The first pyridyl N,N′-coordinated di-2-pyridyl ketone oxime, fac-tricarbonylchloro(di-2-pyridyl ketone oxime)rhenium(I) dimethyl sulfoxide solvate

The structure of the first metal compound of pyridyl N,N′-coordinated di-2-pyridyl ketone oxime (dpk-o), fac-tri­carbonyl­chloro­(di-2-pyridyl-κN ketone oxime)­rhenium(I) di­methyl sulfoxide solvate, [ReCl(C₁₁H₉N₂O)(CO)₃]·C₂H₆OS, (I), is reported. The coordinated atoms (two N atoms from the pyridyl rings, three C atoms from the carbonyl groups and one Cl atom) are in a distorted octahedral arrangement, with the major distortion being due to the constraints associated with the binding of dpk-o. The packing of the mol­ecules shows antiparallel tapes of (I), with a network of classical (O...H—O) and non-classical (O...H—C) hydrogen bonds between the di­methyl sulfoxide solvate molecule and the complexed metal moiety.

S1. Comment

Oximes and their metal complexes have attracted considerable research interest due to their rich physico-chemical properties, reactivity patterns and applications in many important chemical processes (Adams, 2000; Kuznetsov et al., 2000). Although a variety of metal complexes of oximes have been reported, complexes of dipyridyl and dipyridyl-like oximes are scarce (Adams, 2000; Bakir, 1999). Eight structures have been reported for the coordination of di-2-pyridyl ketone oxime (dpk.oxime) (Goher & Mautner, 1999; Jensen et al., 1997; Psomas et al., 1998; Schlemper et al., 1990; Stemmler et al., 1995; Sommerer et al., 1995, 1997). In these reports, dpk.oxime coordinated to the metal centre in a monodentate mode using an N atom of one pyridyl ring, as in [Ag(dpk.oxime)]NO₂ (Sommerer et al., 1995), in a bidentate mode using an N atom of one pyridyl ring and the N atom of the oxime moiety, as in [Co(dpkO,OH)(dpk.oxime)]NO₂·H₂O [dpkO,OH is hydroxy-di-(2-pyridyl)methoxide; Jensen et al., 1997], and in a tridentate mode using combined monodentate and bidentate binding, as in the case of the Cu^I-dimer [CuCl(dpk.oxime)·H₂O]₂ (Goher & Mautner, 1999). No evidence for N,N-dipyridyl coordination of dpk.oxime has been noted to date.

The synthesis and optical and electrochemical behaviour of rhenium-tricarbonyl compounds of pyridyl N,N-coordinated di-2-pyridyl ketone (dpk) and its oxime (dpk.oxime) and hydrazone (dpknph), where dpknph is di-2-pyridyl ketone-p-nitrophenyl hydrazone, have previously been reported by us (Bakir, 1997; Bakir & McKenzie, 1997a,b; Bakir, 1999; Bakir & Abdur-Rashid, 1999; Bakir et al., 2000). These compounds exhibit rich electro- and optical properties and their electrochemical and optical sensing properties have been reported. In the case of dpk.oxime, electrochemical mechanisms for the oxidation and reduction of free and rhenium-coordinated dpk.oxime have been reported (Bakir, 1999). In this report, the structure of the dimethyl sulfoxide solvated title complex, (I), is described and compared with the structures of the rhenium compounds of α-diimine ligands and hydroxy-di-(2-pyridyl)methoxide (dpkO,OH). \sch

The molecular structure of (I) is shown in Fig. 1, and selected bond distances and angles are given in Table 1. Two N atoms from the pyridyl rings, three C atoms from the carbonyl groups and one Cl atom occupy the coordinated site. The three carbonyl groups are in facial positions and are orthogonal, with an average C—Re—C angle of 88.47 (3)°. The Re—C bond distances of the carbonyl groups (Table 1), with an average value of 1.91 (7) Å, are normal and are similar to those reported for a variety of rhenium-carbonyl compounds of the type fac-Re(CO)₃(L—L)X, where L—L is an α-diimine ligand (Xue et al., 1998; Horn & Snow, 1980). For example, in fac-Re(CO)₃(bipy)(OPOF₂), the average Re—C distance is 1.91 (2) Å and the average C—Re—C angle is 87.2 (8)° (Horn & Snow, 1980). The distortion from octahedral geometry in (I) is due to the constraints associated with the binding of the dpk.oxime moiety, as apparent from its N—N bite angle of 80.27 (19)°. The coordinated dpk.oxime forms a six-membered Re1/N1/C15/C4/C25/N2 metallocyclic ring, with the pyridine rings in a butterfly formation. This arrangement leaves one pyridine ring in the equatorial plane, the other in the axial plane and the oxime moiety exposed for potential intermolecular interaction. The N—N bite angle of the coordinated dpk.oxime moiety in (I) is smaller than the value of 84.6 (4)° reported for ReOCl₂(dpkO,OH) (Gerber et al., 1995, 1993) and larger than the value of 74.3 (2)° in fac-Re(CO)₃(bipy)(OPOF2) (Horn & Snow, 1980). These results show that the five-membered Re/N1/C15/C25/N2 rings of α-diimine ligands are more constrained than the six-membered Re1/N1/C15/C4/C25/N2 ring of dpk.oxime.

The packing of the molecules shows stacks of anti-parallel tapes of (I), with a network of hydrogen bonds between the dimethyl sulfoxide solvate and adjacent fac-Re(CO)₃(dpk.oxime)Cl molecules (Fig. 2 and Table 2). The bond distances and angles of the hydrogen bonds are of the same order as those observed in a variety of compounds containing such bonds (Gerber et al., 1995, 1997?; Glusker et al., 1994; Batchelor, et al., 2000).

Owing to their rich physico-chemical properties and reactivity patterns, work is in progress to prepare a variety of metal compounds of dpk.oxime, to explore their solid state structures and electro-optical properties.

S2. Experimental

fac-Re(CO)₃(dpk.oxime)Cl was synthesized as described earlier by Bakir (1999). The dimethyl sulfoxide used for the crystallization was reagent grade and thoroughly deoxygenated prior to use. When fac-Re(CO)₃(dpk.oxime)Cl was allowed to stand in dimethyl sulfoxide for several days at room temperature, yellow crystals of (I) were obtained.

S3. Refinement

H atoms were assigned by assuming idealized geometry, with C—H = 0.96 and 0.93 Å for the aliphatic and aromatic H atoms, respectively, and O—H = 0.82 Å. In the final refinement, seven peaks with residual electron density greater than 1 e Å^-3 were seen. Six are ghosts of the Re atom and one is due to the non-bonding pair of electrons on atom N3 of the oxime moiety. The deepest hole, with an electron density of -1.767 e Å^-3, was observed 0.91 Å from Re.

Computing details

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS; data reduction: SHELXTL (Bruker, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The molecular structure of (I) with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. A view showing the chain of molecules linked by O—H···O and C—H···O hydrogen bonds extending in the b direction. Atom O5^i is at equivalent position x, 1 + y, z. For clarity, all H atoms except those involved in hydrogen bonding have been omitted.

fac-tricarbonylchloro(di-2-pyridyl ketone oxime)rhenium(I) dimethyl sulfoxide solvate

Crystal data

[ReCl(C11H9N3O)(CO)3]·C2H6OS	Z = 2
Mr = 583.02	F(000) = 560
Triclinic, P1	Dx = 1.986 Mg m^−3
a = 9.257 (6) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.483 (2) Å	Cell parameters from 21 reflections
c = 10.6838 (17) Å	θ = 4.9–22.0°
α = 103.807 (12)°	µ = 6.51 mm^−1
β = 92.84 (3)°	T = 298 K
γ = 103.09 (5)°	Irregular, yellow
V = 974.7 (7) Å^3	0.22 × 0.21 × 0.20 mm

Data collection

Bruker P4 diffractometer	3207 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.026
Graphite monochromator	θmax = 25.0°, θmin = 2.0°
2θ/ω scans	h = −10→1
Absorption correction: empirical (using intensity measurements) via ψ scan (North et al., 1968)	k = −11→12
Tmin = 0.213, Tmax = 0.272	l = −12→12
4089 measured reflections	3 standard reflections every 97 reflections
3399 independent reflections	intensity decay: none

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)] = 0.033	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.096	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.08P)^2] where P = (Fo^2 + 2Fc^2)/3
3399 reflections	(Δ/σ)max = 0.002
244 parameters	Δρmax = 1.57 e Å^−3
0 restraints	Δρmin = −1.77 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
Re1	0.63015 (2)	0.742833 (18)	0.738902 (17)	0.03219 (12)
Cl1	0.6008 (2)	0.97255 (17)	0.83720 (18)	0.0510 (4)
C1	0.6381 (8)	0.7808 (7)	0.5712 (7)	0.0496 (16)
C2	0.4177 (7)	0.6718 (7)	0.7033 (6)	0.0432 (14)
C3	0.6479 (7)	0.5668 (6)	0.6589 (6)	0.0410 (13)
N1	0.6380 (6)	0.7077 (5)	0.9346 (5)	0.0358 (10)
N2	0.8713 (5)	0.8274 (5)	0.8031 (5)	0.0355 (10)
O1	0.6457 (8)	0.8021 (7)	0.4711 (5)	0.0732 (16)
O2	0.2899 (5)	0.6249 (6)	0.6846 (6)	0.0686 (15)
O3	0.6528 (7)	0.4591 (5)	0.6053 (6)	0.0673 (15)
N3	0.9199 (9)	0.5250 (6)	0.8431 (7)	0.076 (2)
O4	0.8419 (7)	0.4130 (7)	0.8718 (6)	0.0758 (16)
H4	0.8667	0.3466	0.8298	0.098*
C11	0.5345 (7)	0.7358 (7)	1.0150 (6)	0.0463 (14)
H11	0.4662	0.7808	0.9912	0.043*
C12	0.5268 (9)	0.6997 (8)	1.1318 (7)	0.0565 (17)
H12	0.4556	0.7212	1.1861	0.078*
C13	0.6268 (9)	0.6318 (8)	1.1652 (7)	0.0610 (19)
H13	0.6219	0.6043	1.2418	0.103*
C14	0.7361 (8)	0.6038 (6)	1.0844 (6)	0.0495 (15)
H14	0.8052	0.5588	1.1066	0.076*
C15	0.7388 (6)	0.6446 (5)	0.9712 (6)	0.0372 (12)
C4	0.8623 (7)	0.6319 (6)	0.8878 (6)	0.0390 (12)
C21	0.9462 (7)	0.9455 (6)	0.7831 (7)	0.0459 (14)
H21	0.8926	0.9955	0.7470	0.065*
C22	1.0989 (8)	0.9966 (7)	0.8137 (7)	0.0543 (17)
H22	1.1466	1.0787	0.7984	0.064*
C23	1.1788 (7)	0.9222 (8)	0.8676 (7)	0.0559 (17)
H23	1.2817	0.9523	0.8880	0.054*
C24	1.1014 (7)	0.8019 (7)	0.8902 (6)	0.0459 (14)
H24	1.1526	0.7502	0.9264	0.059*
C25	0.9485 (6)	0.7581 (5)	0.8592 (5)	0.0358 (11)
O5	0.9578 (7)	0.2301 (6)	0.7159 (6)	0.0716 (15)
S1	0.9306 (3)	0.1820 (2)	0.5714 (2)	0.0665 (5)
C5	0.9896 (11)	0.3308 (11)	0.5133 (11)	0.085 (3)
H5A	1.0965	0.3601	0.5256	0.127*
H5B	0.9482	0.4015	0.5605	0.127*
H5C	0.9556	0.3101	0.4227	0.127*
C6	0.7327 (11)	0.1536 (10)	0.5350 (12)	0.088 (3)
H6A	0.6827	0.0729	0.5579	0.132*
H6B	0.7094	0.1431	0.4440	0.132*
H6C	0.7001	0.2295	0.5837	0.132*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Re1	0.03168 (16)	0.03600 (17)	0.02672 (16)	0.00929 (10)	0.00011 (10)	0.00361 (10)
Cl1	0.0540 (9)	0.0466 (8)	0.0527 (9)	0.0220 (7)	0.0067 (7)	0.0043 (7)
C1	0.053 (4)	0.040 (3)	0.052 (4)	0.010 (3)	0.001 (3)	0.007 (3)
C2	0.033 (3)	0.057 (4)	0.038 (3)	0.015 (3)	0.000 (2)	0.007 (3)
C3	0.040 (3)	0.044 (3)	0.034 (3)	0.010 (3)	−0.001 (2)	0.001 (3)
N1	0.037 (3)	0.037 (2)	0.030 (2)	0.005 (2)	0.000 (2)	0.0076 (19)
N2	0.030 (2)	0.035 (2)	0.040 (3)	0.0075 (19)	0.005 (2)	0.007 (2)
O1	0.098 (4)	0.089 (4)	0.034 (3)	0.016 (3)	0.003 (3)	0.025 (3)
O2	0.036 (3)	0.090 (4)	0.071 (4)	0.003 (3)	−0.003 (2)	0.018 (3)
O3	0.082 (4)	0.053 (3)	0.060 (3)	0.026 (3)	−0.007 (3)	−0.004 (3)
N3	0.106 (5)	0.036 (3)	0.072 (4)	0.001 (3)	−0.051 (4)	0.018 (3)
O4	0.073 (4)	0.079 (4)	0.079 (4)	0.023 (3)	0.010 (3)	0.024 (3)
C11	0.044 (3)	0.050 (3)	0.039 (3)	0.008 (3)	0.009 (3)	0.001 (3)
C12	0.058 (4)	0.061 (4)	0.044 (4)	0.004 (3)	0.019 (3)	0.008 (3)
C13	0.079 (5)	0.057 (4)	0.041 (4)	0.001 (4)	0.005 (4)	0.018 (3)
C14	0.059 (4)	0.045 (3)	0.039 (3)	0.000 (3)	−0.003 (3)	0.014 (3)
C15	0.034 (3)	0.032 (3)	0.039 (3)	0.002 (2)	−0.005 (2)	0.003 (2)
C4	0.044 (3)	0.038 (3)	0.038 (3)	0.018 (2)	0.000 (2)	0.007 (2)
C21	0.043 (3)	0.035 (3)	0.057 (4)	0.006 (3)	0.003 (3)	0.010 (3)
C22	0.044 (4)	0.045 (3)	0.061 (4)	−0.006 (3)	0.001 (3)	0.007 (3)
C23	0.033 (3)	0.066 (4)	0.058 (4)	0.003 (3)	−0.004 (3)	0.007 (3)
C24	0.039 (3)	0.055 (4)	0.043 (3)	0.018 (3)	−0.005 (3)	0.007 (3)
C25	0.036 (3)	0.036 (3)	0.035 (3)	0.013 (2)	0.001 (2)	0.005 (2)
O5	0.098 (4)	0.059 (3)	0.066 (3)	0.036 (3)	0.004 (3)	0.018 (3)
S1	0.0816 (13)	0.0509 (10)	0.0718 (13)	0.0333 (10)	0.0053 (10)	0.0094 (9)
C5	0.076 (6)	0.089 (6)	0.103 (8)	0.021 (5)	0.025 (5)	0.047 (6)
C6	0.085 (7)	0.060 (5)	0.112 (9)	0.007 (5)	−0.010 (6)	0.023 (5)

Geometric parameters (Å, º)

Re1—C3	1.888 (6)	C14—C15	1.375 (8)
Re1—C2	1.922 (6)	C14—H14	0.9300
Re1—C1	1.927 (8)	C15—C4	1.493 (8)
Re1—N1	2.208 (5)	C4—C25	1.490 (8)
Re1—N2	2.214 (5)	C21—C22	1.386 (9)
Re1—Cl1	2.4685 (17)	C21—H21	0.9300
C1—O1	1.145 (9)	C22—C23	1.385 (11)
C2—O2	1.161 (8)	C22—H22	0.9300
C3—O3	1.149 (8)	C23—C24	1.384 (10)
N1—C15	1.352 (8)	C23—H23	0.9300
N1—C11	1.354 (8)	C24—C25	1.383 (8)
N2—C25	1.340 (7)	C24—H24	0.9300
N2—C21	1.346 (8)	O5—S1	1.494 (6)
N3—O4	1.343 (9)	S1—C6	1.795 (10)
N3—C4	1.345 (9)	S1—C5	1.796 (9)
O4—H4	0.8200	C6—H6A	0.9600
C11—C12	1.388 (10)	C6—H6B	0.9600
C11—H11	0.9300	C6—H6C	0.9600
C12—C13	1.370 (12)	C5—H5A	0.9600
C12—H12	0.9300	C5—H5B	0.9600
C13—C14	1.399 (11)	C5—H5C	0.9600
C13—H13	0.9300
C3—Re1—C2	87.1 (3)	C13—C14—H14	120.8
C3—Re1—C1	87.9 (3)	N1—C15—C14	122.3 (6)
C2—Re1—C1	90.4 (3)	N1—C15—C4	116.3 (5)
C3—Re1—N1	93.0 (2)	C14—C15—C4	121.1 (5)
C2—Re1—N1	93.7 (2)	N3—C4—C25	112.7 (6)
C1—Re1—N1	175.9 (2)	N3—C4—C15	129.9 (6)
C3—Re1—N2	95.2 (2)	C25—C4—C15	117.1 (5)
C2—Re1—N2	173.6 (2)	N2—C21—C22	123.4 (6)
C1—Re1—N2	95.6 (3)	N2—C21—H21	118.3
N1—Re1—N2	80.27 (19)	C22—C21—H21	118.3
C3—Re1—Cl1	178.04 (19)	C23—C22—C21	118.3 (6)
C2—Re1—Cl1	91.5 (2)	C23—C22—H22	120.8
C1—Re1—Cl1	90.7 (2)	C21—C22—H22	120.8
N1—Re1—Cl1	88.52 (14)	C24—C23—C22	118.3 (6)
N2—Re1—Cl1	86.22 (14)	C24—C23—H23	120.9
O1—C1—Re1	178.4 (7)	C22—C23—H23	120.9
O2—C2—Re1	177.1 (6)	C25—C24—C23	120.3 (6)
O3—C3—Re1	176.4 (6)	C25—C24—H24	119.9
C15—N1—C11	118.4 (5)	C23—C24—H24	119.9
C15—N1—Re1	119.8 (4)	N2—C25—C24	121.7 (5)
C11—N1—Re1	121.4 (4)	N2—C25—C4	117.2 (5)
C25—N2—C21	118.0 (5)	C24—C25—C4	121.2 (5)
C25—N2—Re1	120.1 (4)	O5—S1—C6	104.8 (5)
C21—N2—Re1	121.9 (4)	O5—S1—C5	105.5 (5)
O4—N3—C4	111.6 (7)	C6—S1—C5	98.6 (5)
N3—O4—H4	109.5	S1—C6—H6A	109.5
N1—C11—C12	122.3 (7)	S1—C6—H6B	109.5
N1—C11—H11	118.9	H6A—C6—H6B	109.5
C12—C11—H11	118.9	S1—C6—H6C	109.5
C13—C12—C11	118.4 (7)	H6A—C6—H6C	109.5
C13—C12—H12	120.8	H6B—C6—H6C	109.5
C11—C12—H12	120.8	S1—C5—H5A	109.5
C12—C13—C14	120.1 (6)	S1—C5—H5B	109.5
C12—C13—H13	120.0	H5A—C5—H5B	109.5
C14—C13—H13	120.0	S1—C5—H5C	109.5
C15—C14—C13	118.3 (7)	H5A—C5—H5C	109.5
C15—C14—H14	120.8	H5B—C5—H5C	109.5

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O4—H4···O5	0.82	1.88	2.681 (9)	164
C6—H6C···O3	0.96	2.51	3.369 (12)	150
C21—H21···O5^i	0.93	2.50	3.211 (9)	133

Symmetry code: (i) x, y+1, z.