure with the central N atom located on a centre of inversion. Moreover, the adjacent dimeric units are connected by hydrogen-bond interactions to produce one-dimensional chains. A two-dimensional supramolecular array is formed by π–π interactions between the aromatic rings of 1,10-phenanthroline ligands of adjacent dimeric units.

S1. Comment

Studies on the synthesis and properties of bi- and polynuclear complexes bridged by the pseudohalide azide anion (N₃^-) have attracted a lot of attention in recent years (Ribas et al., 1999; Goher et al., 1998; Zhang et al., 2001), owing to their intriguing structural diversity, potential functions as models for metalloenzymes, and ferromagnetic or antiferromagnetic interactions (Baffert et al., 2001; Aebersold et al., 1998; Zhang et al., 2000). The azide anion can bind to metal ions in versatile modes: as a terminal ligand via one nitrogen donor, as a bridge in the µ_1,1 way via one nitrogen donor, and in the µ_1,3 way via both of the peripheral donor N atoms (Sheppard et al., 1996). Despite the fact that a substantial array of copper(II) azido complexes have been synthesized (Goher et al., 1999), to our knowledge, its dimeric single-bridged compounds with 1,10-phenanthroline have not been reported so far. We firstly report here the preparation and crystal structure of a dimeric azido complex of copper(II), namely [Cu₂(phen)₄(m_1,3-azido)(N₃)₂](N₃)·4H₂O (I).

The molecular unit of the title compound comprises a dimeric cation [Cu₂(phen)₄(m_1,3-azido)(N₃)₂]⁺, two azide anions and four water molecules. As shown in Fig. 1, the Cu atom is surrounded by two N atoms of two azide anions and four N atoms of two 1,10-phenanthroline ligands to form a elongated CuN₆ octahedron. The Cu—N bond lengths in apical positions [2.306 (3), 2.759 (4) Å] are much longer than the Cu—N bond lengths in equatorial positions [1.964 (3), 2.009 (3), 2.018 (3), 2.054 (3) Å], due to the Jahn-Teller effects of Cu^II. An ideally linear µ_1,3-azide anion bridges two Cu atoms to form a dimeric entity with N₂ located on a centre of inversion, with the Cu···Cu distance at 6.783 (4) Å.

It should be noted that hydrogen bonding interactions and π-π interactions play an important role in the solid state structure of (I), as shown in Fig. 2. The adjacent dimeric units are connected by hydrogen-bond interactions (O1w···O2w, O1w···N10, O1w···N1, C9···N10I) [2.857 (5), 2.792 (6), 2.908 (5), 3.411 (7) Å], to produce chains. It is interesting that there are interchain π-π interactions between the 1,10-phenanthroline rings of adjacent chains with the face-to-face separation of ca 3.47 Å, which is different from other related compounds (Diaz et al., 2001), resulting in an interesting two-dimensional structure.

S2. Experimental

A mixture of 1.0 mmol of copper(II) nitrate hexahydrate, 2 mmol of 1,10-phenanthroline and 2 mmol sodium azide in 60 ml mixed solvent of water and ethanol(volume 2:1) is stirred for 30 min at room temperature. After four days, dark green crystals of the title compound are obtained in 85% yield.

S3. Refinement

Also, all the H atoms have been constrained and all constrained C—H distances were 0.94 Å.

Computing details

Data collection: SMART1000 (Bruker, 1998); cell refinement: SMART1000; data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1998); software used to prepare material for publication: SHELXL97.

Figures

	Fig. 1. ORTEP (Sheldrick, 1998) plot (50% probability displacement ellipsoids) of the coordination environment in the title compound [Symmetry code: (i) -x, -y, 1 - z].
	Fig. 2. Crystal structure of the title compound (I).

Diazido µ_1,3-azidotetra(1,10-phenanthroline) diCopper(II) azide tetrahydrate

Crystal data

[Cu2(C12H8N2)4(N3)3]·N3·4H2O	Z = 1
Mr = 1088.08	F(000) = 558
Triclinic, P1	Dx = 1.529 Mg m^−3
a = 8.676 (5) Å	Mo Kα radiation, λ = 0.71073 Å
b = 11.843 (8) Å	θ = 1.5–24.3°
c = 12.279 (8) Å	µ = 0.97 mm^−1
α = 80.81 (1)°	T = 293 K
β = 71.74 (1)°	Block, dark green
γ = 84.60 (1)°	0.20 × 0.15 × 0.12 mm
V = 1181.4 (13) Å^3

Data collection

CCD area detector diffractometer	4133 independent reflections
Radiation source: fine-focus sealed tube	3239 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
ω scans	θmax = 25.0°, θmin = 1.7°
Absorption correction: empirical (using intensity measurements) (SADABS; Sheldrick 1996)	h = −9→10
Tmin = 0.858, Tmax = 0.890	k = −14→13
6191 measured reflections	l = −14→12

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.121	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Calculated w = 1/[σ^2(Fo^2) + (0.0587P)^2 + 0.7136P] where P = (Fo^2 + 2Fc^2)/3
4133 reflections	(Δ/σ)max < 0.001
337 parameters	Δρmax = 0.37 e Å^−3
0 restraints	Δρmin = −0.43 e Å^−3

Special details

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Cu1	0.12897 (5)	0.26244 (4)	0.36525 (3)	0.04023 (16)
N1	0.0460 (4)	0.0373 (3)	0.4007 (4)	0.0671 (10)
N2	0.0000	0.0000	0.5000	0.0552 (12)
N3	−0.1025 (4)	0.3100 (3)	0.4176 (3)	0.0519 (8)
N4	−0.1658 (4)	0.3764 (3)	0.3619 (3)	0.0631 (9)
N5	−0.2339 (7)	0.4393 (6)	0.3104 (4)	0.143 (3)
N6	0.1401 (3)	0.2288 (2)	0.5283 (2)	0.0378 (6)
N7	0.3610 (3)	0.1903 (2)	0.3309 (2)	0.0373 (6)
N8	0.2513 (4)	0.4353 (3)	0.3252 (2)	0.0444 (7)
N9	0.1444 (3)	0.3108 (3)	0.1971 (2)	0.0414 (7)
N10	0.1188 (7)	−0.0298 (6)	0.0179 (4)	0.122 (2)
N11	0.0000	0.0000	0.0000	0.0647 (13)
C1	0.0247 (4)	0.2452 (3)	0.6260 (3)	0.0485 (9)
H1A	−0.0821	0.2713	0.6225	0.080*
C2	0.0546 (5)	0.2263 (4)	0.7328 (3)	0.0570 (10)
H2A	−0.0317	0.2387	0.8019	0.080*
C3	0.2056 (5)	0.1903 (4)	0.7385 (3)	0.0540 (10)
H3A	0.2275	0.1768	0.8115	0.080*
C4	0.3316 (4)	0.1724 (3)	0.6369 (3)	0.0410 (8)
C5	0.2910 (4)	0.1926 (3)	0.5339 (3)	0.0346 (7)
C6	0.4114 (4)	0.1739 (3)	0.4268 (3)	0.0362 (7)
C7	0.5701 (4)	0.1392 (3)	0.4262 (3)	0.0417 (8)
C8	0.6827 (4)	0.1209 (3)	0.3181 (3)	0.0511 (9)
H8A	0.7940	0.0989	0.3124	0.080*
C9	0.6312 (5)	0.1356 (3)	0.2223 (4)	0.0568 (10)
H9A	0.7068	0.1222	0.1490	0.080*
C10	0.4690 (4)	0.1699 (3)	0.2317 (3)	0.0478 (9)
H10A	0.4347	0.1794	0.1635	0.080*
C11	0.6092 (4)	0.1214 (3)	0.5328 (4)	0.0500 (9)
H11A	0.7185	0.0980	0.5321	0.080*
C12	0.4942 (5)	0.1366 (3)	0.6333 (3)	0.0486 (9)
H12A	0.5231	0.1235	0.7038	0.080*
C13	0.3111 (5)	0.4915 (3)	0.3864 (4)	0.0535 (10)
H13A	0.2973	0.4614	0.4661	0.080*
C14	0.3920 (5)	0.5926 (4)	0.3411 (4)	0.0611 (11)
H14A	0.4371	0.6297	0.3874	0.080*
C15	0.4093 (5)	0.6377 (4)	0.2294 (4)	0.0635 (11)
H15A	0.4631	0.7082	0.1976	0.080*
C16	0.3453 (4)	0.5814 (3)	0.1606 (3)	0.0509 (9)
C17	0.2696 (4)	0.4784 (3)	0.2130 (3)	0.0411 (8)
C18	0.2102 (4)	0.4137 (3)	0.1462 (3)	0.0414 (8)
C19	0.2197 (4)	0.4579 (3)	0.0306 (3)	0.0500 (9)
C20	0.1561 (5)	0.3930 (4)	−0.0302 (3)	0.0604 (11)
H20A	0.1618	0.4198	−0.1094	0.080*
C21	0.0873 (5)	0.2920 (4)	0.0232 (3)	0.0581 (11)
H21A	0.0408	0.2481	−0.0170	0.080*
C22	0.0854 (4)	0.2528 (4)	0.1366 (3)	0.0487 (9)
H22A	0.0384	0.1809	0.1731	0.080*
C23	0.2941 (5)	0.5659 (4)	−0.0181 (4)	0.0649 (12)
H23A	0.3033	0.5950	−0.0974	0.080*
C24	0.3527 (5)	0.6238 (4)	0.0438 (4)	0.0638 (12)
H24A	0.3996	0.6962	0.0095	0.080*
O1W	0.2627 (4)	−0.0484 (4)	0.1944 (3)	0.0935 (11)
H1WA	0.2658	0.0061	0.1292	0.080*
H1WB	0.2623	−0.0157	0.2594	0.080*
O2W	0.5689 (4)	−0.1273 (3)	0.0509 (3)	0.0857 (10)
H2WA	0.6443	−0.0694	0.0268	0.080*
H2WB	0.4693	−0.1006	0.0989	0.080*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0360 (2)	0.0507 (3)	0.0323 (2)	0.00122 (18)	−0.00952 (17)	−0.00420 (18)
N1	0.056 (2)	0.072 (3)	0.077 (3)	0.0026 (19)	−0.020 (2)	−0.024 (2)
N2	0.033 (2)	0.056 (3)	0.085 (4)	0.008 (2)	−0.024 (3)	−0.030 (3)
N3	0.0397 (17)	0.067 (2)	0.0435 (17)	0.0062 (15)	−0.0103 (14)	−0.0003 (16)
N4	0.054 (2)	0.082 (3)	0.0475 (19)	0.0219 (19)	−0.0130 (17)	−0.0117 (18)
N5	0.128 (5)	0.191 (6)	0.084 (3)	0.094 (4)	−0.036 (3)	0.007 (4)
N6	0.0369 (15)	0.0404 (16)	0.0351 (15)	−0.0008 (12)	−0.0097 (12)	−0.0051 (12)
N7	0.0365 (15)	0.0392 (16)	0.0332 (15)	−0.0031 (12)	−0.0057 (12)	−0.0055 (12)
N8	0.0482 (17)	0.0431 (17)	0.0418 (17)	−0.0021 (13)	−0.0136 (14)	−0.0059 (13)
N9	0.0379 (15)	0.0498 (18)	0.0357 (15)	0.0014 (13)	−0.0111 (12)	−0.0054 (13)
N10	0.088 (4)	0.198 (7)	0.072 (3)	0.020 (4)	−0.022 (3)	−0.016 (3)
N11	0.071 (4)	0.075 (4)	0.042 (3)	0.002 (3)	−0.006 (3)	−0.017 (2)
C1	0.040 (2)	0.060 (2)	0.039 (2)	0.0023 (17)	−0.0048 (16)	−0.0067 (17)
C2	0.056 (2)	0.076 (3)	0.034 (2)	0.006 (2)	−0.0069 (17)	−0.0130 (19)
C3	0.063 (3)	0.064 (3)	0.038 (2)	−0.002 (2)	−0.0195 (18)	−0.0100 (18)
C4	0.048 (2)	0.0357 (19)	0.044 (2)	−0.0021 (15)	−0.0187 (16)	−0.0062 (15)
C5	0.0384 (18)	0.0307 (17)	0.0352 (17)	−0.0040 (13)	−0.0106 (14)	−0.0061 (13)
C6	0.0342 (17)	0.0298 (17)	0.0440 (19)	−0.0029 (13)	−0.0110 (15)	−0.0045 (14)
C7	0.0355 (18)	0.0356 (19)	0.053 (2)	−0.0043 (14)	−0.0114 (16)	−0.0048 (15)
C8	0.038 (2)	0.048 (2)	0.062 (3)	−0.0009 (16)	−0.0087 (18)	−0.0068 (18)
C9	0.049 (2)	0.053 (2)	0.053 (2)	−0.0005 (18)	0.0068 (19)	−0.0087 (19)
C10	0.046 (2)	0.050 (2)	0.042 (2)	−0.0022 (17)	−0.0046 (16)	−0.0062 (16)
C11	0.041 (2)	0.045 (2)	0.071 (3)	−0.0026 (16)	−0.0274 (19)	−0.0080 (19)
C12	0.056 (2)	0.044 (2)	0.055 (2)	−0.0006 (17)	−0.0288 (19)	−0.0082 (17)
C13	0.058 (2)	0.048 (2)	0.056 (2)	0.0011 (19)	−0.0187 (19)	−0.0131 (18)
C14	0.065 (3)	0.050 (2)	0.072 (3)	−0.006 (2)	−0.020 (2)	−0.016 (2)
C15	0.060 (3)	0.043 (2)	0.078 (3)	−0.0114 (19)	−0.007 (2)	−0.005 (2)
C16	0.047 (2)	0.042 (2)	0.052 (2)	0.0039 (17)	−0.0026 (18)	−0.0012 (17)
C17	0.0364 (18)	0.040 (2)	0.0398 (19)	0.0062 (15)	−0.0048 (15)	−0.0048 (15)
C18	0.0326 (17)	0.050 (2)	0.0363 (18)	0.0100 (15)	−0.0070 (14)	−0.0039 (16)
C19	0.044 (2)	0.061 (2)	0.0365 (19)	0.0122 (18)	−0.0080 (16)	0.0009 (17)
C20	0.060 (3)	0.082 (3)	0.036 (2)	0.022 (2)	−0.0153 (19)	−0.009 (2)
C21	0.056 (2)	0.080 (3)	0.043 (2)	0.015 (2)	−0.0188 (19)	−0.024 (2)
C22	0.043 (2)	0.062 (2)	0.044 (2)	0.0039 (17)	−0.0163 (17)	−0.0144 (18)
C23	0.065 (3)	0.066 (3)	0.044 (2)	0.015 (2)	−0.002 (2)	0.010 (2)
C24	0.064 (3)	0.050 (3)	0.060 (3)	−0.001 (2)	−0.004 (2)	0.012 (2)
O1W	0.065 (2)	0.132 (3)	0.088 (2)	0.003 (2)	−0.0223 (19)	−0.037 (2)
O2W	0.076 (2)	0.074 (2)	0.086 (2)	−0.0002 (17)	−0.0029 (18)	0.0050 (18)

Geometric parameters (Å, º)

Cu1—N3	1.964 (3)	C3—C4	1.408 (5)
Cu1—N6	2.009 (3)	C4—C5	1.396 (5)
Cu1—N9	2.018 (3)	C4—C12	1.424 (5)
Cu1—N7	2.054 (3)	C5—C6	1.435 (5)
Cu1—N8	2.306 (3)	C6—C7	1.397 (5)
Cu1—N1	2.759 (4)	C7—C8	1.416 (5)
N1—N2	1.182 (4)	C7—C11	1.431 (5)
N1—O1W	2.908 (5)	C8—C9	1.365 (6)
N2—N1^i	1.182 (4)	C9—C10	1.402 (5)
N3—N4	1.171 (4)	C9—N10^iii	3.411 (7)
N4—N5	1.142 (5)	C11—C12	1.348 (5)
N6—C1	1.329 (4)	C13—C14	1.392 (6)
N6—C5	1.358 (4)	C14—C15	1.358 (6)
N7—C10	1.325 (4)	C15—C16	1.417 (6)
N7—C6	1.360 (4)	C16—C17	1.403 (5)
N8—C13	1.321 (5)	C16—C24	1.426 (6)
N8—C17	1.355 (4)	C17—C18	1.437 (5)
N9—C22	1.325 (5)	C18—C19	1.412 (5)
N9—C18	1.366 (5)	C19—C20	1.405 (6)
N10—N11	1.133 (6)	C19—C23	1.442 (6)
N10—O1W	2.792 (6)	C20—C21	1.363 (6)
N11—N10^ii	1.133 (6)	C21—C22	1.391 (5)
C1—C2	1.396 (5)	C23—C24	1.335 (6)
C2—C3	1.358 (6)	O1W—O2W	2.857 (5)
N3—Cu1—N6	92.21 (12)	C3—C4—C12	124.5 (3)
N3—Cu1—N9	92.55 (12)	N6—C5—C4	123.5 (3)
N6—Cu1—N9	171.83 (11)	N6—C5—C6	116.6 (3)
N3—Cu1—N7	170.71 (12)	C4—C5—C6	120.0 (3)
N6—Cu1—N7	81.49 (11)	N7—C6—C7	124.0 (3)
N9—Cu1—N7	94.53 (11)	N7—C6—C5	116.6 (3)
N3—Cu1—N8	101.94 (13)	C7—C6—C5	119.4 (3)
N6—Cu1—N8	94.74 (11)	C6—C7—C8	116.7 (3)
N9—Cu1—N8	77.76 (11)	C6—C7—C11	119.4 (3)
N7—Cu1—N8	85.46 (11)	C8—C7—C11	123.8 (3)
N3—Cu1—N1	89.61 (13)	C9—C8—C7	119.2 (3)
N6—Cu1—N1	84.32 (12)	C8—C9—C10	119.9 (4)
N9—Cu1—N1	102.36 (12)	C8—C9—N10^iii	117.3 (3)
N7—Cu1—N1	83.02 (11)	C10—C9—N10^iii	121.4 (3)
N8—Cu1—N1	168.45 (11)	N7—C10—C9	122.6 (4)
N2—N1—Cu1	112.5 (2)	C12—C11—C7	120.6 (3)
N2—N1—O1W	134.6 (3)	C11—C12—C4	121.4 (3)
Cu1—N1—O1W	102.11 (16)	N8—C13—C14	123.1 (4)
N1^i—N2—N1	180.0	C15—C14—C13	119.3 (4)
N4—N3—Cu1	123.4 (3)	C14—C15—C16	119.7 (4)
N5—N4—N3	177.0 (5)	C17—C16—C15	116.9 (4)
C1—N6—C5	118.3 (3)	C17—C16—C24	119.2 (4)
C1—N6—Cu1	128.5 (2)	C15—C16—C24	123.9 (4)
C5—N6—Cu1	113.0 (2)	N8—C17—C16	122.7 (3)
C10—N7—C6	117.5 (3)	N8—C17—C18	117.7 (3)
C10—N7—Cu1	130.7 (2)	C16—C17—C18	119.7 (3)
C6—N7—Cu1	111.3 (2)	N9—C18—C19	121.6 (3)
C13—N8—C17	118.3 (3)	N9—C18—C17	118.8 (3)
C13—N8—Cu1	132.9 (3)	C19—C18—C17	119.6 (3)
C17—N8—Cu1	108.6 (2)	C20—C19—C18	117.6 (4)
C22—N9—C18	118.7 (3)	C20—C19—C23	124.0 (4)
C22—N9—Cu1	124.0 (3)	C18—C19—C23	118.5 (4)
C18—N9—Cu1	117.1 (2)	C21—C20—C19	119.9 (4)
N11—N10—O1W	140.3 (4)	C20—C21—C22	119.3 (4)
N10^ii—N11—N10	180.0	N9—C22—C21	122.9 (4)
N6—C1—C2	121.9 (3)	C24—C23—C19	121.4 (4)
C3—C2—C1	119.7 (4)	C23—C24—C16	121.5 (4)
C2—C3—C4	120.2 (3)	N10—O1W—O2W	92.79 (17)
C5—C4—C3	116.4 (3)	N10—O1W—N1	112.09 (18)
C5—C4—C12	119.1 (3)	O2W—O1W—N1	154.61 (17)

Symmetry codes: (i) −x, −y, −z+1; (ii) −x, −y, −z; (iii) −x+1, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···N10	0.94	2.25	2.792 (6)	116
O1W—H1WB···N1	0.94	2.24	2.908 (5)	128
O2W—H2WB···O1W	0.94	1.92	2.857 (5)	178
C9—H9A···N10^iii	0.94	2.50	3.411 (7)	163

Symmetry code: (iii) −x+1, −y, −z.