Di­aqua­di­acetyl­acetonatozinc(II)

The title compound, [Zn(C₅H₇O₂)₂(H₂O)₂], crystallizes with the Zn atom on a centre of inversion and one acetyl­acetonato and one water mol­ecule in the asymmetric unit. It is isostructural with the Co, Mg, Ni, Mn and Fe complexes.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.020
• wR factor = 0.056
• Data-to-parameter ratio = 18.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent ...          ?
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Zn1    -   O3     =       6.47 su

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

---

S1. Comment

We report here the X-ray crystal structure analysis of diaquadiacetylacetonatozinc(II), (I). We have recently synthesized the purple coordination polymer (1) (see Scheme) from CuBr₂ and 2,5-bis(pyrazol-1-yl)-1,4-dihydroxybenzene (Dinnebier et al., 2002) and have now become interested in the physical and chemical properties of the dinuclear transition metal complex (2) (see Scheme). We have therefore prepared (I), the synthesis of which has been achieved according to a literature procedure (Rudolph & Henry, 1967) as indicated in the reaction Scheme.

In (I), the Zn atom is located on a centre of inversion and the asymmetric unit contains one acetylacetonate anion and one water molecule. The acetylacetonate is almost planar (r.m.s.d. = 0.043 Å for all seven non-H atoms). The Zn atom is displaced from this plane by 0.466 (1) Å. The bond from Zn to the water molecule is significantly longer than the bonds to the acetylacetone O atoms (see Table 1). The crystal packing is stabilized by hydrogen bonds (see Table 2) from the water molecule to the two acetylacetonate O atoms.

The title compound is isostructural with the Co (Bullen, 1959; Laugier & Mathieu, 1975), Mg (Morosin, 1967), Ni (Montgomery & Lingafelter, 1964), Mn (Montgomery & Lingafelter, 1968; Onuma & Shibata, 1970), Fe (Laugier & Mathieu, 1975; Tsodikov et al., 1995) complexes.

S2. Experimental

The title compound was synthesized by stirring a slurry of ZnSO₄, 2,4-pentadione, NaOH and water at ambient temperature. After 1 h, (I) precipitated quantitatively and was filtered off. After washing, the title compound was recrystalized from ethyl acetate (yield 64%).

S3. Refinement

H atoms bonded to C atoms were refined with fixed individual displacement parameters [U_iso(H) = 1.2U_eq(C) or 1.5 U_eq(C_methyl)] using a riding model with C—H = 0.95 Å or methyl C—H = 0.98 Å, respectively. The methyl groups were allowed to rotate but not to tip. The H atoms bonded to O were refined isotropically.

Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 1991); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures

Fig. 1. Perspective view of the title compound with the atom numbering; displacement ellipsoids are at the 50% probability level.

(I)

Crystal data

[Zn(C5H7O2)2(H2O)2]	F(000) = 312
Mr = 299.61	Dx = 1.601 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 15112 reflections
a = 10.7987 (9) Å	θ = 3.7–28.5°
b = 5.3744 (4) Å	µ = 1.99 mm^−1
c = 11.1259 (11) Å	T = 100 K
β = 105.781 (7)°	Block, colourless
V = 621.37 (9) Å^3	0.34 × 0.25 × 0.23 mm
Z = 2

Data collection

Stoe IPDS-II two-circle diffractometer	1601 independent reflections
Radiation source: fine-focus sealed tube	1476 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.058
ω scans	θmax = 28.7°, θmin = 3.8°
Absorption correction: multi-scan (MULABS; Spek, 1990; Blessing, 1995)	h = −14→13
Tmin = 0.495, Tmax = 0.631	k = −7→7
10528 measured reflections	l = −15→15

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)] = 0.020	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.056	H atoms treated by a mixture of independent and constrained refinement
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0336P)^2 + 0.0697P] where P = (Fo^2 + 2Fc^2)/3
1601 reflections	(Δ/σ)max < 0.001
89 parameters	Δρmax = 0.31 e Å^−3
0 restraints	Δρmin = −0.54 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	0.0000	0.5000	0.5000	0.01306 (8)
O1	0.14665 (8)	0.72607 (15)	0.59558 (7)	0.01549 (16)
O2	0.11843 (8)	0.33940 (15)	0.40837 (7)	0.01551 (16)
O3	0.05805 (9)	0.21091 (16)	0.64230 (8)	0.01956 (17)
H3A	0.074 (2)	0.072 (4)	0.629 (2)	0.035 (5)*
H3B	0.0589 (18)	0.223 (4)	0.7128 (18)	0.034 (5)*
C1	0.35960 (11)	0.8401 (2)	0.70108 (10)	0.0170 (2)
H1A	0.3559	1.0094	0.6676	0.025*
H1B	0.4466	0.7732	0.7136	0.025*
H1C	0.3380	0.8433	0.7811	0.025*
C2	0.26444 (10)	0.67686 (19)	0.60989 (9)	0.01366 (19)
C3	0.31338 (12)	0.48701 (19)	0.54791 (11)	0.0156 (2)
H3	0.4039	0.4619	0.5723	0.019*
C4	0.23981 (11)	0.33165 (19)	0.45313 (9)	0.01429 (19)
C5	0.30887 (12)	0.1372 (2)	0.39740 (10)	0.0184 (2)
H5A	0.2761	−0.0283	0.4097	0.028*
H5B	0.4014	0.1448	0.4386	0.028*
H5C	0.2939	0.1689	0.3078	0.028*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Zn1	0.01310 (11)	0.01347 (11)	0.01253 (11)	−0.00015 (6)	0.00333 (7)	−0.00218 (5)
O1	0.0153 (4)	0.0142 (3)	0.0163 (3)	−0.0001 (3)	0.0032 (3)	−0.0023 (3)
O2	0.0168 (4)	0.0168 (4)	0.0133 (3)	0.0006 (3)	0.0046 (3)	−0.0025 (3)
O3	0.0300 (5)	0.0146 (4)	0.0131 (3)	0.0039 (3)	0.0042 (3)	0.0011 (3)
C1	0.0176 (5)	0.0161 (5)	0.0159 (4)	−0.0025 (4)	0.0025 (4)	−0.0014 (4)
C2	0.0159 (5)	0.0127 (4)	0.0119 (4)	−0.0012 (4)	0.0030 (3)	0.0021 (3)
C3	0.0155 (5)	0.0164 (5)	0.0149 (5)	0.0012 (4)	0.0041 (4)	0.0010 (3)
C4	0.0190 (5)	0.0131 (4)	0.0121 (4)	0.0019 (4)	0.0064 (4)	0.0022 (4)
C5	0.0223 (5)	0.0177 (5)	0.0164 (4)	0.0049 (4)	0.0073 (4)	−0.0005 (4)

Geometric parameters (Å, º)

Zn1—O2	2.0319 (8)	C1—H1A	0.9800
Zn1—O2^i	2.0319 (8)	C1—H1B	0.9800
Zn1—O1	2.0491 (8)	C1—H1C	0.9800
Zn1—O1^i	2.0491 (8)	C2—C3	1.4122 (15)
Zn1—O3	2.1849 (8)	C3—C4	1.4088 (15)
Zn1—O3^i	2.1849 (8)	C3—H3	0.9500
O1—C2	1.2661 (14)	C4—C5	1.5114 (15)
O2—C4	1.2700 (14)	C5—H5A	0.9800
O3—H3A	0.79 (2)	C5—H5B	0.9800
O3—H3B	0.78 (2)	C5—H5C	0.9800
C1—C2	1.5125 (14)
O2—Zn1—O2^i	180.0	C2—C1—H1B	109.5
O2—Zn1—O1	90.53 (3)	H1A—C1—H1B	109.5
O2^i—Zn1—O1	89.47 (3)	C2—C1—H1C	109.5
O2—Zn1—O1^i	89.47 (3)	H1A—C1—H1C	109.5
O2^i—Zn1—O1^i	90.53 (3)	H1B—C1—H1C	109.5
O1—Zn1—O1^i	180.0	O1—C2—C3	125.89 (10)
O2—Zn1—O3	88.04 (3)	O1—C2—C1	116.06 (9)
O2^i—Zn1—O3	91.96 (3)	C3—C2—C1	118.06 (10)
O1—Zn1—O3	90.95 (3)	C4—C3—C2	125.73 (11)
O1^i—Zn1—O3	89.05 (3)	C4—C3—H3	117.1
O2—Zn1—O3^i	91.96 (3)	C2—C3—H3	117.1
O2^i—Zn1—O3^i	88.04 (3)	O2—C4—C3	125.86 (10)
O1—Zn1—O3^i	89.05 (3)	O2—C4—C5	115.70 (9)
O1^i—Zn1—O3^i	90.95 (3)	C3—C4—C5	118.44 (10)
O3—Zn1—O3^i	180.0	C4—C5—H5A	109.5
C2—O1—Zn1	123.34 (7)	C4—C5—H5B	109.5
C4—O2—Zn1	122.72 (7)	H5A—C5—H5B	109.5
Zn1—O3—H3A	125.0 (16)	C4—C5—H5C	109.5
Zn1—O3—H3B	125.9 (14)	H5A—C5—H5C	109.5
H3A—O3—H3B	109 (2)	H5B—C5—H5C	109.5
C2—C1—H1A	109.5
O2—Zn1—O1—C2	−21.26 (8)	Zn1—O1—C2—C3	10.79 (14)
O2^i—Zn1—O1—C2	158.74 (8)	Zn1—O1—C2—C1	−169.84 (7)
O3—Zn1—O1—C2	66.79 (8)	O1—C2—C3—C4	4.82 (18)
O3^i—Zn1—O1—C2	−113.21 (8)	C1—C2—C3—C4	−174.54 (10)
O1—Zn1—O2—C4	25.62 (8)	Zn1—O2—C4—C3	−20.11 (14)
O1^i—Zn1—O2—C4	−154.38 (8)	Zn1—O2—C4—C5	160.18 (7)
O3—Zn1—O2—C4	−65.32 (8)	C2—C3—C4—O2	0.46 (18)
O3^i—Zn1—O2—C4	114.68 (8)	C2—C3—C4—C5	−179.85 (10)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···O1^ii	0.79 (2)	2.09 (2)	2.8715 (12)	170 (2)
O3—H3B···O2^iii	0.78 (2)	2.122 (19)	2.8656 (11)	158.3 (19)

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