Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270106041783/gz3045sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270106041783/gz3045Isup2.hkl |
CCDC reference: 632911
Complex (I) (0.210 g; 0.316 mmol) in 20 ml of THF was cooled to 243 K. To the slurry was added ZnMe2 (0.058 g) and the solution was allowed to warm to room temperature. After stirring overnight, the reaction mixture was filtered, concentrated and cooled to 243 K overnight to yield colorless crystals of complex (II) in 62% yield.
The molecule is located at an inversion center. The heavy-atom bond framework shows significant differences in the component anisotropic displacement parameters along the bonding directions, perhaps because of insufficient absorption corrections. Numerical corrections were unsatisfactory because of indeterminate crystal faces. The results presented represent the best of several attempts at multi-scan absorption corrections. H atoms were assigned calculated positions (C—H = 0.98 and 0.98 Å) with constrained Uiso(H) values of 1.2–1.5 times Ueq(C).
Data collection: SMART (Bruker, 2002); cell refinement: SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 2001); software used to prepare material for publication: SHELXTL.
Fig. 1. The molecular structure of (II), with ellipsoids depicted at 50% probability. H atoms have been omitted for clarity. [Symmetry code: (i) −x, 2 − y, −z.] |
[CrZn2(CH3)2Cl4(C4H8O)4] | Z = 1 |
Mr = 643.02 | F(000) = 330 |
Triclinic, P1 | Dx = 1.616 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 7.8530 (14) Å | Cell parameters from 980 reflections |
b = 8.8695 (16) Å | θ = 2.8–28.0° |
c = 10.7901 (19) Å | µ = 2.63 mm−1 |
α = 68.759 (2)° | T = 120 K |
β = 71.741 (2)° | Block, colourless |
γ = 77.434 (2)° | 0.10 × 0.06 × 0.04 mm |
V = 660.6 (2) Å3 |
Bruker APEX diffractometer | 2938 independent reflections |
Radiation source: fine-focus sealed tube | 2794 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.016 |
Detector resolution: 836.6 pixels mm-1 | θmax = 28.2°, θmin = 2.1° |
ω scans | h = −10→9 |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | k = −11→11 |
Tmin = 0.779, Tmax = 0.902 | l = −14→14 |
7317 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.023 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.059 | H-atom parameters constrained |
S = 1.03 | w = 1/[σ2(Fo2) + (0.0337P)2 + 0.2798P] where P = (Fo2 + 2Fc2)/3 |
2938 reflections | (Δ/σ)max = 0.001 |
134 parameters | Δρmax = 0.36 e Å−3 |
1 restraint | Δρmin = −0.22 e Å−3 |
[CrZn2(CH3)2Cl4(C4H8O)4] | γ = 77.434 (2)° |
Mr = 643.02 | V = 660.6 (2) Å3 |
Triclinic, P1 | Z = 1 |
a = 7.8530 (14) Å | Mo Kα radiation |
b = 8.8695 (16) Å | µ = 2.63 mm−1 |
c = 10.7901 (19) Å | T = 120 K |
α = 68.759 (2)° | 0.10 × 0.06 × 0.04 mm |
β = 71.741 (2)° |
Bruker APEX diffractometer | 2938 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | 2794 reflections with I > 2σ(I) |
Tmin = 0.779, Tmax = 0.902 | Rint = 0.016 |
7317 measured reflections |
R[F2 > 2σ(F2)] = 0.023 | 1 restraint |
wR(F2) = 0.059 | H-atom parameters constrained |
S = 1.03 | Δρmax = 0.36 e Å−3 |
2938 reflections | Δρmin = −0.22 e Å−3 |
134 parameters |
Experimental. Data collection is performed with four batch runs at ϕ = 0.00 ° (600 frames), at ϕ = 90.00 ° (600 frames), at ϕ = 180 ° (600 frames) and at ϕ = 270 ° (600 frames). Frame width = 0.30 \& in ω. Data is merged, corrected for decay, and treated with multi-scan absorption corrections. |
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. The highest unassigned peak is located 0.71 (1) Å from atom C3. The deepest electron density hole is located 0.26 (1) Å from atom H2B. All structure factors are from the SHELXTL program libary (Sheldrick, 2001). |
x | y | z | Uiso*/Ueq | ||
Zn1 | 0.12951 (3) | 0.91456 (2) | 0.301086 (19) | 0.01957 (7) | |
Cr1 | 0.0000 | 1.0000 | 0.0000 | 0.01439 (9) | |
Cl1 | −0.10738 (5) | 1.09447 (5) | 0.22835 (4) | 0.01946 (9) | |
Cl2 | 0.26459 (5) | 0.85785 (5) | 0.08810 (4) | 0.01968 (9) | |
O1 | 0.13570 (15) | 1.20042 (14) | −0.11310 (12) | 0.0195 (2) | |
O2 | 0.29183 (18) | 1.08799 (15) | 0.27424 (13) | 0.0241 (3) | |
C1 | 0.1294 (3) | 0.7330 (2) | 0.47226 (19) | 0.0300 (4) | |
H1A | 0.0541 | 0.7682 | 0.5507 | 0.045* | |
H1B | 0.2531 | 0.6985 | 0.4819 | 0.045* | |
H1C | 0.0808 | 0.6417 | 0.4697 | 0.045* | |
C2 | 0.3185 (2) | 1.1955 (2) | −0.2030 (2) | 0.0273 (4) | |
H2A | 0.3268 | 1.1417 | −0.2710 | 0.033* | |
H2B | 0.4067 | 1.1346 | −0.1485 | 0.033* | |
C3 | 0.3558 (3) | 1.3703 (2) | −0.2748 (2) | 0.0294 (4) | |
H3A | 0.3391 | 1.4092 | −0.3690 | 0.035* | |
H3B | 0.4804 | 1.3827 | −0.2801 | 0.035* | |
C4 | 0.2177 (2) | 1.4634 (2) | −0.18521 (19) | 0.0241 (4) | |
H4A | 0.2619 | 1.4621 | −0.1083 | 0.029* | |
H4B | 0.1879 | 1.5777 | −0.2398 | 0.029* | |
C5 | 0.0571 (2) | 1.3689 (2) | −0.1332 (2) | 0.0234 (4) | |
H5A | −0.0213 | 1.3836 | −0.0455 | 0.028* | |
H5B | −0.0151 | 1.4045 | −0.2015 | 0.028* | |
C6 | 0.3039 (3) | 1.2418 (2) | 0.16305 (19) | 0.0255 (4) | |
H6A | 0.1832 | 1.3051 | 0.1644 | 0.031* | |
H6B | 0.3557 | 1.2232 | 0.0728 | 0.031* | |
C7 | 0.4267 (3) | 1.3306 (2) | 0.1891 (2) | 0.0281 (4) | |
H7A | 0.3970 | 1.4502 | 0.1531 | 0.034* | |
H7B | 0.5551 | 1.3005 | 0.1467 | 0.034* | |
C8 | 0.3863 (3) | 1.2716 (2) | 0.3456 (2) | 0.0306 (4) | |
H8A | 0.4889 | 1.2808 | 0.3764 | 0.037* | |
H8B | 0.2762 | 1.3341 | 0.3867 | 0.037* | |
C9 | 0.3588 (3) | 1.0954 (2) | 0.38312 (19) | 0.0246 (4) | |
H9A | 0.4740 | 1.0239 | 0.3878 | 0.030* | |
H9B | 0.2700 | 1.0606 | 0.4734 | 0.030* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn1 | 0.02186 (12) | 0.02004 (11) | 0.01819 (11) | −0.00295 (8) | −0.00913 (8) | −0.00399 (8) |
Cr1 | 0.01368 (17) | 0.01423 (17) | 0.01660 (18) | −0.00112 (13) | −0.00625 (13) | −0.00473 (14) |
Cl1 | 0.01863 (19) | 0.02114 (19) | 0.0218 (2) | 0.00005 (15) | −0.00807 (15) | −0.00949 (15) |
Cl2 | 0.01718 (18) | 0.0235 (2) | 0.0208 (2) | 0.00153 (15) | −0.00830 (15) | −0.00916 (16) |
O2 | 0.0307 (7) | 0.0248 (6) | 0.0221 (6) | −0.0082 (5) | −0.0147 (5) | −0.0039 (5) |
O1 | 0.0160 (6) | 0.0160 (5) | 0.0247 (6) | −0.0005 (4) | −0.0028 (5) | −0.0073 (5) |
C1 | 0.0348 (10) | 0.0267 (9) | 0.0218 (9) | −0.0001 (8) | −0.0082 (8) | −0.0013 (7) |
C2 | 0.0175 (8) | 0.0255 (9) | 0.0379 (11) | −0.0050 (7) | 0.0021 (7) | −0.0153 (8) |
C3 | 0.0270 (9) | 0.0243 (9) | 0.0282 (10) | −0.0037 (7) | −0.0013 (8) | −0.0031 (8) |
C4 | 0.0273 (9) | 0.0166 (8) | 0.0267 (9) | −0.0049 (7) | −0.0075 (7) | −0.0031 (7) |
C5 | 0.0219 (8) | 0.0156 (8) | 0.0310 (9) | 0.0010 (7) | −0.0061 (7) | −0.0079 (7) |
C6 | 0.0274 (9) | 0.0249 (9) | 0.0244 (9) | −0.0056 (7) | −0.0112 (7) | −0.0027 (7) |
C7 | 0.0262 (9) | 0.0273 (9) | 0.0334 (10) | −0.0069 (7) | −0.0085 (8) | −0.0097 (8) |
C8 | 0.0322 (10) | 0.0363 (10) | 0.0329 (10) | −0.0076 (8) | −0.0097 (8) | −0.0188 (9) |
C9 | 0.0254 (9) | 0.0335 (10) | 0.0206 (8) | −0.0029 (7) | −0.0109 (7) | −0.0113 (7) |
Zn1—C1 | 1.9618 (18) | C3—C4 | 1.524 (3) |
Zn1—O2 | 2.0913 (13) | C3—H3A | 0.9900 |
Zn1—Cl1 | 2.3105 (5) | C3—H3B | 0.9900 |
Zn1—Cl2 | 2.3954 (6) | C4—C5 | 1.511 (2) |
Cr1—O1i | 2.0548 (12) | C4—H4A | 0.9900 |
Cr1—O1 | 2.0548 (12) | C4—H4B | 0.9900 |
Cr1—Cl2 | 2.4576 (5) | C5—H5A | 0.9900 |
Cr1—Cl2i | 2.4576 (5) | C5—H5B | 0.9900 |
Cr1—Cl1 | 2.7149 (6) | C6—C7 | 1.514 (3) |
Cr1—Cl1i | 2.7149 (6) | C6—H6A | 0.9900 |
O2—C6 | 1.452 (2) | C6—H6B | 0.9900 |
O2—C9 | 1.455 (2) | C7—C8 | 1.524 (3) |
O1—C5 | 1.4523 (19) | C7—H7A | 0.9900 |
O1—C2 | 1.461 (2) | C7—H7B | 0.9900 |
C1—H1A | 0.9800 | C8—C9 | 1.513 (3) |
C1—H1B | 0.9800 | C8—H8A | 0.9900 |
C1—H1C | 0.9800 | C8—H8B | 0.9900 |
C2—C3 | 1.508 (3) | C9—H9A | 0.9900 |
C2—H2A | 0.9900 | C9—H9B | 0.9900 |
C2—H2B | 0.9900 | ||
C1—Zn1—O2 | 111.80 (7) | C2—C3—H3A | 110.9 |
C1—Zn1—Cl1 | 130.04 (6) | C4—C3—H3A | 110.9 |
O2—Zn1—Cl1 | 97.36 (4) | C2—C3—H3B | 110.9 |
C1—Zn1—Cl2 | 117.76 (6) | C4—C3—H3B | 110.9 |
O2—Zn1—Cl2 | 98.98 (4) | H3A—C3—H3B | 108.9 |
Cl1—Zn1—Cl2 | 95.261 (17) | C5—C4—C3 | 102.30 (14) |
O1i—Cr1—O1 | 180.000 (1) | C5—C4—H4A | 111.3 |
O1i—Cr1—Cl2 | 90.19 (4) | C3—C4—H4A | 111.3 |
O1—Cr1—Cl2 | 89.81 (4) | C5—C4—H4B | 111.3 |
O1i—Cr1—Cl2i | 89.81 (4) | C3—C4—H4B | 111.3 |
O1—Cr1—Cl2i | 90.19 (4) | H4A—C4—H4B | 109.2 |
Cl2—Cr1—Cl2i | 180.0 | O1—C5—C4 | 104.41 (13) |
O1i—Cr1—Cl1 | 88.09 (4) | O1—C5—H5A | 110.9 |
O1—Cr1—Cl1 | 91.91 (4) | C4—C5—H5A | 110.9 |
Cl2—Cr1—Cl1 | 84.326 (15) | O1—C5—H5B | 110.9 |
Cl2i—Cr1—Cl1 | 95.674 (15) | C4—C5—H5B | 110.9 |
O1i—Cr1—Cl1i | 91.91 (4) | H5A—C5—H5B | 108.9 |
O1—Cr1—Cl1i | 88.09 (4) | O2—C6—C7 | 105.12 (14) |
Cl2—Cr1—Cl1i | 95.674 (15) | O2—C6—H6A | 110.7 |
Cl2i—Cr1—Cl1i | 84.326 (15) | C7—C6—H6A | 110.7 |
Cl1—Cr1—Cl1i | 180.0 | O2—C6—H6B | 110.7 |
Zn1—Cl1—Cr1 | 87.281 (16) | C7—C6—H6B | 110.7 |
Zn1—Cl2—Cr1 | 91.639 (17) | H6A—C6—H6B | 108.8 |
C6—O2—C9 | 110.02 (13) | C6—C7—C8 | 102.64 (15) |
C6—O2—Zn1 | 123.52 (10) | C6—C7—H7A | 111.2 |
C9—O2—Zn1 | 123.81 (11) | C8—C7—H7A | 111.2 |
C5—O1—C2 | 109.26 (12) | C6—C7—H7B | 111.2 |
C5—O1—Cr1 | 125.54 (10) | C8—C7—H7B | 111.2 |
C2—O1—Cr1 | 124.56 (10) | H7A—C7—H7B | 109.2 |
Zn1—C1—H1A | 109.5 | C9—C8—C7 | 102.88 (15) |
Zn1—C1—H1B | 109.5 | C9—C8—H8A | 111.2 |
H1A—C1—H1B | 109.5 | C7—C8—H8A | 111.2 |
Zn1—C1—H1C | 109.5 | C9—C8—H8B | 111.2 |
H1A—C1—H1C | 109.5 | C7—C8—H8B | 111.2 |
H1B—C1—H1C | 109.5 | H8A—C8—H8B | 109.1 |
O1—C2—C3 | 106.21 (14) | O2—C9—C8 | 105.60 (14) |
O1—C2—H2A | 110.5 | O2—C9—H9A | 110.6 |
C3—C2—H2A | 110.5 | C8—C9—H9A | 110.6 |
O1—C2—H2B | 110.5 | O2—C9—H9B | 110.6 |
C3—C2—H2B | 110.5 | C8—C9—H9B | 110.6 |
H2A—C2—H2B | 108.7 | H9A—C9—H9B | 108.8 |
C2—C3—C4 | 104.22 (15) | ||
C1—Zn1—Cl1—Cr1 | −124.30 (8) | Cl2i—Cr1—O1—C5 | 39.34 (13) |
O2—Zn1—Cl1—Cr1 | 108.99 (4) | Cl1—Cr1—O1—C5 | −56.34 (13) |
Cl2—Zn1—Cl1—Cr1 | 9.204 (14) | Cl1i—Cr1—O1—C5 | 123.66 (13) |
O1i—Cr1—Cl1—Zn1 | 81.41 (4) | Cl2—Cr1—O1—C2 | 49.54 (13) |
O1—Cr1—Cl1—Zn1 | −98.59 (4) | Cl2i—Cr1—O1—C2 | −130.46 (13) |
Cl2—Cr1—Cl1—Zn1 | −8.975 (14) | Cl1—Cr1—O1—C2 | 133.85 (13) |
Cl2i—Cr1—Cl1—Zn1 | 171.025 (14) | Cl1i—Cr1—O1—C2 | −46.15 (13) |
C1—Zn1—Cl2—Cr1 | 130.96 (7) | C5—O1—C2—C3 | 3.4 (2) |
O2—Zn1—Cl2—Cr1 | −108.50 (4) | Cr1—O1—C2—C3 | 174.67 (12) |
Cl1—Zn1—Cl2—Cr1 | −10.170 (15) | O1—C2—C3—C4 | 19.4 (2) |
O1i—Cr1—Cl2—Zn1 | −79.41 (4) | C2—C3—C4—C5 | −33.82 (19) |
O1—Cr1—Cl2—Zn1 | 100.59 (4) | C2—O1—C5—C4 | −25.10 (18) |
Cl1—Cr1—Cl2—Zn1 | 8.648 (13) | Cr1—O1—C5—C4 | 163.78 (11) |
Cl1i—Cr1—Cl2—Zn1 | −171.352 (13) | C3—C4—C5—O1 | 36.09 (18) |
C1—Zn1—O2—C6 | −174.25 (14) | C9—O2—C6—C7 | 14.67 (19) |
Cl1—Zn1—O2—C6 | −35.63 (13) | Zn1—O2—C6—C7 | 176.82 (11) |
Cl2—Zn1—O2—C6 | 60.92 (13) | O2—C6—C7—C8 | −31.90 (19) |
C1—Zn1—O2—C9 | −14.53 (15) | C6—C7—C8—C9 | 36.79 (19) |
Cl1—Zn1—O2—C9 | 124.09 (13) | C6—O2—C9—C8 | 8.89 (19) |
Cl2—Zn1—O2—C9 | −139.37 (13) | Zn1—O2—C9—C8 | −153.20 (12) |
Cl2—Cr1—O1—C5 | −140.66 (13) | C7—C8—C9—O2 | −28.48 (19) |
Symmetry code: (i) −x, −y+2, −z. |
Experimental details
Crystal data | |
Chemical formula | [CrZn2(CH3)2Cl4(C4H8O)4] |
Mr | 643.02 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 120 |
a, b, c (Å) | 7.8530 (14), 8.8695 (16), 10.7901 (19) |
α, β, γ (°) | 68.759 (2), 71.741 (2), 77.434 (2) |
V (Å3) | 660.6 (2) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 2.63 |
Crystal size (mm) | 0.10 × 0.06 × 0.04 |
Data collection | |
Diffractometer | Bruker APEX diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2003) |
Tmin, Tmax | 0.779, 0.902 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7317, 2938, 2794 |
Rint | 0.016 |
(sin θ/λ)max (Å−1) | 0.664 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.023, 0.059, 1.03 |
No. of reflections | 2938 |
No. of parameters | 134 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.36, −0.22 |
Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Sheldrick, 2001), SHELXTL.
Subscribe to Acta Crystallographica Section C: Structural Chemistry
The full text of this article is available to subscribers to the journal.
- Information on subscribing
- Sample issue
- Purchase subscription
- Reduced-price subscriptions
- If you have already subscribed, you may need to register
We have recently been investigating the organometallic chemistry of chromium supported by a bis-(N-heterocyclic) carbene ligand (L) (Kreisel et al., 2006). In the hope of synthesizing a stable methyl complex of chromium(II), we reacted ZnMe2 with the chromium dichloride precursor LCrCl2(THF), (I) (THF is tetrahydrofuran). However, isolation of the product gave the title complex, (II), as colorless crystals from THF at 263 K in good yield.
Complex (II) is trinuclear, containing an octahedral Cr atom located at an inversion center. The Cr atom is ligated by four bridging, equatorial chloro ligands and two axial THF ligands. Furthermore, each pair of bridging Cl atoms is coordinated to a tetrahedral Zn atom, which has methyl and THF ligands. The complex is a congener of a previously reported vanadium complex, V(THF)2[(µ2-Cl)2ZnCl(PPh3)]2, (III), making it the second known complex with a Zn—(X)2—M—(X)2—Zn motif (Cotton et al., 1985), where M is any metal and X is any halide.
The Cr1—Cl2 bond length in (II) is 2.4576 (5) Å; however, the Cr1—Cl1 bond length is considerably longer at 2.7149 (6) Å. In the vanadium analog, these bond distances are more similar to each other [2.501 (1) and 2.526 (1) Å]. We propose that the significant lengthening of the Cr1—Cl1 bond is caused by a Jahn–Teller distortion, which is due to an unpaired electron that occupies either of the degenerate dz2 or dx2-y2 orbitals of an octahedral complex. Complex (III) does not show this distortion because there are no electrons in these degenerate orbitals. The asymmetry in the bridging chlorine distances to the Zn atoms [2.3105 (5) and 2.3954 (6) Å] may be due to the increased basicity of Cl1, which is involved in the Jahn–Teller distortion. A longer Cr1—Cl1 distance indicates less orbital overlap of the lone pair electrons of the chloro ligand with the Cr atom, suggesting more localization of the electrons in the Zn1—Cl1 bond. In addition, the acute Cl1—Cr1—Cl2 bond angle of 84.33 (2)° reflects the large Cr···Zn interatomic separation of 3.481 (6) Å.
Alternatively, one can think of the asymmetric binding of the bridging Cl atoms as a weak ZnMeCl(THF) adduct of square-planar CrCl2(THF)2. Similar cases of apparent distorted octahedral coordination geometries of high-spin CrII metal centers have been interpreted as square-pyramidal coordination with a weakly coordinated ligand occupying a sixth site (Robertson et al., 2003). In either interpretation of the coordination geometry, the electronic structure should remain the same.