cis-Bis(acetyl­acetonato)diaqua­chromium(III) perchlorate monohydrate

The Cr³⁺ center of the cation present in the title compound, [Cr(C₅H₇O₂)₂(H₂O)₂]ClO₄·H₂O, assumes a pseudo-octa­hedral geometry. The uncoordinated water mol­ecule and the perchlorate anion are involved in moderately strong O—H...O hydrogen-bonding inter­actions with the cation, resulting in a three-dimensional network.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.005 Å
• R factor = 0.048
• wR factor = 0.158
• Data-to-parameter ratio = 17.6

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          6

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Cr1         (4)       4.03
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......         10

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

Our interest in the title compound, (I), stems from its usefulness as a starting material for the synthesis of mixed ligand bis(acetylacetonato)Cr(III)-amino acidato complexes. We have obtained crystals of (I) as the major product together with the trans isomer from a modified literature procedure (Ogino et al., 1988).

In compound (I), two acetylacetonato ligands and two water molecules bind the Cr³⁺ center conferring pseudo-octahedral geometry to the metal ion (Fig. 1). The ions and the solvated water molecules are linked through hydrogen bonding. The hydrogen bonding interaction between the ions gives rise to a three-dimensional network as shown in Fig. 2.

Specifically, one of the coordinated water molecules (O1W) is hydrogen bonded to the solvated water molecule (O3W), whereas the other (O2W) is hydrogen bonded to a perchlorate O atom (O7). Each of the two water molecules is hydrogen bonded to a coordinated acetylacetonato anion through one of the O atoms of the latter ligand. In addition, the solvated water molecule (O3W) is also involved in a moderately strong hydrogen bonding with one of the perchlorate O atoms (O8).

Unlike in the structure of the corresponding tetrafluroborate salt (Nakano et al., 2003), the anion in (I) is ordered, possibly a consequence of the hydrogen bonds. The Cr—O_acac bonds are only slightly shorter (ca 0.06 Å) than the two Cr—O_aqua bonds indicating strong bonds with the water molecules as observed in the trans-bis(malonato)(diaqua)chromium(III) (Lemmer et al., 2002) and cis-bis(oxalato)diaquachromium(III) cations (Marinescu et al., 2002).

Related literature

For synthesis, see: Ogino et al. (1988). Structural features observed for the cation in (I) are comparable to those reported for the cation in the corresponding tetrafluoroborate salt (Nakano et al., 2003). For related literature, see: Lemmer et al. (2002); Marinescu et al. (2002)

S2. Experimental

Compound (I) was obtained by the ligand exchange reaction of [Cr(acac)₃] with water in the presene of perchloric acid by a modified literature procedure (Ogino et al., 1988), as follows: To a suspension of [Cr(acac)₃] (6.981 g, 20 mmol) in water (200 ml) were added a solution of HClO₄ (3 ml, 70% w/v) in water (50 ml) and ethanol (95%, 50 ml). The mixture was allowed to reflux for 5 d. The reaction mixture was treated following the literature method, rotary evaporated to ca 15 ml and allowed to stand at room temperature overnight. The cis and trans isomers of the complex crystallized as large purple and brown-purple rectangular prisms, respectively. A purple crystal of suitable size was chosen for the X-ray diffraction studies.

S3. Refinement

The water H atoms were located and refined, with the O—H and H···H distances restrained to 0.84 (1) and 1.37 (2) Å, respectively, and with U_iso(H) = 1.5U_eq(O). Other H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93–0.96 Å and U_iso(H) = 1.2–1.5U_eq(C).

Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXTL (Sheldrick, 2004b); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Figures

	Fig. 1. The asymmetric unit of (I), with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres with arbitrary radii. Hydrogen bonds are represented by dashed lines.
	Fig. 2. The crystal packing of (I), viewed down the a axis.

cis-Bis(acetylacetonato)diaquachromium(III) perchlorate monohydrate

Crystal data

[Cr(C5H7O2)2(H2O)2]ClO4·H2O	F(000) = 836
Mr = 403.71	Dx = 1.515 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 8910 reflections
a = 9.9811 (3) Å	θ = 2.2–24.4°
b = 14.8470 (5) Å	µ = 0.85 mm^−1
c = 12.0093 (4) Å	T = 296 K
β = 96.036 (2)°	Rectangular prism, purple
V = 1769.78 (10) Å^3	0.38 × 0.24 × 0.12 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer	4051 independent reflections
Radiation source: fine-focus sealed tube	2771 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.047
φ and ω scans	θmax = 27.5°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2004a)	h = −12→12
Tmin = 0.776, Tmax = 0.894	k = −19→19
38774 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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.158	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	w = 1/[σ^2(Fo^2) + (0.0777P)^2 + 0.8712P] where P = (Fo^2 + 2Fc^2)/3
4051 reflections	(Δ/σ)max = 0.013
230 parameters	Δρmax = 0.64 e Å^−3
10 restraints	Δρmin = −0.48 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
Cr1	0.24915 (4)	0.50161 (3)	0.49777 (3)	0.03861 (17)
O1	0.11295 (17)	0.46012 (14)	0.38113 (17)	0.0464 (5)
O1W	0.38847 (19)	0.54583 (18)	0.61600 (18)	0.0569 (6)
H1WA	0.4639 (19)	0.560 (3)	0.598 (3)	0.085*
H1WB	0.387 (3)	0.547 (3)	0.6849 (10)	0.085*
O2	0.32828 (19)	0.58155 (14)	0.39606 (17)	0.0495 (5)
O2W	0.1230 (2)	0.59873 (14)	0.5386 (2)	0.0586 (6)
H2WA	0.048 (2)	0.587 (2)	0.558 (3)	0.088*
H2WB	0.137 (3)	0.6545 (8)	0.541 (4)	0.088*
O3	0.17123 (19)	0.42715 (13)	0.60618 (16)	0.0461 (5)
O4	0.36654 (18)	0.40495 (13)	0.45914 (16)	0.0431 (4)
C1	0.0035 (4)	0.4301 (3)	0.2014 (3)	0.0719 (10)
H1A	0.0191	0.3663	0.2049	0.108*
H1B	0.0050	0.4505	0.1257	0.108*
H1C	−0.0829	0.4432	0.2261	0.108*
C2	0.1115 (3)	0.4776 (2)	0.2757 (3)	0.0509 (7)
C3	0.1994 (3)	0.5354 (2)	0.2309 (3)	0.0595 (8)
H3	0.1903	0.5414	0.1534	0.071*
C4	0.3003 (3)	0.5857 (2)	0.2903 (3)	0.0510 (7)
C5	0.3840 (4)	0.6505 (3)	0.2314 (3)	0.0771 (11)
H5A	0.3634	0.7110	0.2521	0.116*
H5B	0.3643	0.6433	0.1519	0.116*
H5C	0.4777	0.6386	0.2525	0.116*
C6	0.1033 (4)	0.3005 (2)	0.7020 (3)	0.0628 (9)
H6A	0.1092	0.3371	0.7682	0.094*
H6B	0.1378	0.2415	0.7208	0.094*
H6C	0.0110	0.2960	0.6710	0.094*
C7	0.1845 (3)	0.3426 (2)	0.6179 (2)	0.0441 (6)
C8	0.2686 (3)	0.2903 (2)	0.5606 (3)	0.0556 (8)
H8	0.2665	0.2285	0.5726	0.067*
C9	0.3560 (3)	0.3215 (2)	0.4869 (2)	0.0473 (7)
C10	0.4473 (4)	0.2596 (2)	0.4342 (4)	0.0744 (11)
H10A	0.4384	0.2694	0.3548	0.112*
H10B	0.4239	0.1984	0.4493	0.112*
H10C	0.5387	0.2708	0.4644	0.112*
Cl1	0.18174 (9)	0.84694 (6)	0.48642 (9)	0.0702 (3)
O5	0.2817 (4)	0.9075 (2)	0.5349 (3)	0.1088 (11)
O6	0.2096 (5)	0.8157 (3)	0.3860 (4)	0.166 (2)
O7	0.1774 (5)	0.7744 (2)	0.5643 (4)	0.1472 (16)
O8	0.0575 (4)	0.8874 (4)	0.4839 (4)	0.177 (2)
O3W	0.3564 (3)	0.5459 (2)	0.8294 (2)	0.0920 (9)
H3WB	0.348 (5)	0.4912 (10)	0.847 (2)	0.138*
H3WA	0.428 (3)	0.565 (3)	0.864 (4)	0.138*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cr1	0.0244 (2)	0.0459 (3)	0.0472 (3)	−0.00116 (17)	0.01153 (18)	0.00286 (19)
O1	0.0274 (9)	0.0551 (12)	0.0573 (12)	−0.0027 (8)	0.0070 (8)	−0.0001 (9)
O1W	0.0329 (10)	0.0875 (16)	0.0521 (12)	−0.0158 (11)	0.0127 (9)	−0.0069 (12)
O2	0.0368 (10)	0.0561 (12)	0.0571 (13)	−0.0065 (9)	0.0117 (9)	0.0097 (10)
O2W	0.0368 (11)	0.0475 (12)	0.0960 (17)	−0.0007 (9)	0.0283 (11)	−0.0014 (12)
O3	0.0376 (10)	0.0508 (11)	0.0534 (11)	−0.0018 (9)	0.0205 (8)	0.0026 (9)
O4	0.0293 (9)	0.0504 (11)	0.0523 (11)	0.0028 (8)	0.0172 (8)	0.0012 (9)
C1	0.060 (2)	0.091 (3)	0.064 (2)	−0.0085 (19)	0.0011 (17)	−0.0121 (19)
C2	0.0413 (15)	0.0593 (18)	0.0526 (17)	0.0090 (14)	0.0065 (13)	−0.0069 (14)
C3	0.061 (2)	0.069 (2)	0.0494 (17)	−0.0020 (17)	0.0136 (15)	0.0018 (16)
C4	0.0449 (16)	0.0539 (17)	0.0573 (18)	0.0074 (14)	0.0198 (14)	0.0097 (14)
C5	0.072 (2)	0.088 (3)	0.075 (2)	−0.008 (2)	0.0251 (19)	0.023 (2)
C6	0.066 (2)	0.065 (2)	0.0618 (19)	−0.0130 (17)	0.0282 (16)	0.0053 (16)
C7	0.0377 (14)	0.0511 (17)	0.0449 (15)	−0.0059 (12)	0.0105 (11)	0.0021 (12)
C8	0.0567 (18)	0.0443 (16)	0.070 (2)	−0.0022 (14)	0.0236 (15)	−0.0010 (14)
C9	0.0352 (14)	0.0525 (17)	0.0547 (17)	0.0007 (13)	0.0078 (12)	−0.0051 (14)
C10	0.066 (2)	0.059 (2)	0.104 (3)	0.0101 (18)	0.040 (2)	−0.012 (2)
Cl1	0.0608 (5)	0.0566 (5)	0.0930 (7)	0.0043 (4)	0.0079 (4)	−0.0052 (5)
O5	0.121 (3)	0.087 (2)	0.115 (2)	−0.035 (2)	0.000 (2)	−0.0070 (18)
O6	0.173 (4)	0.198 (4)	0.139 (3)	−0.079 (4)	0.076 (3)	−0.095 (3)
O7	0.197 (4)	0.081 (2)	0.160 (4)	−0.048 (3)	0.000 (3)	0.008 (2)
O8	0.113 (3)	0.242 (5)	0.169 (4)	0.100 (4)	−0.016 (3)	−0.030 (4)
O3W	0.097 (2)	0.119 (2)	0.0580 (15)	−0.0363 (19)	−0.0006 (14)	0.0106 (16)

Geometric parameters (Å, º)

Cr1—O2	1.9306 (19)	C4—C5	1.499 (4)
Cr1—O3	1.9327 (19)	C5—H5A	0.96
Cr1—O4	1.9396 (19)	C5—H5B	0.96
Cr1—O1	1.947 (2)	C5—H5C	0.96
Cr1—O1W	1.991 (2)	C6—C7	1.496 (4)
Cr1—O2W	2.009 (2)	C6—H6A	0.96
O1—C2	1.291 (4)	C6—H6B	0.96
O1W—H1WA	0.833 (10)	C6—H6C	0.96
O1W—H1WB	0.829 (10)	C7—C8	1.379 (4)
O2—C4	1.272 (4)	C8—C9	1.387 (4)
O2W—H2WA	0.830 (10)	C8—H8	0.93
O2W—H2WB	0.839 (10)	C9—C10	1.483 (4)
O3—C7	1.269 (3)	C10—H10A	0.96
O4—C9	1.290 (3)	C10—H10B	0.96
C1—C2	1.502 (5)	C10—H10C	0.96
C1—H1A	0.96	Cl1—O6	1.348 (4)
C1—H1B	0.96	Cl1—O8	1.375 (4)
C1—H1C	0.96	Cl1—O5	1.421 (3)
C2—C3	1.376 (4)	Cl1—O7	1.430 (4)
C3—C4	1.389 (5)	O3W—H3WA	0.84 (4)
C3—H3	0.93	O3W—H3WB	0.84 (1)
O2—Cr1—O3	176.62 (8)	O2—C4—C3	123.9 (3)
O2—Cr1—O4	90.34 (8)	O2—C4—C5	115.3 (3)
O3—Cr1—O4	91.94 (8)	C3—C4—C5	120.8 (3)
O2—Cr1—O1	92.32 (9)	C4—C5—H5A	109.5
O3—Cr1—O1	90.21 (9)	C4—C5—H5B	109.5
O4—Cr1—O1	89.28 (8)	H5A—C5—H5B	109.5
O2—Cr1—O1W	86.96 (9)	C4—C5—H5C	109.5
O3—Cr1—O1W	90.49 (9)	H5A—C5—H5C	109.5
O4—Cr1—O1W	91.17 (9)	H5B—C5—H5C	109.5
O1—Cr1—O1W	179.15 (9)	C7—C6—H6A	109.5
O2—Cr1—O2W	91.26 (9)	C7—C6—H6B	109.5
O3—Cr1—O2W	86.51 (9)	H6A—C6—H6B	109.5
O4—Cr1—O2W	178.13 (8)	C7—C6—H6C	109.5
O1—Cr1—O2W	89.69 (10)	H6A—C6—H6C	109.5
O1W—Cr1—O2W	89.88 (10)	H6B—C6—H6C	109.5
C2—O1—Cr1	125.23 (19)	O3—C7—C8	124.3 (3)
Cr1—O1W—H1WA	119 (2)	O3—C7—C6	115.5 (3)
Cr1—O1W—H1WB	129 (2)	C8—C7—C6	120.2 (3)
H1WA—O1W—H1WB	111.2 (17)	C7—C8—C9	126.0 (3)
C4—O2—Cr1	126.8 (2)	C7—C8—H8	117.0
Cr1—O2W—H2WA	122 (2)	C9—C8—H8	117.0
Cr1—O2W—H2WB	128 (2)	O4—C9—C8	124.0 (3)
H2WA—O2W—H2WB	110.0 (17)	O4—C9—C10	114.5 (3)
C7—O3—Cr1	126.59 (18)	C8—C9—C10	121.4 (3)
C9—O4—Cr1	125.53 (17)	C9—C10—H10A	109.5
C2—C1—H1A	109.5	C9—C10—H10B	109.5
C2—C1—H1B	109.5	H10A—C10—H10B	109.5
H1A—C1—H1B	109.5	C9—C10—H10C	109.5
C2—C1—H1C	109.5	H10A—C10—H10C	109.5
H1A—C1—H1C	109.5	H10B—C10—H10C	109.5
H1B—C1—H1C	109.5	O6—Cl1—O8	113.7 (3)
O1—C2—C3	124.5 (3)	O6—Cl1—O5	112.4 (2)
O1—C2—C1	115.0 (3)	O8—Cl1—O5	109.0 (3)
C3—C2—C1	120.5 (3)	O6—Cl1—O7	110.5 (3)
C2—C3—C4	126.3 (3)	O8—Cl1—O7	104.7 (4)
C2—C3—H3	116.9	O5—Cl1—O7	106.1 (2)
C4—C3—H3	116.9	H3WB—O3W—H3WA	108 (2)
O2—Cr1—O1—C2	9.8 (2)	Cr1—O1—C2—C3	−6.5 (4)
O3—Cr1—O1—C2	−172.5 (2)	Cr1—O1—C2—C1	174.1 (2)
O4—Cr1—O1—C2	−80.6 (2)	O1—C2—C3—C4	−1.8 (5)
O2W—Cr1—O1—C2	101.0 (2)	C1—C2—C3—C4	177.6 (3)
O4—Cr1—O2—C4	80.5 (2)	Cr1—O2—C4—C3	4.3 (4)
O1—Cr1—O2—C4	−8.8 (2)	Cr1—O2—C4—C5	−176.3 (2)
O1W—Cr1—O2—C4	171.7 (2)	C2—C3—C4—O2	3.1 (5)
O2W—Cr1—O2—C4	−98.5 (2)	C2—C3—C4—C5	−176.3 (3)
O4—Cr1—O3—C7	−12.1 (2)	Cr1—O3—C7—C8	6.4 (4)
O1—Cr1—O3—C7	77.2 (2)	Cr1—O3—C7—C6	−174.8 (2)
O1W—Cr1—O3—C7	−103.3 (2)	O3—C7—C8—C9	3.7 (5)
O2W—Cr1—O3—C7	166.8 (2)	C6—C7—C8—C9	−175.1 (3)
O2—Cr1—O4—C9	−169.5 (2)	Cr1—O4—C9—C8	−8.3 (4)
O3—Cr1—O4—C9	13.0 (2)	Cr1—O4—C9—C10	172.3 (2)
O1—Cr1—O4—C9	−77.2 (2)	C7—C8—C9—O4	−2.5 (5)
O1W—Cr1—O4—C9	103.5 (2)	C7—C8—C9—C10	176.8 (3)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1W—H1WA···O4^i	0.83 (1)	1.96 (2)	2.791 (3)	174 (3)
O1W—H1WB···O3W	0.83 (1)	1.79 (1)	2.616 (3)	171 (3)
O2W—H2WA···O1^ii	0.83 (1)	1.96 (2)	2.778 (3)	169 (3)
O2W—H2WB···O7	0.84 (1)	1.84 (1)	2.675 (4)	173 (4)
O3W—H3WA···O8^iii	0.84 (4)	1.96 (2)	2.770 (5)	161 (6)

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x, −y+1, −z+1; (iii) x+1/2, −y+3/2, z+1/2.