(2,2′-Biquinoline-κ²N,N′)dichloropalladium(II), -copper(II) and -zinc(II)

In the three title complexes, namely (2,2′-biquinoline-κ²N,N′)dichloro­palladium(II), [PdCl₂(C₁₈H₁₂N₂)], (I), and the corresponding copper(II), [CuCl₂(C₁₈H₁₂N₂)], (II), and zinc(II) complexes, [ZnCl₂(C₁₈H₁₂N₂)], (III), each metal atom is four-coordinate and bonded by two N atoms of a 2,2′-biquinoline molecule and two Cl atoms. The Pd^II atom has a distorted cis-square-planar coordination geometry, whereas the Cu^II and Zn^II atoms both have a distorted tetra­hedral geometry. The dihedral angles between the N—M—N and Cl—M—Cl planes are 14.53 (13), 65.42 (15) and 85.19 (9)° for (I), (II) and (III), respectively. The structure of (II) has twofold imposed symmetry.

S1. Comment

Pt^II complexes, such as cis-diamminedichloroplatinum(II) (cisplatin), cis-[(H₃N)₂PtCl₂] (Rosenberg et al., 1969), cis-diammine(1,1-cyclobutanedicarboxylato)platinum(II) (carboplatin), cis-[(H₃N)₂Pt(C₆H₃O₄)] and (trans-R,R-cyclohexane-1,2-diamineoxalato)platinum(II) (oxaliplatin), [(C₆H₁₂N₂)Pt(C₂O₄)] (Wong & Giadomenico, 1999), are well known as therapeutic anticancer drugs (Jakupec et al., 2003). As a consequence of the similar coordination behaviour of Pd^II and Pt^II, Pd^II complexes have been treated as ideal models for studies of square-planar complexes (Rau & van Eldik, 1996) such as [Pd(en)Cl₂] (en is ethylenediamine) and cis-[Pd(NH₃)₂Cl₂], and much interest has been focused on the creation of new antitumour Pd^II complexes, such as [Pd(asme)₂] (asme is an anionic form of the acetone Schiff base of S-methyldithiocarbazate; Ali et al., 2002) or [Pd(bpy)(cbdca)] (bpy is 2,2'-bipyridine and cbdca is 1,1-cyclobutanedicarboxylate; Mansuri-Torshizi et al., 2001).

We have previously synthesized mixed-ligand Pd^II complexes of a cis-square-planar coordination geometry with N and O ligand atoms and have determined their structures, e.g. [Pd(bd)(phen)] (bd is 1,2-benzenediol and phen is 1,10-phenanthroline; Okabe et al., 2003), [Pd(nad)(bpy)] (nad is 2,3-naphthalenediol and bpy is 2,2'-bipyridine), [Pd(nad)(biq)] (biq is 2,2'-biquinoline; Okabe et al., 2004) or [Pd(cbdca)(bpy)] and [Pd(cbdca)(phen)] (Muranishi & Okabe, 2004). The complex of Pd^II with the heterocyclic N,N'-bidentate ligand biq, [Pd(biq)(en)](ClO₄)₂ (en is ethylenediamine), shows antitumour activity (Cusmano & Giannetto, 1997).

It is important to clarify whether the transition metals Cu^II and Zn^II have a cis-square-planar coordination geometry with the same ligands as the Pd^II or Pt^II complexes, since Cu^II and Zn^II are also able to have a square-planar [see, for example, Koman et al. (1998), Fun et al. (2002) and Liu et al. (2002) for Cu^II, and Wu (2004) and Dastidar & Goldberg (1996) for Zn^II] or tetrahedral coordination geometry [see, for example, Malkov et al. (2001), Małecka et al. (1998) and Dessy & Fares (1985) for Cu^II, and Zhu et al. (2002) and Halvorsen et al. (1995) for Zn^II]. Furthermore, both Cu^II and Zn^II have many important biological functions as cofactors in enzymes, or antimicrobial activity as complexes (Okide et al., 2000; Patel et al., 1999).

In this study, the structures of Pd^II, Cu^II and Zn^II complexes with biq and Cl⁻ ligands have been characterized, as [PdCl₂(biq)], (I), [CuCl₂(biq)], (II), and [ZnCl₂(biq)], (III), and these are shown in Figs. 1, 2 and 3, respectively. Selected coordination bond distances and angles are shown in Table 1. A search of the February 2005 release of the Cambridge Structural Database (Allen, 2002) for relevant MN₂Cl₂ complexes (error-free, non-disordered, R < 0.05) gave 94, 100 and 37 hits for M = Pd, Cu and Zn, respectively. Analysis with VISTA (Reference?) gave the following distance ranges and mean values (Å): Pd—N 2.000–2.114, 2.034; Pd—Cl 2.262–2.331, 2.994; Cu—N 1.948–2.106, 2.105; Cu—Cl 2.186–2.498, 2.286; Zn—N 2.009–2.138, 2.056; Zn—Cl 2.171–2.290, 2.217. The dimensions in Table 1 are in entirely in accord with these known dimensions.

The coordination geometry around the central metal Pd^II atom of (I) is remarkably different from those in (II) and (III). In (I), the Pd^II atom has a distorted cis-square-planar coordination geometry, whereas in (II) and (III), the Cu^II and Zn^II atoms have a distorted tetrahedral geometry. The dihedral angles between the N—M—N and Cl—M—Cl planes are 14.53 (13), 65.42 (15) and 85.19 (9)° for (I), (II) and (III), respectively.

In (I), the overall structure is not planar. The Pd^II and two Cl atoms deviate from the mean plane formed through atoms N1/C2/C12/N2 in the same direction, by 0.810 (4) Å for Pd1, 1.739 (8) Å for Cl1 and 2.128 (7) Å for Cl2. As a result of this distortion, the five-membered ring (Pd/N1/C2/C12/N2) forms a half-chair with Pd^II as the flap. This deviation seems to be caused by the intramolecular steric hindrance between biq moieties (C9—H9 and C19—H19) and Cl atoms (Cl1 and Cl2), as reflected by the relatively short Cl1···H9 and Cl2···H19 separations of 2.70 Å and 2.68 Å, respectively. The two quinoline rings of the biq ligand of (I) are bowed in the same direction, like two wings, with a dihedral angle of 17.81 (8) Å.

In (II) and (III), the deviations of the central metal atoms from the mean plane (N1/C2/C12/N2) are zero for Cu^II and 0.267 (7) Å for Zn^II, as the five-membered rings (M/N1/C2/C12/N2) of (II) and (III) form a planar and a slight half-chair form for M = Cu^II and M = Zn^II, respectively. The Cl···H separations are Cl1···H9(1 − x,y,3/2 − z) [= Cl1(1 − x,y,3/2 − z)···H9] 2.77 Å in (II), and Cl1···H19 3.15 Å and Cl2···H9 3.63 Å in (III). The dihedral angles between the quinoline rings in the biq ligand are 1.4 (2) and 10.3 (2) Å for (II) and (III), respectively. These indicate that the conformation of the biq ligand of (II) is almost planar, while that of (III) is slightly bowed.

Figs. 4, 5 and 6 show the crystal packing of complexes (I), (II) and (III), respectively. The crystal structures of the three complexes are stabilized by π–π interactions between inversion-related biq ligands. In (I) and (III), C—H···Cl hydrogen bonds are present (Table 2). In (I), the N1 ring (N1/C2–C10) stacks with the inversion-related N1 ring, with a centroid···centroid separation of 3.770 (3) Å [between the centroids of rings N1/C2–C5/C10 and C5–C10(−x, −y, −z)]. The N2 ring (N2/C12–C20) also stacks with neighbouring N2 rings, with centroid···centroid separations of 3.653 (3) and 3.689 (3) Å [between the centroids of rings N2/C12–C15/C20 and C15–C20(1 − x, 1 − y, −z), and between the centroids of rings N2/C12–C15/C20 and N2/C12–C15/C20(1 − x, −y, −z), respectively]. In (II), the N1 ring (N1/C2–C5/C10) stacks with the inversion-related N1 ring at (1 − x, −y, 1 − z), with a centroid···centroid separation of 3.769 (3) Å. In (III), the N1 ring (N1/C2–C10) stacks with the inversion-related neighbouring N1 ring at (−x, −y, 1 − z), with a centroid···centroid separation of 3.519 (3) Å between the C5–C10 rings. The N2 ring (N2/C12–C20) stacks with the inversion-related neighbouring N2 ring at (1 − x, 1 − y, 1 − z), with a centroid···centroid separation of 3.539 (3) Å between inversion-related N2/C12–C15/C20 rings.

S2. Experimental

Orange plate crystals of (I) were obtained by slow evaporation of a dimethylformamide (DMF) solution of a mixture of biq and PdCl₂ (molar ratio 1:1) at room temperature. Red plate crystals of (II) were obtained by slow evaporation of a DMF solution of a mixture of biq and CuCl₂·2H₂O (molar ratio 1:1) at room temperature. Colourless plate crystals of (III) were obtained by slow evaporation of a DMF solution of a mixture of biq and ZnCl₂ (molar ratio 1:1) at room temperature.

S3. Refinement

All H atoms were located in the difference Fourier maps and were then treated as riding, with C—H = 0.93 Å and with U_iso(H) = 1.2U_eq(C).

Computing details

For all compounds, data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1992); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: TEXSAN (Molecular Structure Corporation & Rigaku, 2000); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: TEXSAN.

Figures

	Fig. 1. A drawing of (I), with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. A drawing of (II), with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii. Atoms labelled with an asterisk are at the symmetry position ?. Please provide symmetry code.
	Fig. 3. A drawing of (III), with the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 4. The packing of (I), showing the π–π interactions between inversion-related ligand molecules and the C—H···Cl-type hydrogen bonds (dashed lines). [Symmetry code: (i) x, 1/2 − y, −1/2 − z.]
	Fig. 5. The packing of (II), showing the π–π interactions between inversion-related ligand molecules.
	Fig. 6. The packing of (III), showing the π–π interactions between inversion-related ligand molecules and the C—H···Cl type hydrogen bonds (dashed lines). [Symmetry code: (i) 1/2 + x, 1/2 − y, 1/2 + z.]

(I) (2,2'-Biquinoline-κ²N,N')chloropalladium(II)

Crystal data

[PdCl2(C18H12N2)]	F(000) = 856
Mr = 433.62	Dx = 1.802 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ybc	Cell parameters from 25 reflections
a = 13.017 (4) Å	θ = 14.5–15.0°
b = 7.726 (4) Å	µ = 1.49 mm^−1
c = 15.972 (3) Å	T = 296 K
β = 95.675 (19)°	Plate, orange
V = 1598.4 (10) Å^3	0.30 × 0.20 × 0.05 mm
Z = 4

Data collection

Rigaku AFC-5R diffractometer	2724 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.043
Graphite monochromator	θmax = 27.5°, θmin = 2.6°
ω/2θ scans	h = 0→16
Absorption correction: ψ scan (North et al., 1968)	k = 0→10
Tmin = 0.606, Tmax = 0.928	l = −20→20
3825 measured reflections	3 standard reflections every 150 reflections
3669 independent reflections	intensity decay: 0.2%

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)] = 0.027	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.076	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.034P)^2 + 0.2227P] where P = (Fo^2 + 2Fc^2)/3
3669 reflections	(Δ/σ)max = 0.001
208 parameters	Δρmax = 0.40 e Å^−3
0 restraints	Δρmin = −0.38 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
Pd1	0.285333 (17)	0.21575 (3)	0.141722 (13)	0.03799 (8)
Cl1	0.14692 (7)	0.21821 (15)	0.21894 (6)	0.0683 (3)
Cl2	0.33172 (7)	0.47385 (12)	0.20474 (5)	0.0555 (2)
N1	0.23319 (18)	0.0243 (3)	0.05765 (14)	0.0385 (5)
N2	0.40119 (19)	0.2113 (3)	0.06532 (15)	0.0377 (5)
C2	0.2670 (2)	0.0633 (4)	−0.01699 (17)	0.0387 (7)
C3	0.2131 (3)	0.0121 (4)	−0.09382 (19)	0.0465 (8)
H3	0.2365	0.0443	−0.1447	0.056*
C4	0.1266 (3)	−0.0852 (5)	−0.0922 (2)	0.0515 (8)
H4	0.0877	−0.1134	−0.1423	0.062*
C5	0.0951 (2)	−0.1436 (4)	−0.0154 (2)	0.0454 (7)
C6	0.0107 (3)	−0.2572 (4)	−0.0102 (3)	0.0575 (10)
H6	−0.0288	−0.2918	−0.0590	0.069*
C7	−0.0129 (3)	−0.3156 (5)	0.0650 (3)	0.0644 (11)
H7	−0.0696	−0.3879	0.0676	0.077*
C8	0.0466 (3)	−0.2690 (5)	0.1391 (3)	0.0630 (10)
H8	0.0313	−0.3155	0.1901	0.076*
C9	0.1270 (3)	−0.1558 (5)	0.1375 (2)	0.0528 (8)
H9	0.1650	−0.1233	0.1874	0.063*
C10	0.1524 (2)	−0.0883 (4)	0.06021 (19)	0.0408 (7)
C12	0.3660 (2)	0.1568 (4)	−0.01144 (17)	0.0388 (6)
C13	0.4245 (3)	0.1758 (4)	−0.0807 (2)	0.0511 (8)
H13	0.3986	0.1359	−0.1335	0.061*
C14	0.5187 (3)	0.2525 (4)	−0.0699 (2)	0.0529 (9)
H14	0.5561	0.2704	−0.1158	0.063*
C15	0.5596 (2)	0.3050 (4)	0.0110 (2)	0.0477 (8)
C16	0.6583 (3)	0.3816 (5)	0.0269 (3)	0.0600 (10)
H16	0.6977	0.4032	−0.0175	0.072*
C17	0.6960 (3)	0.4238 (5)	0.1065 (3)	0.0664 (11)
H17	0.7598	0.4781	0.1162	0.080*
C18	0.6390 (3)	0.3858 (5)	0.1743 (3)	0.0647 (10)
H18	0.6671	0.4102	0.2288	0.078*
C19	0.5430 (3)	0.3138 (5)	0.1618 (2)	0.0533 (9)
H19	0.5064	0.2886	0.2074	0.064*
C20	0.5000 (2)	0.2780 (4)	0.0798 (2)	0.0427 (7)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Pd1	0.03819 (13)	0.05016 (15)	0.02575 (11)	−0.00225 (11)	0.00383 (8)	−0.00049 (10)
Cl1	0.0522 (5)	0.1038 (8)	0.0522 (5)	−0.0185 (5)	0.0220 (4)	−0.0260 (5)
Cl2	0.0711 (5)	0.0562 (5)	0.0410 (4)	−0.0122 (4)	0.0148 (4)	−0.0075 (4)
N1	0.0373 (12)	0.0459 (15)	0.0324 (12)	0.0011 (11)	0.0033 (10)	0.0014 (11)
N2	0.0411 (13)	0.0381 (13)	0.0344 (12)	0.0027 (11)	0.0062 (10)	0.0066 (11)
C2	0.0457 (16)	0.0388 (16)	0.0321 (14)	0.0094 (13)	0.0064 (12)	0.0014 (12)
C3	0.060 (2)	0.0477 (19)	0.0319 (15)	0.0103 (16)	0.0046 (14)	−0.0026 (13)
C4	0.0545 (19)	0.054 (2)	0.0439 (17)	0.0105 (16)	−0.0078 (15)	−0.0125 (15)
C5	0.0414 (16)	0.0377 (16)	0.0561 (19)	0.0096 (14)	−0.0008 (14)	−0.0119 (15)
C6	0.0464 (19)	0.045 (2)	0.078 (3)	0.0021 (15)	−0.0056 (18)	−0.0215 (18)
C7	0.048 (2)	0.049 (2)	0.097 (3)	−0.0074 (17)	0.014 (2)	−0.011 (2)
C8	0.057 (2)	0.061 (2)	0.074 (3)	−0.0040 (19)	0.0183 (19)	0.009 (2)
C9	0.0429 (17)	0.066 (2)	0.0496 (18)	−0.0052 (17)	0.0027 (14)	0.0063 (17)
C10	0.0361 (15)	0.0417 (17)	0.0441 (16)	0.0053 (13)	0.0017 (12)	−0.0004 (13)
C12	0.0466 (16)	0.0367 (15)	0.0339 (14)	0.0078 (13)	0.0083 (12)	0.0038 (12)
C13	0.068 (2)	0.050 (2)	0.0383 (16)	0.0041 (17)	0.0178 (15)	0.0002 (14)
C14	0.063 (2)	0.047 (2)	0.054 (2)	0.0061 (16)	0.0279 (17)	0.0081 (15)
C15	0.0447 (17)	0.0378 (18)	0.063 (2)	0.0108 (14)	0.0184 (15)	0.0133 (15)
C16	0.0494 (19)	0.044 (2)	0.089 (3)	0.0065 (16)	0.0212 (19)	0.0169 (19)
C17	0.0378 (18)	0.057 (2)	0.104 (3)	0.0001 (17)	0.004 (2)	0.015 (2)
C18	0.0477 (19)	0.071 (3)	0.071 (2)	−0.0032 (19)	−0.0119 (18)	0.009 (2)
C19	0.0460 (18)	0.059 (2)	0.0532 (19)	−0.0031 (16)	−0.0023 (15)	0.0141 (16)
C20	0.0415 (16)	0.0380 (15)	0.0487 (17)	0.0058 (14)	0.0058 (13)	0.0104 (14)

Geometric parameters (Å, º)

Pd1—N2	2.032 (2)	C8—C9	1.366 (5)
Pd1—N1	2.067 (3)	C8—H8	0.93
Pd1—Cl1	2.2819 (10)	C9—C10	1.410 (4)
Pd1—Cl2	2.2878 (13)	C9—H9	0.93
N1—C2	1.345 (3)	C12—C13	1.410 (4)
N1—C10	1.368 (4)	C13—C14	1.358 (5)
N2—C12	1.334 (4)	C13—H13	0.93
N2—C20	1.383 (4)	C14—C15	1.406 (5)
C2—C3	1.408 (4)	C14—H14	0.93
C2—C12	1.473 (4)	C15—C16	1.415 (5)
C3—C4	1.357 (5)	C15—C20	1.422 (4)
C3—H3	0.93	C16—C17	1.356 (5)
C4—C5	1.405 (5)	C16—H16	0.93
C4—H4	0.93	C17—C18	1.403 (5)
C5—C6	1.415 (5)	C17—H17	0.93
C5—C10	1.422 (4)	C18—C19	1.364 (5)
C6—C7	1.346 (6)	C18—H18	0.93
C6—H6	0.93	C19—C20	1.401 (5)
C7—C8	1.396 (6)	C19—H19	0.93
C7—H7	0.93
N2—Pd1—N1	79.24 (10)	C8—C9—C10	120.0 (3)
N2—Pd1—Cl1	175.80 (7)	C8—C9—H9	120.0
N1—Pd1—Cl1	97.53 (7)	C10—C9—H9	120.0
N2—Pd1—Cl2	95.71 (8)	N1—C10—C9	120.6 (3)
N1—Pd1—Cl2	164.82 (7)	N1—C10—C5	120.4 (3)
Cl1—Pd1—Cl2	86.74 (3)	C9—C10—C5	118.9 (3)
C2—N1—C10	119.2 (3)	N2—C12—C13	121.7 (3)
C2—N1—Pd1	107.5 (2)	N2—C12—C2	115.4 (2)
C10—N1—Pd1	129.75 (19)	C13—C12—C2	122.7 (3)
C12—N2—C20	120.0 (3)	C14—C13—C12	119.7 (3)
C12—N2—Pd1	110.48 (19)	C14—C13—H13	120.1
C20—N2—Pd1	128.8 (2)	C12—C13—H13	120.1
N1—C2—C3	122.1 (3)	C13—C14—C15	119.9 (3)
N1—C2—C12	114.7 (2)	C13—C14—H14	120.1
C3—C2—C12	123.2 (3)	C15—C14—H14	120.1
C4—C3—C2	118.8 (3)	C14—C15—C16	122.7 (3)
C4—C3—H3	120.6	C14—C15—C20	118.7 (3)
C2—C3—H3	120.6	C16—C15—C20	118.5 (3)
C3—C4—C5	120.6 (3)	C17—C16—C15	120.5 (3)
C3—C4—H4	119.7	C17—C16—H16	119.8
C5—C4—H4	119.7	C15—C16—H16	119.8
C4—C5—C6	123.1 (3)	C16—C17—C18	120.2 (3)
C4—C5—C10	118.1 (3)	C16—C17—H17	119.9
C6—C5—C10	118.8 (3)	C18—C17—H17	119.9
C7—C6—C5	120.5 (4)	C19—C18—C17	121.2 (4)
C7—C6—H6	119.7	C19—C18—H18	119.4
C5—C6—H6	119.7	C17—C18—H18	119.4
C6—C7—C8	120.9 (4)	C18—C19—C20	119.6 (3)
C6—C7—H7	119.6	C18—C19—H19	120.2
C8—C7—H7	119.6	C20—C19—H19	120.2
C9—C8—C7	120.7 (4)	N2—C20—C19	120.6 (3)
C9—C8—H8	119.6	N2—C20—C15	119.7 (3)
C7—C8—H8	119.6	C19—C20—C15	119.7 (3)

(II) (2,2'-Biquinoline-κ²N,N')chlorocopper(II)

Crystal data

[CuCl2(C18H12N2)]	F(000) = 788
Mr = 390.75	Dx = 1.629 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -C 2yc	Cell parameters from 24 reflections
a = 19.430 (3) Å	θ = 11.0–14.5°
b = 8.528 (2) Å	µ = 1.71 mm^−1
c = 11.884 (3) Å	T = 296 K
β = 125.991 (10)°	Plate, red
V = 1593.2 (6) Å^3	0.30 × 0.10 × 0.10 mm
Z = 4

Data collection

Rigaku AFC-5R diffractometer	1032 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.062
Graphite monochromator	θmax = 27.5°, θmin = 2.6°
ω/2θ scans	h = 0→25
Absorption correction: ψ scan (North et al., 1968)	k = 0→11
Tmin = 0.715, Tmax = 0.843	l = −15→12
1877 measured reflections	3 standard reflections every 150 reflections
1825 independent reflections	intensity decay: 0.0%

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)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.131	H-atom parameters constrained
S = 0.99	w = 1/[σ^2(Fo^2) + (0.0586P)^2] where P = (Fo^2 + 2Fc^2)/3
1825 reflections	(Δ/σ)max < 0.001
105 parameters	Δρmax = 0.70 e Å^−3
0 restraints	Δρmin = −0.71 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	0.5000	0.24318 (8)	0.7500	0.0363 (2)
Cl1	0.39305 (8)	0.40667 (14)	0.61503 (14)	0.0539 (4)
N1	0.55076 (19)	0.0667 (4)	0.7110 (3)	0.0294 (7)
C2	0.5286 (2)	−0.0743 (5)	0.7269 (4)	0.0278 (8)
C3	0.5560 (3)	−0.2142 (5)	0.7026 (5)	0.0381 (10)
H3	0.5392	−0.3110	0.7147	0.046*
C4	0.6079 (3)	−0.2048 (5)	0.6609 (5)	0.0403 (10)
H4	0.6274	−0.2962	0.6457	0.048*
C5	0.6321 (3)	−0.0592 (5)	0.6406 (4)	0.0336 (9)
C6	0.6845 (3)	−0.0422 (6)	0.5947 (5)	0.0429 (11)
H6	0.7059	−0.1307	0.5793	0.051*
C7	0.7036 (3)	0.1025 (6)	0.5732 (5)	0.0481 (12)
H7	0.7382	0.1123	0.5434	0.058*
C8	0.6720 (3)	0.2370 (6)	0.5951 (5)	0.0431 (10)
H8	0.6851	0.3350	0.5781	0.052*
C9	0.6220 (3)	0.2271 (5)	0.6412 (5)	0.0380 (10)
H9	0.6018	0.3176	0.6563	0.046*
C10	0.6015 (2)	0.0782 (5)	0.6654 (4)	0.0317 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cu1	0.0430 (4)	0.0179 (3)	0.0545 (5)	0.000	0.0322 (4)	0.000
Cl1	0.0620 (8)	0.0345 (6)	0.0612 (8)	0.0182 (6)	0.0340 (7)	0.0074 (6)
N1	0.0294 (16)	0.0233 (16)	0.0341 (18)	−0.0005 (14)	0.0179 (15)	0.0000 (14)
C2	0.0297 (19)	0.0251 (19)	0.029 (2)	0.0019 (16)	0.0173 (18)	0.0010 (16)
C3	0.049 (3)	0.023 (2)	0.047 (3)	0.0023 (18)	0.031 (2)	0.0007 (18)
C4	0.045 (2)	0.031 (2)	0.046 (3)	0.0062 (19)	0.028 (2)	−0.003 (2)
C5	0.030 (2)	0.038 (2)	0.030 (2)	0.0038 (18)	0.0159 (19)	0.0003 (19)
C6	0.047 (3)	0.044 (3)	0.045 (3)	0.006 (2)	0.031 (2)	−0.002 (2)
C7	0.038 (2)	0.064 (3)	0.052 (3)	0.000 (2)	0.031 (2)	0.002 (3)
C8	0.043 (2)	0.040 (2)	0.051 (3)	0.000 (2)	0.030 (2)	0.007 (2)
C9	0.039 (2)	0.031 (2)	0.051 (3)	−0.0004 (18)	0.030 (2)	0.002 (2)
C10	0.030 (2)	0.032 (2)	0.031 (2)	0.0002 (17)	0.0165 (19)	0.0015 (17)

Geometric parameters (Å, º)

Cu1—N1^i	1.997 (3)	C4—H4	0.93
Cu1—N1	1.997 (3)	C5—C6	1.416 (6)
Cu1—Cl1^i	2.2175 (13)	C5—C10	1.422 (6)
Cu1—Cl1	2.2175 (13)	C6—C7	1.356 (7)
N1—C2	1.328 (5)	C6—H6	0.93
N1—C10	1.379 (5)	C7—C8	1.395 (7)
C2—C3	1.404 (5)	C7—H7	0.93
C2—C2^i	1.500 (7)	C8—C9	1.370 (6)
C3—C4	1.361 (6)	C8—H8	0.93
C3—H3	0.93	C9—C10	1.410 (6)
C4—C5	1.398 (6)	C9—H9	0.93
N1^i—Cu1—N1	82.24 (18)	C4—C5—C6	123.3 (4)
N1^i—Cu1—Cl1^i	133.34 (10)	C4—C5—C10	118.2 (4)
N1—Cu1—Cl1^i	105.13 (10)	C6—C5—C10	118.5 (4)
N1^i—Cu1—Cl1	105.13 (10)	C7—C6—C5	120.3 (4)
N1—Cu1—Cl1	133.34 (10)	C7—C6—H6	119.8
Cl1^i—Cu1—Cl1	102.09 (8)	C5—C6—H6	119.8
C2—N1—C10	119.2 (3)	C6—C7—C8	120.9 (4)
C2—N1—Cu1	113.8 (2)	C6—C7—H7	119.6
C10—N1—Cu1	127.0 (3)	C8—C7—H7	119.6
N1—C2—C3	123.1 (3)	C9—C8—C7	121.2 (4)
N1—C2—C2^i	115.1 (2)	C9—C8—H8	119.4
C3—C2—C2^i	121.9 (2)	C7—C8—H8	119.4
C4—C3—C2	118.5 (4)	C8—C9—C10	119.3 (4)
C4—C3—H3	120.8	C8—C9—H9	120.4
C2—C3—H3	120.8	C10—C9—H9	120.4
C3—C4—C5	120.8 (4)	N1—C10—C9	119.8 (4)
C3—C4—H4	119.6	N1—C10—C5	120.3 (4)
C5—C4—H4	119.6	C9—C10—C5	119.8 (4)

Symmetry code: (i) −x+1, y, −z+3/2.

(III) (2,2'-Biquinoline-κ²N,N')chlorozinc(II)

Crystal data

[ZnCl2(C18H12N2)]	F(000) = 792
Mr = 392.59	Dx = 1.620 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2yn	Cell parameters from 24 reflections
a = 7.986 (2) Å	θ = 11.6–14.7°
b = 12.257 (6) Å	µ = 1.86 mm^−1
c = 16.8390 (16) Å	T = 296 K
β = 102.464 (13)°	Plate, colourless
V = 1609.4 (9) Å^3	0.50 × 0.20 × 0.05 mm
Z = 4

Data collection

Rigaku AFC-5R diffractometer	1835 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.044
Graphite monochromator	θmax = 27.5°, θmin = 2.6°
ω/2θ scans	h = 0→10
Absorption correction: ψ scan (North et al., 1968)	k = 0→15
Tmin = 0.547, Tmax = 0.911	l = −21→21
3943 measured reflections	3 standard reflections every 150 reflections
3686 independent reflections	intensity decay: 1.2%

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)] = 0.044	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.122	H-atom parameters constrained
S = 0.96	w = 1/[σ^2(Fo^2) + (0.0437P)^2] where P = (Fo^2 + 2Fc^2)/3
3686 reflections	(Δ/σ)max < 0.001
208 parameters	Δρmax = 0.41 e Å^−3
0 restraints	Δρmin = −0.40 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
Zn1	0.33341 (7)	0.22824 (5)	0.35773 (3)	0.04252 (17)
Cl1	0.44286 (18)	0.15916 (11)	0.25920 (7)	0.0610 (4)
Cl2	0.07082 (17)	0.29680 (12)	0.32675 (8)	0.0643 (4)
N1	0.3555 (4)	0.1379 (3)	0.46332 (19)	0.0358 (8)
N2	0.5064 (4)	0.3240 (3)	0.43591 (19)	0.0354 (8)
C2	0.4368 (5)	0.1918 (4)	0.5283 (2)	0.0370 (10)
C3	0.4389 (6)	0.1534 (4)	0.6076 (3)	0.0455 (12)
H3	0.4964	0.1923	0.6527	0.068*
C4	0.3570 (6)	0.0597 (4)	0.6175 (3)	0.0486 (12)
H4	0.3565	0.0352	0.6697	0.073*
C5	0.2725 (6)	−0.0012 (4)	0.5500 (3)	0.0407 (11)
C6	0.1841 (6)	−0.1007 (4)	0.5545 (3)	0.0540 (13)
H6	0.1824	−0.1305	0.6051	0.081*
C7	0.1024 (6)	−0.1530 (4)	0.4865 (4)	0.0559 (14)
H7	0.0430	−0.2172	0.4909	0.084*
C8	0.1065 (6)	−0.1108 (4)	0.4086 (3)	0.0567 (14)
H8	0.0517	−0.1482	0.3622	0.085*
C9	0.1900 (6)	−0.0159 (4)	0.4014 (3)	0.0449 (11)
H9	0.1927	0.0112	0.3501	0.067*
C10	0.2730 (6)	0.0418 (4)	0.4715 (3)	0.0400 (11)
C12	0.5308 (5)	0.2910 (4)	0.5129 (2)	0.0367 (10)
C13	0.6445 (6)	0.3460 (4)	0.5761 (3)	0.0444 (11)
H13	0.6588	0.3224	0.6297	0.067*
C14	0.7328 (6)	0.4338 (4)	0.5577 (3)	0.0481 (12)
H14	0.8079	0.4703	0.5991	0.072*
C15	0.7123 (6)	0.4708 (4)	0.4762 (3)	0.0418 (11)
C16	0.7996 (6)	0.5607 (4)	0.4537 (3)	0.0560 (14)
H16	0.8768	0.5991	0.4930	0.084*
C17	0.7719 (7)	0.5923 (5)	0.3741 (4)	0.0657 (16)
H17	0.8310	0.6516	0.3594	0.099*
C18	0.6540 (8)	0.5351 (4)	0.3144 (3)	0.0630 (16)
H18	0.6359	0.5574	0.2605	0.095*
C19	0.5656 (7)	0.4473 (4)	0.3342 (3)	0.0532 (13)
H19	0.4871	0.4109	0.2941	0.080*
C20	0.5941 (6)	0.4122 (4)	0.4160 (3)	0.0399 (11)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.0501 (3)	0.0482 (3)	0.0265 (2)	−0.0026 (3)	0.0022 (2)	0.0004 (3)
Cl1	0.0777 (9)	0.0727 (9)	0.0315 (6)	0.0129 (8)	0.0091 (6)	−0.0043 (6)
Cl2	0.0536 (8)	0.0792 (10)	0.0540 (8)	0.0115 (7)	−0.0020 (6)	0.0057 (7)
N1	0.037 (2)	0.042 (2)	0.0274 (17)	0.0070 (17)	0.0049 (15)	0.0021 (15)
N2	0.038 (2)	0.039 (2)	0.0285 (17)	−0.0006 (17)	0.0038 (15)	−0.0002 (16)
C2	0.036 (2)	0.041 (3)	0.032 (2)	0.0102 (19)	0.0034 (18)	−0.0003 (18)
C3	0.053 (3)	0.052 (3)	0.028 (2)	0.009 (2)	0.003 (2)	0.004 (2)
C4	0.060 (3)	0.050 (3)	0.039 (3)	0.005 (3)	0.016 (2)	0.010 (2)
C5	0.042 (3)	0.037 (3)	0.045 (3)	0.011 (2)	0.015 (2)	0.008 (2)
C6	0.050 (3)	0.053 (3)	0.065 (3)	0.008 (3)	0.024 (3)	0.015 (3)
C7	0.048 (3)	0.044 (3)	0.082 (4)	−0.002 (2)	0.027 (3)	0.002 (3)
C8	0.046 (3)	0.056 (3)	0.068 (4)	−0.004 (3)	0.013 (3)	−0.014 (3)
C9	0.040 (3)	0.049 (3)	0.046 (3)	−0.004 (2)	0.009 (2)	−0.006 (2)
C10	0.036 (3)	0.043 (3)	0.043 (3)	0.009 (2)	0.011 (2)	0.000 (2)
C12	0.036 (2)	0.044 (3)	0.029 (2)	0.007 (2)	0.0040 (17)	−0.0027 (19)
C13	0.042 (3)	0.046 (3)	0.040 (2)	0.010 (2)	−0.002 (2)	0.001 (2)
C14	0.038 (3)	0.052 (3)	0.049 (3)	0.007 (2)	−0.003 (2)	−0.007 (2)
C15	0.029 (2)	0.042 (3)	0.053 (3)	0.001 (2)	0.008 (2)	−0.006 (2)
C16	0.044 (3)	0.056 (3)	0.069 (4)	−0.005 (3)	0.016 (3)	−0.011 (3)
C17	0.069 (4)	0.054 (4)	0.087 (4)	−0.002 (3)	0.045 (4)	−0.004 (3)
C18	0.089 (4)	0.051 (3)	0.058 (3)	−0.006 (3)	0.035 (3)	0.004 (3)
C19	0.064 (3)	0.057 (3)	0.039 (3)	−0.003 (3)	0.015 (2)	0.003 (2)
C20	0.039 (3)	0.042 (3)	0.040 (2)	0.003 (2)	0.011 (2)	−0.004 (2)

Geometric parameters (Å, º)

Zn1—N2	2.058 (3)	C8—C9	1.360 (7)
Zn1—N1	2.070 (3)	C8—H8	0.93
Zn1—Cl1	2.2044 (14)	C9—C10	1.413 (6)
Zn1—Cl2	2.2143 (15)	C9—H9	0.93
N1—C2	1.322 (5)	C12—C13	1.412 (6)
N1—C10	1.371 (6)	C13—C14	1.359 (6)
N2—C12	1.332 (5)	C13—H13	0.93
N2—C20	1.368 (6)	C14—C15	1.420 (7)
C2—C3	1.413 (6)	C14—H14	0.93
C2—C12	1.481 (6)	C15—C16	1.400 (7)
C3—C4	1.349 (6)	C15—C20	1.422 (6)
C3—H3	0.93	C16—C17	1.366 (7)
C4—C5	1.405 (7)	C16—H16	0.93
C4—H4	0.93	C17—C18	1.407 (8)
C5—C6	1.420 (7)	C17—H17	0.93
C5—C10	1.423 (6)	C18—C19	1.367 (7)
C6—C7	1.350 (7)	C18—H18	0.93
C6—H6	0.93	C19—C20	1.413 (6)
C7—C8	1.417 (7)	C19—H19	0.93
C7—H7	0.93
N2—Zn1—N1	80.49 (14)	C8—C9—C10	120.3 (5)
N2—Zn1—Cl1	112.34 (11)	C8—C9—H9	119.9
N1—Zn1—Cl1	117.83 (11)	C10—C9—H9	119.9
N2—Zn1—Cl2	113.89 (11)	N1—C10—C9	119.6 (4)
N1—Zn1—Cl2	107.84 (10)	N1—C10—C5	120.6 (4)
Cl1—Zn1—Cl2	118.53 (5)	C9—C10—C5	119.7 (4)
C2—N1—C10	120.4 (4)	N2—C12—C13	121.6 (4)
C2—N1—Zn1	112.3 (3)	N2—C12—C2	116.5 (4)
C10—N1—Zn1	126.3 (3)	C13—C12—C2	121.9 (4)
C12—N2—C20	120.2 (4)	C14—C13—C12	119.1 (4)
C12—N2—Zn1	112.7 (3)	C14—C13—H13	120.4
C20—N2—Zn1	127.0 (3)	C12—C13—H13	120.4
N1—C2—C3	121.3 (4)	C13—C14—C15	121.0 (4)
N1—C2—C12	116.3 (4)	C13—C14—H14	119.5
C3—C2—C12	122.4 (4)	C15—C14—H14	119.5
C4—C3—C2	119.6 (4)	C16—C15—C14	123.6 (5)
C4—C3—H3	120.2	C16—C15—C20	119.8 (5)
C2—C3—H3	120.2	C14—C15—C20	116.7 (4)
C3—C4—C5	120.9 (4)	C17—C16—C15	120.3 (5)
C3—C4—H4	119.6	C17—C16—H16	119.8
C5—C4—H4	119.6	C15—C16—H16	119.8
C4—C5—C6	124.8 (5)	C16—C17—C18	120.1 (5)
C4—C5—C10	117.2 (4)	C16—C17—H17	120.0
C6—C5—C10	118.0 (5)	C18—C17—H17	120.0
C7—C6—C5	121.2 (5)	C19—C18—C17	121.3 (5)
C7—C6—H6	119.4	C19—C18—H18	119.4
C5—C6—H6	119.4	C17—C18—H18	119.4
C6—C7—C8	120.5 (5)	C18—C19—C20	119.6 (5)
C6—C7—H7	119.7	C18—C19—H19	120.2
C8—C7—H7	119.7	C20—C19—H19	120.2
C9—C8—C7	120.3 (5)	N2—C20—C19	119.8 (4)
C9—C8—H8	119.9	N2—C20—C15	121.3 (4)
C7—C8—H8	119.8	C19—C20—C15	118.9 (4)