Di­aqua(2,2'-bi­pyridine)­malonato­manganese(II)

In the crystal structure of the title compound, [Mn(C₃H₂O₄)(C₁₀H₈N₂)(H₂O)₂], the Mn^II atom demonstrates a distorted octahedral geometry, being coordinated by two N atoms of a 2,2'-bi­pyridine ligand, two O atoms from the carboxyl­ate groups of the chelating malonate dianion and two O atoms of two cis water mol­ecules. The complex mol­ecules are linked to form a three-dimensional supramolecular array by both hydrogen-bonding interactions between coordinated water and the carboxyl­ate groups of neighboring mol­ecules and aromatic [pi]-[pi]-stacking interactions of the bi­pyridine rings.

S1. Comment

In recent years, considerable research effort has been put into the one-, two- and three-dimensional manganese(II) complexes with dicarboxylate ligands which have some potential applications in molecular-based magnets, catalysis, and supramolecular chemistry (Li et al., 2002; Devereux et al., 2000; Shi et al., 2000). The malonate dianion may act as a bidentate or tridentate bridging ligands to form various structural topologies (Filippova et al., 2000; Li et al., 1997; Lightfoot & Snedden, 1999). To the best of our knowledge, there are five reports on the structures of manganese(II) complexes with malonate (mal), viz. [Mn(mal)(H₂O)₂] (Lis & Matuszewski, 1979), [Mn(mal)(phen)₂] (phen is 1,10-phenanthroline; Wang et al., 2000), [Mn₃(mal)₄(H₂O)₆] (Wei et al., 1996), [CaMn(mal)₂(H₂O)₄] (de Muro et al., 2000) and [MnCu(mal)₂(H₂O)₄] (Ruiz-Perez et al., 2000). Both [Mn(mal)(H₂O)₂] and [Mn(mal)(phen)₂] were mononuclear structures in which the malonate ligands act as chelating ligands, and the others were found to be polymeric in which the malonate ligands serve as a syn–anti bridge. We report here the preparation and crystal structure of the title Mn^II complex, diaqua(2,2'-bipyridine)malonatomanganese(II), (I), with a chelating malonate ligand.

The molecular structure of (I) is shown in Fig. 1. The title complex exists as discrete monomers. A malonate dianion chelates the Mn^II atom through two O atoms from different carboxylate groups. The Mn^II atom are also coordinated by two 2,2'-bipyridine N atoms and two O atoms of two cis water molecules. The Mn site exhibits a distorted octahedral coordination sphere with the bond angles ranging from 161.39 (7) to 176.94 (7)° for trans angles and from 72.22 (7) to 104.64 (7)° for others. The Mn—O(carboxylate) bond distances are 2.1215 (17) and 2.1667 (16) Å, which are comparable with those reported for [Mn(mal)(phen)₂] (Wang et al., 2000). The Mn—O(water) distances of 2.1595 (19) and 2.1757 (19) Å are comparable with those found in [Mn₂(mal)₄(H₂O)₆] (Wei et al., 1996). The Mn—N bond lengths are in good agreement with the corresponding bond lengths found in a previously reported complex (McCann et al., 1998). The six-membered malonate chelate ring has a boat configuration and the stability of this ring is the reason that malonate coordinates only to one metal atom and does not act as a bridge between metal atoms.

Both hydrogen-bonding and π–π-stacking interactions play an important role in constructing the three-dimensional supramolecular structure. As shown in Fig. 2, complex molecules are linked to each other through hydrogen bonds between coordinated water molecules and the carboxylate groups of neighboring molecules to form layers in the crystal. Neighboring layers are linked to each other through π–π-stacking interactions between the 2,2'-bipyridine rings of adjacent molecules with face-to-face separations of ca 3.62 and 3.95 Å.

S2. Experimental

An ethanol solution (10 ml) of 2,2'-bipyridine (0.156 g, 1 mmol) was added slowly to an aqueous solution (10 ml) of MnCl₂·4H₂O (0.198 g, 1 mmol) with continuous stirring and refluxing. A large amount of precipitate was produced. An aqueous solution (10 ml) of malonic acid (0.116 g, 1 mmol), neutralized with an aqueous solution of NaOH (0.080 g, 2 mmol), was added slowly to the above reaction mixture with continuous stirring and refluxing until the precipitate had dissolved. After half an hour, the reaction mixture was cooled to room temperature and filtered. Yellow single crystals were obtained from the filtrate after a week. Crystals of the title complex suitable for X-ray analysis were obtained by slow evaporation from an ethanol solution.

S3. Refinement

All the water H atoms were located in a difference Fourier map and the the remaining H atoms were fixed geometrically and allowed to ride on their parent atoms.

Computing details

Data collection: XSCANS User's Manual (Siemens, 1991); cell refinement: XSCANS; data reduction: SHELXTL-Plus (Sheldrick, 1990a); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990b); 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), showing ellipsoids at the 35% probability level.
	Fig. 2. The molecular packing diagram. Hydrogen bonds are illustrated as dotted line.

(I)

Crystal data

[Mn(C3H2O4)(C10H8N2)(H2O)2]	F(000) = 716
Mr = 349.20	Dx = 1.547 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.834 (2) Å	Cell parameters from 26 reflections
b = 9.408 (2) Å	θ = 3.7–14.8°
c = 20.532 (4) Å	µ = 0.91 mm^−1
β = 97.75 (2)°	T = 296 K
V = 1499.4 (6) Å^3	Prism, yellow
Z = 4	0.50 × 0.42 × 0.38 mm

Data collection

Siemens P4 diffractometer	2210 reflections with I > 2σ(I)
Radiation source: normal-focus sealed tube	Rint = 0.010
Graphite monochromator	θmax = 25.0°, θmin = 2.0°
ω scans	h = 0→9
Absorption correction: empirical (using intensity measurements) (North et al., 1968)	k = 0→11
Tmin = 0.843, Tmax = 0.996	l = −24→24
3153 measured reflections	3 standard reflections every 97 reflections
2647 independent reflections	intensity decay: 2.6%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.031	H atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.080	w = 1/[σ^2(Fo^2) + (0.0396P)^2 + 0.4939P] where P = (Fo^2 + 2Fc^2)/3
S = 1.06	(Δ/σ)max < 0.001
2647 reflections	Δρmax = 0.57 e Å^−3
216 parameters	Δρmin = −0.38 e Å^−3
4 restraints	Extinction correction: SHELXL97, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0055 (8)

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
Mn	0.18242 (4)	0.41635 (4)	0.328984 (15)	0.03395 (14)
O1	0.1359 (2)	0.53713 (19)	0.23848 (7)	0.0452 (4)
O2	0.1992 (3)	0.6244 (2)	0.14481 (8)	0.0577 (5)
O3	0.4472 (2)	0.43297 (19)	0.31814 (8)	0.0505 (4)
O4	0.6497 (2)	0.5458 (3)	0.27577 (11)	0.0861 (8)
O5	−0.0881 (2)	0.3901 (2)	0.33636 (10)	0.0518 (5)
O6	0.1673 (2)	0.1952 (2)	0.29776 (10)	0.0509 (5)
N1	0.1735 (3)	0.6162 (2)	0.39192 (9)	0.0419 (5)
N2	0.2592 (2)	0.3530 (2)	0.43586 (9)	0.0408 (5)
C1	0.1257 (4)	0.7445 (3)	0.36856 (13)	0.0572 (7)
H1	0.1061	0.7571	0.3232	0.069*
C2	0.1042 (4)	0.8591 (3)	0.40821 (16)	0.0696 (9)
H2	0.0697	0.9469	0.3902	0.084*
C3	0.1349 (4)	0.8405 (3)	0.47485 (15)	0.0704 (9)
H3	0.1219	0.9160	0.5030	0.085*
C4	0.1846 (4)	0.7102 (3)	0.49965 (13)	0.0593 (7)
H4	0.2055	0.6963	0.5449	0.071*
C5	0.2040 (3)	0.5984 (2)	0.45720 (11)	0.0394 (5)
C6	0.2613 (3)	0.4555 (3)	0.48113 (10)	0.0388 (5)
C7	0.3198 (4)	0.4287 (3)	0.54682 (12)	0.0578 (7)
H7	0.3232	0.5013	0.5777	0.069*
C8	0.3725 (4)	0.2948 (3)	0.56571 (13)	0.0702 (9)
H8	0.4118	0.2755	0.6096	0.084*
C9	0.3670 (4)	0.1897 (3)	0.51982 (15)	0.0717 (9)
H9	0.4006	0.0975	0.5319	0.086*
C10	0.3108 (4)	0.2230 (3)	0.45527 (13)	0.0590 (7)
H10	0.3087	0.1516	0.4238	0.071*
C11	0.2343 (3)	0.5513 (2)	0.19476 (11)	0.0391 (5)
C12	0.4020 (4)	0.4679 (4)	0.20319 (13)	0.0615 (8)
H12A	0.3760	0.3680	0.1956	0.074*
H12B	0.4714	0.4989	0.1701	0.074*
C13	0.5063 (3)	0.4845 (3)	0.27045 (12)	0.0493 (6)
H5A	−0.124 (3)	0.3108 (15)	0.3425 (13)	0.053 (9)*
H5B	−0.167 (3)	0.439 (3)	0.3190 (13)	0.062 (9)*
H6A	0.231 (3)	0.156 (3)	0.2750 (13)	0.071 (10)*
H6B	0.073 (2)	0.156 (3)	0.2896 (15)	0.083 (11)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mn	0.0348 (2)	0.0395 (2)	0.02761 (19)	−0.00011 (15)	0.00448 (13)	−0.00203 (15)
O1	0.0401 (9)	0.0640 (11)	0.0321 (8)	0.0119 (8)	0.0071 (7)	0.0093 (8)
O2	0.0779 (13)	0.0587 (11)	0.0378 (10)	0.0101 (10)	0.0124 (9)	0.0138 (8)
O3	0.0337 (8)	0.0704 (12)	0.0465 (10)	−0.0058 (8)	0.0027 (7)	0.0120 (9)
O4	0.0374 (11)	0.1198 (19)	0.0992 (17)	−0.0124 (12)	0.0022 (10)	0.0655 (15)
O5	0.0355 (10)	0.0494 (12)	0.0714 (13)	0.0032 (9)	0.0109 (9)	0.0057 (10)
O6	0.0392 (10)	0.0502 (11)	0.0656 (12)	−0.0043 (9)	0.0153 (9)	−0.0233 (9)
N1	0.0512 (12)	0.0383 (11)	0.0351 (10)	0.0015 (9)	0.0015 (9)	−0.0021 (8)
N2	0.0480 (11)	0.0391 (11)	0.0345 (10)	0.0000 (9)	0.0030 (8)	0.0006 (9)
C1	0.0738 (19)	0.0442 (15)	0.0488 (15)	0.0077 (14)	−0.0088 (13)	0.0011 (12)
C2	0.084 (2)	0.0421 (15)	0.078 (2)	0.0154 (15)	−0.0073 (17)	−0.0045 (15)
C3	0.090 (2)	0.0525 (18)	0.068 (2)	0.0141 (16)	0.0091 (17)	−0.0224 (15)
C4	0.079 (2)	0.0584 (18)	0.0418 (14)	0.0069 (15)	0.0118 (13)	−0.0115 (13)
C5	0.0419 (12)	0.0435 (13)	0.0332 (12)	−0.0008 (10)	0.0072 (10)	−0.0056 (10)
C6	0.0406 (12)	0.0462 (14)	0.0304 (11)	−0.0059 (10)	0.0081 (9)	−0.0009 (10)
C7	0.0784 (19)	0.0616 (18)	0.0323 (13)	−0.0012 (15)	0.0033 (12)	−0.0002 (12)
C8	0.095 (2)	0.074 (2)	0.0389 (15)	−0.0011 (18)	−0.0034 (15)	0.0157 (15)
C9	0.094 (2)	0.0554 (18)	0.0608 (18)	0.0082 (17)	−0.0074 (16)	0.0188 (15)
C10	0.0780 (19)	0.0466 (16)	0.0492 (15)	0.0066 (14)	−0.0030 (14)	0.0005 (12)
C11	0.0452 (13)	0.0416 (13)	0.0300 (11)	−0.0010 (10)	0.0029 (10)	−0.0045 (10)
C12	0.0579 (17)	0.086 (2)	0.0446 (14)	0.0178 (15)	0.0210 (13)	0.0049 (14)
C13	0.0332 (13)	0.0615 (16)	0.0537 (15)	0.0086 (12)	0.0072 (11)	0.0185 (13)

Geometric parameters (Å, º)

Mn—O3	2.1215 (17)	C2—C3	1.368 (4)
Mn—O5	2.1595 (19)	C2—H2	0.9300
Mn—O1	2.1667 (16)	C3—C4	1.364 (4)
Mn—O6	2.1757 (19)	C3—H3	0.9300
Mn—N2	2.2751 (19)	C4—C5	1.387 (3)
Mn—N1	2.2877 (19)	C4—H4	0.9300
O1—C11	1.267 (3)	C5—C6	1.480 (3)
O2—C11	1.235 (3)	C6—C7	1.388 (3)
O3—C13	1.237 (3)	C7—C8	1.365 (4)
O4—C13	1.255 (3)	C7—H7	0.9300
O5—H5A	0.814 (10)	C8—C9	1.363 (4)
O5—H5B	0.816 (10)	C8—H8	0.9300
O6—H6A	0.816 (10)	C9—C10	1.375 (4)
O6—H6B	0.820 (10)	C9—H9	0.9300
N1—C1	1.334 (3)	C10—H10	0.9300
N1—C5	1.340 (3)	C11—C12	1.520 (3)
N2—C10	1.333 (3)	C12—C13	1.515 (4)
N2—C6	1.338 (3)	C12—H12A	0.9700
C1—C2	1.375 (4)	C12—H12B	0.9700
C1—H1	0.9300
O3—Mn—O5	176.94 (7)	C4—C3—H3	120.3
O3—Mn—O1	85.70 (6)	C2—C3—H3	120.3
O5—Mn—O1	93.85 (7)	C3—C4—C5	119.8 (3)
O3—Mn—O6	93.13 (7)	C3—C4—H4	120.1
O5—Mn—O6	84.04 (7)	C5—C4—H4	120.1
O1—Mn—O6	104.64 (7)	N1—C5—C4	120.9 (2)
O3—Mn—N2	89.17 (7)	N1—C5—C6	116.79 (19)
O5—Mn—N2	92.09 (8)	C4—C5—C6	122.3 (2)
O1—Mn—N2	163.06 (7)	N2—C6—C7	121.0 (2)
O6—Mn—N2	91.74 (7)	N2—C6—C5	116.70 (19)
O3—Mn—N1	95.95 (7)	C7—C6—C5	122.2 (2)
O5—Mn—N1	87.10 (7)	C8—C7—C6	119.4 (3)
O1—Mn—N1	92.24 (7)	C8—C7—H7	120.3
O6—Mn—N1	161.39 (7)	C6—C7—H7	120.3
N2—Mn—N1	72.22 (7)	C9—C8—C7	119.5 (3)
C11—O1—Mn	127.96 (15)	C9—C8—H8	120.2
C13—O3—Mn	125.98 (16)	C7—C8—H8	120.2
Mn—O5—H5A	119 (2)	C8—C9—C10	118.5 (3)
Mn—O5—H5B	127 (2)	C8—C9—H9	120.7
H5A—O5—H5B	109 (3)	C10—C9—H9	120.7
Mn—O6—H6A	126 (2)	N2—C10—C9	122.8 (3)
Mn—O6—H6B	120 (2)	N2—C10—H10	118.6
H6A—O6—H6B	107 (3)	C9—C10—H10	118.6
C1—N1—C5	118.4 (2)	O2—C11—O1	123.9 (2)
C1—N1—Mn	124.69 (16)	O2—C11—C12	118.3 (2)
C5—N1—Mn	116.59 (15)	O1—C11—C12	117.7 (2)
C10—N2—C6	118.6 (2)	C13—C12—C11	113.7 (2)
C10—N2—Mn	123.99 (16)	C13—C12—H12A	108.8
C6—N2—Mn	117.26 (15)	C11—C12—H12A	108.8
N1—C1—C2	123.2 (2)	C13—C12—H12B	108.8
N1—C1—H1	118.4	C11—C12—H12B	108.8
C2—C1—H1	118.4	H12A—C12—H12B	107.7
C3—C2—C1	118.2 (3)	O3—C13—O4	122.5 (2)
C3—C2—H2	120.9	O3—C13—C12	117.9 (2)
C1—C2—H2	120.9	O4—C13—C12	119.5 (2)
C4—C3—C2	119.4 (3)
O3—Mn—O1—C11	21.2 (2)	N1—C1—C2—C3	0.6 (5)
O5—Mn—O1—C11	−155.8 (2)	C1—C2—C3—C4	−0.2 (5)
O6—Mn—O1—C11	−70.9 (2)	C2—C3—C4—C5	0.2 (5)
N2—Mn—O1—C11	93.9 (3)	C1—N1—C5—C4	0.7 (4)
N1—Mn—O1—C11	117.0 (2)	Mn—N1—C5—C4	−173.5 (2)
O5—Mn—O3—C13	75.8 (14)	C1—N1—C5—C6	−178.4 (2)
O1—Mn—O3—C13	−5.9 (2)	Mn—N1—C5—C6	7.4 (3)
O6—Mn—O3—C13	98.6 (2)	C3—C4—C5—N1	−0.4 (4)
N2—Mn—O3—C13	−169.7 (2)	C3—C4—C5—C6	178.6 (3)
N1—Mn—O3—C13	−97.7 (2)	C10—N2—C6—C7	1.6 (4)
O3—Mn—N1—C1	94.7 (2)	Mn—N2—C6—C7	−174.75 (19)
O5—Mn—N1—C1	−84.9 (2)	C10—N2—C6—C5	179.6 (2)
O1—Mn—N1—C1	8.8 (2)	Mn—N2—C6—C5	3.3 (3)
O6—Mn—N1—C1	−146.5 (2)	N1—C5—C6—N2	−7.2 (3)
N2—Mn—N1—C1	−178.1 (2)	C4—C5—C6—N2	173.7 (2)
O3—Mn—N1—C5	−91.46 (17)	N1—C5—C6—C7	170.8 (2)
O5—Mn—N1—C5	88.89 (17)	C4—C5—C6—C7	−8.3 (4)
O1—Mn—N1—C5	−177.36 (17)	N2—C6—C7—C8	−1.5 (4)
O6—Mn—N1—C5	27.3 (3)	C5—C6—C7—C8	−179.4 (3)
N2—Mn—N1—C5	−4.24 (16)	C6—C7—C8—C9	0.1 (5)
O3—Mn—N2—C10	−79.3 (2)	C7—C8—C9—C10	1.1 (5)
O5—Mn—N2—C10	98.0 (2)	C6—N2—C10—C9	−0.3 (4)
O1—Mn—N2—C10	−151.5 (2)	Mn—N2—C10—C9	175.7 (2)
O6—Mn—N2—C10	13.9 (2)	C8—C9—C10—N2	−1.0 (5)
N1—Mn—N2—C10	−175.8 (2)	Mn—O1—C11—O2	−178.73 (17)
O3—Mn—N2—C6	96.83 (17)	Mn—O1—C11—C12	4.0 (3)
O5—Mn—N2—C6	−85.96 (17)	O2—C11—C12—C13	132.2 (3)
O1—Mn—N2—C6	24.6 (3)	O1—C11—C12—C13	−50.4 (3)
O6—Mn—N2—C6	−170.06 (16)	Mn—O3—C13—O4	149.2 (2)
N1—Mn—N2—C6	0.32 (16)	Mn—O3—C13—C12	−32.8 (3)
C5—N1—C1—C2	−0.8 (4)	C11—C12—C13—O3	67.8 (3)
Mn—N1—C1—C2	172.9 (2)	C11—C12—C13—O4	−114.1 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5A···O2^i	0.81 (2)	1.88 (2)	2.692 (3)	178 (2)
O5—H5B···O4^ii	0.81 (3)	1.88 (3)	2.688 (3)	177 (3)
O6—H6A···O2^iii	0.82 (3)	1.82 (3)	2.626 (3)	171 (3)
O6—H6B···O4^i	0.82 (2)	2.00 (2)	2.816 (3)	179 (3)

Symmetry codes: (i) −x, y−1/2, −z+1/2; (ii) x−1, y, z; (iii) −x+1, y−1/2, −z+1/2.