Retracted: μ-Oxido-bis­{chlorido[tris­(2-pyridylmeth­yl)amine]chromium(III)} bis(hexafluoridophosphate)

The title compound, [Cr₂Cl₂O(C₁₈H₁₈N₄)₂](PF₆)₂, is isostructural with the V^III analogue. Each Cr^III atom is chelated by the tetra­dentate tris­(2-pyridylmeth­yl)amine ligand via four N atoms, and further coordinated by one Cl atom and one bridging O atom, giving a slightly distorted octa­hedral coordination geometry. The dinuclear complex is centrosymmetric, with the bridging O atom lying on a centre of inversion.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.032
• wR factor = 0.089
• Data-to-parameter ratio = 13.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?
PLAT154_ALERT_1_C The su's on the Cell Angles are Equal  (x 10000)       3000 Deg.
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C16    -   C17     ..       5.96 su
PLAT231_ALERT_4_C Hirshfeld Test (Solvent)   P1     -   F6      ..       5.82 su
PLAT244_ALERT_4_C Low   'Solvent' Ueq as Compared to Neighbors for         P1

Alert level G
PLAT199_ALERT_1_G Check the Reported _cell_measurement_temperature        293 K
PLAT200_ALERT_1_G Check the Reported _diffrn_ambient_temperature .        293 K

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

   5 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
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

A classical but nevertheless rapidly developing field of application for related metal-Schiff compounds is their use as catalysts in polymerization, oxidation reactions, and model examples for the interaction of metal ions within the active sites of enzymes (Butler & Carrano, 1991; Crans et al., 1989; Dey, 1974; Chen & Zubieta, 1990). In the dinuclear title compound (Fig. 1), each Cr^III atom is chelated by the tetradentate ligand tris(2-pyridylmethyl)amine via four N atoms, and further coordinated by one Cl atom and one bridging O atom to give a slightly distorted octahedral coordination geometry.

Related literature

For the isostructural V^III analogue, see: Tajika et al. (2005). For more general related literature, see: Butler & Carrano (1991); Crans et al. (1989); Dey (1974); Chen & Zubieta (1990).

S2. Experimental

A mixture of chromium(III) trichloride (1 mmol) and tris(2-pyridylmethyl)amine (1 mmol) in 20 ml me thanol was refluxed for two hours. After cooling, the solution was filtered and the filtrate was evaporated naturally at room temperature. Blue blocks of the title compound were obtained after a few days with a yield of 31%. Elemental analysis calculated: C 40.39, H 3.35, N 10.44%; found: C 40.35, H 3.39, N 10.42%.

S3. Refinement

All H atoms were placed in calculated positions with C—H = 0.93 or 0.97 Å and refined as riding with U_iso(H) = 1.2U_eq(C).

Computing details

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL (Bruker, 2001).

Figures

Fig. 1. The molecular structure drawn with 30% probability displacement ellipsoids for the non-H atoms.

µ-Oxido-bis{chlorido[tris(2-pyridylmethyl)amine]chromium(III)} dihexafluoridophosphate

Crystal data

[Cr2Cl2O(C18H18N4)2](PF6)2	Z = 1
Mr = 1061.57	F(000) = 536
Triclinic, P1	Dx = 1.671 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.6107 (17) Å	Cell parameters from 3877 reflections
b = 11.302 (2) Å	θ = 3.0–25.5°
c = 12.798 (3) Å	µ = 0.81 mm^−1
α = 115.50 (3)°	T = 293 K
β = 107.45 (3)°	Block, blue
γ = 91.50 (3)°	0.28 × 0.22 × 0.18 mm
V = 1054.8 (4) Å^3

Data collection

Bruker APEX II CCD diffractometer	3877 independent reflections
Radiation source: fine-focus sealed tube	3594 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.021
φ and ω scans	θmax = 25.5°, θmin = 3.0°
Absorption correction: multi-scan (SADABS; Bruker, 2001)	h = −8→10
Tmin = 0.804, Tmax = 0.867	k = −13→13
8686 measured reflections	l = −15→15

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)] = 0.033	H-atom parameters constrained
wR(F^2) = 0.089	w = 1/[σ^2(Fo^2) + (0.0565P)^2 + 0.3428P] where P = (Fo^2 + 2Fc^2)/3
S = 1.00	(Δ/σ)max < 0.001
3877 reflections	Δρmax = 0.51 e Å^−3
287 parameters	Δρmin = −0.33 e Å^−3
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.042 (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	1.03745 (3)	0.34679 (3)	0.39271 (2)	0.0408 (4)
C1	0.9871 (3)	0.1897 (2)	0.53070 (18)	0.0447 (4)
H1	1.1018	0.1984	0.5573	0.054*
C2	0.8992 (3)	0.1306 (2)	0.5741 (2)	0.0534 (5)
H2	0.9533	0.0998	0.6296	0.064*
C3	0.7284 (3)	0.1173 (3)	0.5340 (2)	0.0605 (6)
H3	0.6662	0.0779	0.5626	0.073*
C4	0.6514 (3)	0.1630 (2)	0.4513 (2)	0.0552 (5)
H4	0.5367	0.1537	0.4226	0.066*
C5	0.7464 (2)	0.22306 (19)	0.41135 (18)	0.0425 (4)
C6	0.6721 (2)	0.2874 (2)	0.3310 (2)	0.0490 (5)
H6A	0.5643	0.2353	0.2730	0.059*
H6B	0.6563	0.3757	0.3822	0.059*
C7	0.7467 (3)	0.1753 (2)	0.1450 (2)	0.0573 (6)
H7A	0.7443	0.2004	0.0811	0.069*
H7B	0.6381	0.1253	0.1216	0.069*
C8	0.8712 (2)	0.08565 (19)	0.14924 (17)	0.0414 (4)
C9	0.8351 (3)	−0.0448 (2)	0.0588 (2)	0.0528 (5)
H9	0.7315	−0.0793	−0.0028	0.063*
C10	0.9546 (3)	−0.1237 (2)	0.0606 (2)	0.0617 (6)
H10	0.9327	−0.2119	0.0003	0.074*
C11	1.1069 (3)	−0.0697 (2)	0.1532 (2)	0.0607 (6)
H11	1.1894	−0.1208	0.1564	0.073*
C12	1.1346 (3)	0.0605 (2)	0.2404 (2)	0.0526 (5)
H12	1.2374	0.0964	0.3028	0.063*
C13	0.7605 (3)	0.4147 (2)	0.23723 (19)	0.0475 (5)
H13A	0.7430	0.4881	0.3059	0.057*
H13B	0.6651	0.3917	0.1639	0.057*
C14	0.9146 (3)	0.4574 (2)	0.21891 (17)	0.0471 (5)
C15	0.9138 (4)	0.5296 (2)	0.1547 (2)	0.0606 (6)
H15	0.8154	0.5482	0.1149	0.073*
C16	1.0629 (4)	0.5734 (3)	0.1512 (2)	0.0728 (8)
H16	1.0650	0.6237	0.1100	0.087*
C17	1.2075 (4)	0.5435 (3)	0.2077 (3)	0.0715 (7)
H17	1.3076	0.5721	0.2047	0.086*
C18	1.2007 (3)	0.4704 (3)	0.2686 (2)	0.0610 (6)
H18	1.2978	0.4490	0.3069	0.073*
Cl1	1.31398 (6)	0.35078 (6)	0.48445 (5)	0.05507 (17)
F1	0.5115 (2)	0.90789 (16)	0.13882 (17)	0.0825 (5)
F2	0.4878 (2)	0.8490 (2)	0.27945 (15)	0.0893 (5)
F3	0.5830 (3)	0.6607 (2)	0.1912 (2)	0.1078 (7)
F4	0.7325 (2)	0.8610 (2)	0.24906 (17)	0.0999 (6)
F5	0.6040 (2)	0.72005 (19)	0.04870 (17)	0.0929 (6)
F6	0.36012 (19)	0.71102 (16)	0.08031 (14)	0.0726 (4)
N1	1.0192 (2)	0.13917 (16)	0.23969 (15)	0.0436 (4)
N2	1.0566 (2)	0.42848 (18)	0.27454 (16)	0.0482 (4)
N3	0.91312 (19)	0.23567 (15)	0.45104 (15)	0.0406 (3)
N4	0.7776 (2)	0.29834 (16)	0.26214 (15)	0.0424 (4)
O1	1.0000	0.5000	0.5000	0.0420 (4)
P1	0.54870 (7)	0.78424 (6)	0.16549 (5)	0.05276 (17)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cr1	0.0378 (11)	0.0424 (10)	0.0424 (10)	0.0088 (8)	0.0112 (8)	0.0212 (8)
C1	0.0415 (10)	0.0468 (10)	0.0459 (10)	0.0095 (8)	0.0121 (8)	0.0233 (8)
C2	0.0597 (14)	0.0546 (12)	0.0513 (12)	0.0109 (10)	0.0179 (10)	0.0300 (10)
C3	0.0606 (14)	0.0666 (14)	0.0669 (14)	0.0057 (11)	0.0281 (11)	0.0381 (12)
C4	0.0395 (11)	0.0606 (13)	0.0695 (14)	0.0063 (9)	0.0206 (10)	0.0324 (11)
C5	0.0351 (9)	0.0412 (9)	0.0456 (10)	0.0057 (7)	0.0117 (8)	0.0166 (8)
C6	0.0302 (9)	0.0572 (12)	0.0614 (12)	0.0093 (8)	0.0107 (8)	0.0322 (10)
C7	0.0517 (13)	0.0499 (12)	0.0462 (11)	0.0099 (9)	−0.0011 (9)	0.0127 (9)
C8	0.0424 (10)	0.0438 (10)	0.0403 (9)	0.0052 (8)	0.0153 (8)	0.0207 (8)
C9	0.0562 (13)	0.0484 (11)	0.0497 (11)	0.0027 (9)	0.0185 (10)	0.0189 (9)
C10	0.0769 (17)	0.0441 (11)	0.0634 (14)	0.0138 (11)	0.0334 (13)	0.0178 (10)
C11	0.0653 (15)	0.0551 (13)	0.0714 (15)	0.0256 (11)	0.0342 (12)	0.0297 (11)
C12	0.0460 (12)	0.0572 (12)	0.0570 (12)	0.0167 (9)	0.0199 (10)	0.0265 (10)
C13	0.0504 (11)	0.0490 (11)	0.0410 (10)	0.0162 (9)	0.0097 (8)	0.0224 (9)
C14	0.0599 (13)	0.0426 (10)	0.0358 (9)	0.0112 (9)	0.0152 (9)	0.0162 (8)
C15	0.0864 (18)	0.0503 (12)	0.0451 (12)	0.0140 (11)	0.0197 (11)	0.0237 (10)
C16	0.114 (2)	0.0544 (13)	0.0572 (14)	0.0012 (14)	0.0362 (15)	0.0288 (12)
C17	0.084 (2)	0.0710 (16)	0.0683 (16)	−0.0005 (14)	0.0357 (14)	0.0343 (13)
C18	0.0612 (14)	0.0666 (14)	0.0615 (14)	0.0042 (11)	0.0280 (11)	0.0307 (12)
Cl1	0.0334 (3)	0.0609 (3)	0.0596 (3)	0.0131 (2)	0.0101 (2)	0.0215 (2)
F1	0.0810 (11)	0.0724 (10)	0.0988 (12)	0.0060 (8)	0.0208 (9)	0.0507 (9)
F2	0.0836 (12)	0.1141 (14)	0.0632 (9)	0.0059 (10)	0.0336 (8)	0.0300 (9)
F3	0.1008 (15)	0.1236 (16)	0.163 (2)	0.0524 (12)	0.0641 (14)	0.1074 (16)
F4	0.0483 (9)	0.1549 (19)	0.0854 (12)	−0.0063 (10)	0.0024 (8)	0.0605 (12)
F5	0.0973 (13)	0.0965 (12)	0.0873 (12)	0.0083 (10)	0.0563 (10)	0.0288 (10)
F6	0.0571 (9)	0.0710 (9)	0.0731 (9)	−0.0042 (7)	0.0144 (7)	0.0248 (7)
N1	0.0425 (9)	0.0456 (9)	0.0444 (9)	0.0116 (7)	0.0164 (7)	0.0210 (7)
N2	0.0526 (10)	0.0497 (9)	0.0451 (9)	0.0087 (8)	0.0187 (8)	0.0231 (8)
N3	0.0348 (8)	0.0421 (8)	0.0447 (8)	0.0082 (6)	0.0125 (7)	0.0205 (7)
N4	0.0376 (8)	0.0442 (8)	0.0411 (8)	0.0101 (7)	0.0077 (6)	0.0195 (7)
O1	0.0384 (10)	0.0430 (10)	0.0424 (10)	0.0081 (8)	0.0119 (8)	0.0190 (8)
P1	0.0429 (3)	0.0665 (4)	0.0529 (3)	0.0075 (3)	0.0151 (2)	0.0321 (3)

Geometric parameters (Å, º)

Cr1—O1	1.7986 (7)	C9—H9	0.930
Cr1—N3	2.1206 (18)	C10—C11	1.378 (4)
Cr1—N2	2.1238 (18)	C10—H10	0.930
Cr1—N4	2.2370 (19)	C11—C12	1.370 (3)
Cr1—N1	2.2814 (19)	C11—H11	0.930
Cr1—Cl1	2.3070 (9)	C12—N1	1.351 (3)
O1—Cr1^i	1.7986 (7)	C12—H12	0.930
C1—N3	1.341 (3)	C13—N4	1.482 (3)
C1—C2	1.369 (3)	C13—C14	1.516 (3)
C1—H1	0.930	C13—H13A	0.970
C2—C3	1.386 (4)	C13—H13B	0.970
C2—H2	0.930	C14—N2	1.345 (3)
C3—C4	1.376 (4)	C14—C15	1.383 (3)
C3—H3	0.930	C15—C16	1.384 (4)
C4—C5	1.382 (3)	C15—H15	0.930
C4—H4	0.930	C16—C17	1.371 (4)
C5—N3	1.352 (3)	C16—H16	0.930
C5—C6	1.506 (3)	C17—C18	1.369 (4)
C6—N4	1.479 (3)	C17—H17	0.930
C6—H6A	0.970	C18—N2	1.351 (3)
C6—H6B	0.970	C18—H18	0.930
C7—N4	1.483 (3)	F1—P1	1.5939 (17)
C7—C8	1.499 (3)	F2—P1	1.5803 (18)
C7—H7A	0.970	F3—P1	1.582 (2)
C7—H7B	0.970	F4—P1	1.5859 (18)
C8—N1	1.342 (3)	F5—P1	1.5804 (18)
C8—C9	1.379 (3)	F6—P1	1.6129 (17)
C9—C10	1.380 (4)
O1—Cr1—N3	91.01 (5)	N1—C12—H12	118.5
O1—Cr1—N2	92.46 (5)	C11—C12—H12	118.5
N3—Cr1—N2	154.67 (7)	N4—C13—C14	110.48 (16)
O1—Cr1—N4	91.36 (6)	N4—C13—H13A	109.6
N3—Cr1—N4	78.03 (7)	C14—C13—H13A	109.6
N2—Cr1—N4	76.81 (7)	N4—C13—H13B	109.6
O1—Cr1—N1	166.58 (5)	C14—C13—H13B	109.6
N3—Cr1—N1	81.87 (7)	H13A—C13—H13B	108.1
N2—Cr1—N1	89.30 (7)	N2—C14—C15	120.7 (2)
N4—Cr1—N1	76.09 (7)	N2—C14—C13	116.67 (18)
O1—Cr1—Cl1	103.29 (5)	C15—C14—C13	122.5 (2)
N3—Cr1—Cl1	104.03 (5)	C14—C15—C16	118.4 (3)
N2—Cr1—Cl1	99.56 (6)	C14—C15—H15	120.8
N4—Cr1—Cl1	165.11 (5)	C16—C15—H15	120.8
N1—Cr1—Cl1	89.52 (6)	C17—C16—C15	120.8 (2)
N3—C1—C2	122.1 (2)	C17—C16—H16	119.6
N3—C1—H1	118.9	C15—C16—H16	119.6
C2—C1—H1	119.0	C16—C17—C18	118.2 (3)
C3—C2—C1	118.8 (2)	C16—C17—H17	120.9
C3—C2—H2	120.6	C18—C17—H17	120.9
C1—C2—H2	120.6	N2—C18—C17	121.8 (3)
C2—C3—C4	119.4 (2)	N2—C18—H18	119.1
C2—C3—H3	120.3	C17—C18—H18	119.1
C4—C3—H3	120.3	C12—N1—C8	117.79 (18)
C3—C4—C5	119.3 (2)	C12—N1—Cr1	126.02 (15)
C3—C4—H4	120.4	C8—N1—Cr1	115.61 (13)
C5—C4—H4	120.4	C14—N2—C18	120.1 (2)
N3—C5—C4	120.95 (19)	C14—N2—Cr1	114.45 (14)
N3—C5—C6	116.79 (18)	C18—N2—Cr1	124.62 (17)
C4—C5—C6	122.07 (19)	C1—N3—C5	119.42 (18)
N4—C6—C5	112.19 (16)	C1—N3—Cr1	125.22 (14)
N4—C6—H6A	109.2	C5—N3—Cr1	115.07 (13)
C5—C6—H6A	109.2	C6—N4—C7	112.30 (18)
N4—C6—H6B	109.2	C6—N4—C13	112.63 (16)
C5—C6—H6B	109.2	C7—N4—C13	109.74 (17)
H6A—C6—H6B	107.9	C6—N4—Cr1	105.11 (12)
N4—C7—C8	114.97 (17)	C7—N4—Cr1	112.78 (13)
N4—C7—H7A	108.5	C13—N4—Cr1	103.96 (12)
C8—C7—H7A	108.5	Cr1—O1—Cr1^i	180.0
N4—C7—H7B	108.5	F5—P1—F3	90.59 (12)
C8—C7—H7B	108.5	F5—P1—F2	178.06 (11)
H7A—C7—H7B	107.5	F3—P1—F2	90.59 (13)
N1—C8—C9	122.2 (2)	F5—P1—F4	90.15 (11)
N1—C8—C7	117.57 (17)	F3—P1—F4	91.62 (13)
C9—C8—C7	120.13 (19)	F2—P1—F4	91.35 (11)
C10—C9—C8	119.3 (2)	F5—P1—F1	89.58 (11)
C10—C9—H9	120.4	F3—P1—F1	179.22 (11)
C8—C9—H9	120.4	F2—P1—F1	89.22 (11)
C11—C10—C9	118.9 (2)	F4—P1—F1	89.14 (11)
C11—C10—H10	120.5	F5—P1—F6	90.19 (10)
C9—C10—H10	120.5	F3—P1—F6	90.39 (12)
C10—C11—C12	118.9 (2)	F2—P1—F6	88.26 (10)
C10—C11—H11	120.6	F4—P1—F6	177.95 (11)
C12—C11—H11	120.6	F1—P1—F6	88.85 (10)
N1—C12—C11	122.9 (2)

Symmetry code: (i) −x+2, −y+1, −z+1.