catena-Poly[[chloro­dipyridine­manganese(II)]-μ₃-6-oxo-1,6-dihydro­pyridine-2-carboxyl­ato]

The title one-dimensional chain polymer complex, [Mn(C₆H₄NO₃)Cl(C₆H₅N)₂]_n, was isolated from the reaction of MnCl₂ with 6-oxo-1,6-dihydro­pyridine-2-carboxylic acid (HpicOH) in pyridine. The asymmetric unit contains one [Mn(HPicO)Cl(py)₂] moiety (py is pyridine), with the (HpicO)⁻ ligand acting in a tridentate manner via the two carboxyl­ate O atoms and the pyridone O atom. The operation of inversion centres generates eight- and 14-membered rings and, in conjunction with an a-axis translation, leads to an infinite chain extending along [100]. The Mn...Mn separations in this chain are 5.1069 (6) and 7.1869 (6) Å. The Mn^II atom has a distorted octahedral coordination, with trans-axial pyridine ligands and with three O atoms and the Cl atom in the equatorial plane. The conformation of the 14-membered ring is stabilized by pairs of inversion-related N—H...O hydrogen bonds.

S1. Comment

Manganese is a special metal with a number of oxidation states (II–IV) under normal conditions, which results in many properties in naturally occurring processes and in magnetism, such as the photosynthetic water-oxidizing complex (WOC) of green plants and cyanobacteria containing an Mn₄ unit (Law et al., 1998; Yocum et al., 1999), and the single-molecule magnets represented by Mn₁₂ complexes, with slow-relaxation magnetization and quantum tunnelling of magnetization (Sessoli et al., 1993; Thomas et al., 1996). Carboxylate bridges, which are a common feature of these complexes, are interesting ligands, both because of their ability to assume a large range of coordination modes and because of their biological relevance (Christou et al., 1989; Wieghardt, 1989; Rardin et al., 1991; Akhriff et al., 1999). Low-dimensional extended structures (one-dimensional, chain-like) have attracted particular interest due to their specific structural features and unusual nonlinear optical and magnetic properties (Chen et al., 1993; Cox et al., 1998; Monfort et al., 2000; Matouzenko et al., 2003). 2-Pyridone derivatives have been extensively studied since they cause base mispairing and enzymatic reactions related to bifunctional catalysis (Beak et al., 1976), which show excellent pharmacodynamic properties, justifying the view that this is a very promising new class of totally synthetic antibacterial agents (Li et al., 2000). In contrast with organic compounds with 2-pyridone, a few structures are known of coordination complexes with 2-pyridone ligands. Although 2-oxo-1,2-dihydropyridine-6-carboxylic acid (HpicOH) is a simple 2-pyridone derivative, only three dimer complexes have been reported to date, which coordinate to Re²⁺ (Chattopadhyay et al., 2003), Gd³⁺ (Soares-Santos et al., 2003), and Mn³⁺ ions (Bian et al., 2004). Here, we report the title novel one-dimensional chain Mn^II polymer complex, [MnCl(py)₂(HpicO)]_n, (I).

The asymmetric unit of (I) contains one [MnClPy₂(HPicO)] moiety (Fig. 1). Each (HpicO)⁻ ligand acts in a tridentate manner via the two carboxylate O atoms and the pyridone O atom. Operation of the inversion centres at (1/2,0,0) and (0,0,0) generates eight- and 14-membered rings and, in conjunction with an a-axis translation, leads to an infinite chain extending along [100]. The intra-ring Mn···Mn separations in this chain are 5.1069 (6) and 7.1869 (6) Å. The unique Mn^II atom (Fig. 1) has distorted octahedral coordination, with trans-axial pyridine ligands and with three O atoms and the Cl atom in the equatorial plane (see Table 1 for selected geometric details). The conformation of the 14-membered ring is stabilized by pairs of inversion related N—H···O hydrogen bonds (Table 2).

In the crystal structure of (I), surprisingly, there are no significant π–π interactions, but the [100] chains are linked to form sheets in the (001) plane by a series of inversion related C—H···Cl contacts (Table 2) centred about inversion centres at (0,1/2,0), (1/2,1/2,0), (1,1/2,0) etc., as shown in Fig. 2.

The observed temperature dependence of the magnetic susceptibility showed a monotonic increase of χMT from 2 K to 300 K, indicating antiferromagnetic interaction between Mn^II ions. Although the magetic properties of the above-mentioned double-chain compound should be analyzed using the alternating chain model (Fisher, 1964), we could not obtain a quantitative analysis due to inevitable contamination of (I) with impurities.

S2. Experimental

To a solution of MnCl₂·2H₂O (65.0 mg, 0.4 mol) in pyridine (10 ml) was added HpicOH (55.8 mg, 0.4 mmol). The green–brown solution was stirred for 6 or 7 h and hexane was added slowly. Colourless block crystals of (I) suitable for X-ray analysis were obtained after two weeks. Selected IR data (KBr pellet, ν, cm⁻¹): 3337 (b), 3104 (w), 3061 (m), 3039 (w), 3002 (m), 1602 (s), 1490 (m), 1446 (s), 1364 (w), 1221 (m), 1154 (w), 1081 (m), 1038 (m), 1008 (m), 754 (s), 694 (s), 629 (m), 421 (m).

S3. Refinement

All H atoms were clearly revealed in difference maps and were subsequently allowed for in the correct sites as riding atoms in the final refinement cycles, with C—H = 0.95 and N—H = 0.83 Å, and with U_iso(H) = 1.2U_eq(C,N). Please check added text.

Computing details

Data collection: CrystalClear (Rigaku, 2001); cell refinement: CrystalClear; data reduction: TEXSAN (Molecular Structure Corporation & Rigaku, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976) and Mercury (Bruno et al., 2002) Please check; software used to prepare material for publication: TEXSAN.

Figures

Fig. 1. The molecular structure of (I), with the atom-numbering scheme, showing 50% probability displacement ellipsoids together with the N1—H1···O3 hydrogen bonds. For clarity, the pyridine ligands are not shown. [Symmetry codes: (i) 1 − x, −y, −z; (ii) 1 + x, y, z; (iii) −x, −y, −z; (iv) x − 1, y, z.] Fig. 2. The two-dimensional molecular packing in (I), via C—H···Cl contacts between chains. [Symmetry code: (i) −x, −y, −z; (ii) 1 − x, 1 − y, −z.]

catena-Poly[[chlorodipyridinemanganese(II)]-µ₃-6-oxo-1,6-dihydropyridine- 2-carboxylato]

Crystal data

[Mn(C6H4NO3)Cl(C6H5N)2]	F(000) = 788.0
Mr = 386.70	Dx = 1.479 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.7107 Å
Hall symbol: -P 2ybc	Cell parameters from 5361 reflections
a = 9.9034 (10) Å	θ = 3.2–27.5°
b = 10.9374 (9) Å	µ = 0.93 mm^−1
c = 16.408 (2) Å	T = 150 K
β = 102.252 (5)°	Prism, colourless
V = 1736.7 (3) Å^3	0.20 × 0.10 × 0.10 mm
Z = 4

Data collection

Rigaku/MSC Mercury CCD area-detector diffractometer	3530 reflections with I > 2σ(I)
Detector resolution: 14.62 pixels mm^-1	Rint = 0.023
ω scans	θmax = 27.5°
Absorption correction: multi-scan (REQAB; Jacobson, 1998)	h = −12→12
Tmin = 0.823, Tmax = 0.911	k = −13→14
13156 measured reflections	l = −21→19
3925 independent reflections

Refinement

Refinement on F^2	w = 1/[σ^2(Fo^2) + (0.0218P)^2 + 0.9672P] where P = (Fo^2 + 2Fc^2)/3
R[F^2 > 2σ(F^2)] = 0.030	(Δ/σ)max < 0.001
wR(F^2) = 0.062	Δρmax = 0.33 e Å^−3
S = 1.10	Δρmin = −0.23 e Å^−3
3530 reflections	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
217 parameters	Extinction coefficient: 0.0000
H-atom parameters constrained

Special details

Refinement. Refinement using reflections with F² > −10.0 σ(F²). The weighted R-factor (wR) and goodness of fit (S) are based on F². R-factor (gt) are based on F. The threshold expression of F² > 2.0 σ(F²) is used only for calculating R-factor (gt).

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

	x	y	z	Uiso*/Ueq
Mn1	0.69299 (2)	0.15917 (2)	0.023240 (10)	0.01218 (7)
Cl1	0.77101 (4)	0.34465 (3)	0.10361 (2)	0.01978 (9)
O1	0.48792 (10)	0.18038 (9)	0.04645 (7)	0.0173 (2)
O2	0.36522 (10)	0.00894 (9)	0.05040 (6)	0.0157 (2)
O3	−0.10940 (10)	0.12216 (9)	−0.01573 (7)	0.0178 (2)
N1	0.12458 (12)	0.13502 (10)	0.01106 (8)	0.0137 (2)
N2	0.61953 (13)	0.26612 (12)	−0.09599 (8)	0.0167 (3)
N3	0.77430 (13)	0.03583 (12)	0.13481 (8)	0.0183 (3)
C1	−0.00259 (15)	0.18776 (13)	−0.01270 (9)	0.0152 (3)
C2	−0.00461 (16)	0.31430 (14)	−0.03299 (11)	0.0211 (3)
C3	0.11562 (17)	0.37752 (14)	−0.02642 (12)	0.0252 (4)
C4	0.24421 (16)	0.31832 (14)	0.00044 (11)	0.0216 (3)
C5	0.24649 (15)	0.19677 (13)	0.01734 (9)	0.0147 (3)
C6	0.37773 (14)	0.12171 (13)	0.03997 (9)	0.0135 (3)
C7	0.54786 (17)	0.36959 (14)	−0.09311 (10)	0.0202 (3)
C8	0.48926 (18)	0.43673 (15)	−0.16341 (11)	0.0260 (4)
C9	0.50764 (19)	0.39582 (16)	−0.24014 (10)	0.0278 (4)
C10	0.58356 (19)	0.29058 (16)	−0.24416 (10)	0.0265 (4)
C11	0.63741 (17)	0.22879 (14)	−0.17102 (10)	0.0209 (3)
C12	0.70418 (17)	−0.05803 (15)	0.15701 (10)	0.0226 (3)
C13	0.7566 (3)	−0.13315 (18)	0.22421 (13)	0.0380 (5)
C14	0.8872 (3)	−0.1099 (2)	0.27066 (13)	0.0446 (5)
C15	0.9611 (2)	−0.0135 (2)	0.24830 (13)	0.0413 (5)
C16	0.90128 (18)	0.05706 (17)	0.18069 (11)	0.0302 (4)
H1	0.1282	0.0610	0.0224	0.0164*
H2	−0.0905	0.3550	−0.0512	0.0253*
H3	0.1131	0.4620	−0.0400	0.0303*
H4	0.3280	0.3630	0.0066	0.0259*
H7	0.5367	0.3983	−0.0403	0.0242*
H8	0.4379	0.5089	−0.1590	0.0312*
H9	0.4685	0.4395	−0.2896	0.0333*
H10	0.5983	0.2614	−0.2961	0.0318*
H11	0.6895	0.1566	−0.1739	0.0251*
H12	0.6140	−0.0742	0.1252	0.0271*
H13	0.7036	−0.1994	0.2380	0.0455*
H14	0.9255	−0.1596	0.3173	0.0535*
H15	1.0517	0.0041	0.2789	0.0496*
H16	0.9524	0.1239	0.1658	0.0362*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mn1	0.00876 (11)	0.01180 (11)	0.01539 (11)	−0.00045 (8)	0.00124 (8)	0.00075 (8)
Cl1	0.01956 (18)	0.01620 (18)	0.02256 (19)	−0.00576 (14)	0.0022 (1)	−0.0031 (1)
O1	0.0097 (5)	0.0183 (5)	0.0241 (6)	−0.0036 (4)	0.0039 (4)	−0.0035 (5)
O2	0.0134 (5)	0.0137 (6)	0.0190 (6)	−0.0008 (4)	0.0014 (4)	−0.0008 (4)
O3	0.0094 (5)	0.0124 (5)	0.0322 (7)	−0.0006 (4)	0.0059 (5)	0.0014 (5)
N1	0.0113 (6)	0.0087 (6)	0.0216 (7)	−0.0007 (5)	0.0047 (5)	0.0012 (5)
N2	0.0165 (6)	0.0169 (7)	0.0173 (7)	0.0010 (5)	0.0049 (5)	0.0025 (5)
N3	0.0169 (7)	0.0169 (7)	0.0194 (7)	0.0013 (6)	−0.0001 (5)	0.0014 (5)
C1	0.0111 (7)	0.0139 (8)	0.0216 (8)	0.0002 (6)	0.0056 (6)	0.0000 (6)
C2	0.0139 (8)	0.0147 (8)	0.0359 (10)	0.0030 (6)	0.0078 (7)	0.0048 (7)
C3	0.0218 (8)	0.0110 (8)	0.0457 (11)	−0.0001 (7)	0.0135 (8)	0.0036 (7)
C4	0.0142 (7)	0.0153 (8)	0.0371 (10)	−0.0044 (6)	0.0097 (7)	−0.0018 (7)
C5	0.0106 (7)	0.0153 (7)	0.0190 (8)	−0.0020 (6)	0.0048 (6)	−0.0032 (6)
C6	0.0118 (7)	0.0161 (8)	0.0127 (7)	−0.0011 (6)	0.0031 (6)	−0.0030 (6)
C7	0.0224 (8)	0.0201 (8)	0.0199 (8)	0.0037 (7)	0.0085 (7)	0.0012 (6)
C8	0.0277 (9)	0.0214 (9)	0.0292 (9)	0.0084 (7)	0.0069 (8)	0.0072 (7)
C9	0.0318 (10)	0.0292 (10)	0.0213 (9)	0.0018 (8)	0.0032 (7)	0.0102 (7)
C10	0.0363 (10)	0.0274 (9)	0.0175 (8)	−0.0018 (8)	0.0095 (7)	0.0012 (7)
C11	0.0234 (8)	0.0192 (8)	0.0220 (8)	0.0020 (7)	0.0088 (7)	−0.0006 (7)
C12	0.0210 (8)	0.0223 (9)	0.0237 (9)	−0.0009 (7)	0.0033 (7)	0.0012 (7)
C13	0.0402 (11)	0.0305 (11)	0.0405 (12)	−0.0042 (9)	0.0025 (9)	0.0165 (9)
C14	0.0430 (12)	0.0426 (12)	0.0409 (12)	0.0051 (10)	−0.0077 (10)	0.0233 (10)
C15	0.0291 (10)	0.0433 (12)	0.0416 (11)	−0.0020 (9)	−0.0147 (9)	0.0139 (10)
C16	0.0232 (9)	0.0302 (10)	0.0321 (10)	−0.0059 (8)	−0.0055 (8)	0.0073 (8)

Geometric parameters (Å, º)

Mn1—Cl1	2.4534 (4)	C4—C5	1.357 (3)
Mn1—O1	2.1568 (11)	C4—H4	0.950
Mn1—O2^i	2.2085 (10)	C5—C6	1.515 (2)
Mn1—O3^ii	2.2212 (11)	C7—C8	1.387 (3)
Mn1—N2	2.2629 (13)	C7—H7	0.950
Mn1—N3	2.2790 (13)	C8—C9	1.384 (3)
O1—C6	1.2509 (17)	C8—H8	0.950
O2—C6	1.2550 (17)	C9—C10	1.384 (3)
O3—C1	1.2704 (18)	C9—H9	0.950
N1—C1	1.3647 (18)	C10—C11	1.382 (3)
N1—C5	1.3681 (19)	C10—H10	0.950
N1—H1	0.830	C11—H11	0.950
N2—C7	1.342 (3)	C12—C13	1.385 (3)
N2—C11	1.344 (3)	C12—H12	0.950
N3—C12	1.333 (3)	C13—C14	1.378 (3)
N3—C16	1.342 (2)	C13—H13	0.950
C1—C2	1.423 (3)	C14—C15	1.378 (4)
C2—C3	1.361 (3)	C14—H14	0.950
C2—H2	0.950	C15—C16	1.378 (3)
C3—C4	1.413 (3)	C15—H15	0.950
C3—H3	0.950	C16—H16	0.950
Cl1···C15^iii	3.5515 (19)	O3···N2^vii	3.1495 (18)
Cl1···C3^iv	3.5640 (17)	O3···C16^vii	3.280 (3)
O1···C10^v	3.3794 (19)	O3···C11^vii	3.3805 (18)
O1···C9^v	3.564 (2)	O3···O3^vi	3.410 (2)
O2···O3^vi	2.8612 (14)	O3···C1^vi	3.5663 (17)
O2···C9^v	3.5817 (18)	N3···C10^v	3.565 (3)
O3···N1^vi	2.8188 (15)	C6···C9^v	3.569 (3)
O3···N3^vii	3.0866 (18)	C9···C12^viii	3.343 (3)
Cl1—Mn1—O1	90.98 (3)	N1—C5—C4	119.47 (14)
Cl1—Mn1—O2^i	176.73 (4)	N1—C5—C6	116.64 (12)
Cl1—Mn1—O3^ii	96.27 (3)	C4—C5—C6	123.84 (14)
Cl1—Mn1—N2	92.52 (4)	O1—C6—O2	127.03 (13)
Cl1—Mn1—N3	92.32 (4)	O1—C6—C5	115.49 (13)
O1—Mn1—O2^i	92.29 (4)	O2—C6—C5	117.48 (13)
O1—Mn1—O3^ii	172.14 (4)	N2—C7—C8	123.26 (16)
O1—Mn1—N2	87.42 (5)	N2—C7—H7	118.4
O1—Mn1—N3	96.16 (5)	C8—C7—H7	118.4
O2^i—Mn1—O3^ii	80.47 (4)	C7—C8—C9	118.22 (16)
O2^i—Mn1—N2	87.63 (5)	C7—C8—H8	120.9
O2^i—Mn1—N3	87.33 (5)	C9—C8—H8	120.9
O3^ii—Mn1—N2	89.23 (5)	C8—C9—C10	119.33 (15)
O3^ii—Mn1—N3	86.60 (5)	C8—C9—H9	120.3
N2—Mn1—N3	173.93 (5)	C10—C9—H9	120.3
Mn1—O1—C6	140.09 (10)	C9—C10—C11	118.60 (16)
Mn1^i—O2—C6	139.95 (10)	C9—C10—H10	120.7
Mn1^vii—O3—C1	131.53 (10)	C11—C10—H10	120.7
C1—N1—C5	123.99 (12)	N2—C11—C10	123.05 (16)
C1—N1—H1	118.0	N2—C11—H11	118.5
C5—N1—H1	118.0	C10—C11—H11	118.5
Mn1—N2—C7	118.74 (11)	N3—C12—C13	123.06 (15)
Mn1—N2—C11	123.66 (11)	N3—C12—H12	118.5
C7—N2—C11	117.51 (14)	C13—C12—H12	118.5
Mn1—N3—C12	124.04 (10)	C12—C13—C14	118.71 (19)
Mn1—N3—C16	118.53 (12)	C12—C13—H13	120.6
C12—N3—C16	117.43 (14)	C14—C13—H13	120.6
O3—C1—N1	118.86 (13)	C13—C14—C15	118.91 (19)
O3—C1—C2	124.75 (14)	C13—C14—H14	120.5
N1—C1—C2	116.38 (14)	C15—C14—H14	120.5
C1—C2—C3	120.47 (14)	C14—C15—C16	118.74 (18)
C1—C2—H2	119.8	C14—C15—H15	120.6
C3—C2—H2	119.8	C16—C15—H15	120.6
C2—C3—C4	120.48 (15)	N3—C16—C15	123.15 (18)
C2—C3—H3	119.8	N3—C16—H16	118.4
C4—C3—H3	119.8	C15—C16—H16	118.4
C3—C4—C5	119.17 (15)	C3—H3—C2	36.0
C3—C4—H4	120.4	C3—H3—Cl1^iv	148.7
C5—C4—H4	120.4	C2—H3—Cl1^iv	160.9

Symmetry codes: (i) −x+1, −y, −z; (ii) x+1, y, z; (iii) −x+2, y+1/2, −z+1/2; (iv) −x+1, −y+1, −z; (v) x, −y+1/2, z+1/2; (vi) −x, −y, −z; (vii) x−1, y, z; (viii) x, −y+1/2, z−1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O3^vi	0.83	2.01	2.8188 (15)	164
C3—H3···Cl1^iv	0.95	2.72	3.5640 (17)	149

Symmetry codes: (iv) −x+1, −y+1, −z; (vi) −x, −y, −z.