Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270109001851/tr3052sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270109001851/tr3052Isup2.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270109001851/tr3052IIsup3.hkl |
CCDC references: 728200; 728201
Through a solution of (η5-carboxycyclopentadienyl)dicarbonylnitrosylchromium (cynichrodenoic acid), (5) (2.49 g, 9.56 mmol), in 30 ml of 2-propanol, hydrogen bromide was bubbled for 5 min. After cooling to 273–283 K with stirring for 20 min (an orange–red solution resulted), isoamyl nitrite (2.6 ml, 19.12 mmol) was added slowly. Carbon oxide evolved and the solution subsequently changed to dark green. The reaction mixture was stirred continuously for 1 h. After concentration of the solution to 10 ml, dichloromethane (30 ml) was added and a large quantity of dark-green solid precipitated out. The solid was obtained through frit filtration and washed several times with distilled water. Compound (I) (yield 2.24 g, 74%) was obtained after vacuum drying (Wang et al., 2007). An X-ray sample (granular black–brown crystals) was prepared by recrystallization using the solvent expansion method from hexane–tetrahydrofuran (5:2) at 273 K for 48 h. The same procedure was followed for the preparation of compound (II) (in 90% yield), starting from (η5–benzoylcyclopentadienyl)dicarbonylnitrosylchromium (benzoylcynichrodene), (6) (1.23 g, 4.00 mmol).
The O3 hydroxy H atom in (I) was refined. All other H atoms in (I) and (II) were placed in geometrically calculated positions, with Uiso(H) values of 1.2Ueq(parent atom). The hydroxyl H atom in (I) was refined.
For both compounds, data collection: CAD-4 (Enraf–Nonius, 1994). Cell refinement: CAD-4 (Enraf–Nonius, 1994 for (I); CAD-4 (Enraf–Nonius, 1994) for (II). For both compounds, data reduction: NRCVAX DATRD2 (Gabe et al., 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Version 6.10; Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Version 6.10; Sheldrick, 2008).
[CrBr(C6H5O2)(NO)2] | F(000) = 584 |
Mr = 301.03 | Dx = 2.115 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 25 reflections |
a = 7.6395 (19) Å | θ = 7.9–14.0° |
b = 10.591 (2) Å | µ = 5.42 mm−1 |
c = 12.122 (2) Å | T = 293 K |
β = 105.40 (2)° | Block, dark brown |
V = 945.6 (4) Å3 | 0.50 × 0.40 × 0.30 mm |
Z = 4 |
Enraf–Nonius CAD-4 diffractometer | 1408 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.040 |
Graphite monochromator | θmax = 27.5°, θmin = 2.6° |
ω–2θ scans, 0.80+0.35tanθ | h = −9→9 |
Absorption correction: ψ scan (North et al., 1968) | k = 0→13 |
Tmin = 0.141, Tmax = 0.236 | l = 0→15 |
2378 measured reflections | 3 standard reflections every 60 min |
2168 independent reflections | intensity decay: none |
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)] = 0.033 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.100 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.99 | w = 1/[σ2(Fo2) + (0.0575P)2] where P = (Fo2 + 2Fc2)/3 |
2168 reflections | (Δ/σ)max = 0.005 |
131 parameters | Δρmax = 0.51 e Å−3 |
0 restraints | Δρmin = −0.61 e Å−3 |
[CrBr(C6H5O2)(NO)2] | V = 945.6 (4) Å3 |
Mr = 301.03 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 7.6395 (19) Å | µ = 5.42 mm−1 |
b = 10.591 (2) Å | T = 293 K |
c = 12.122 (2) Å | 0.50 × 0.40 × 0.30 mm |
β = 105.40 (2)° |
Enraf–Nonius CAD-4 diffractometer | 1408 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.040 |
Tmin = 0.141, Tmax = 0.236 | 3 standard reflections every 60 min |
2378 measured reflections | intensity decay: none |
2168 independent reflections |
R[F2 > 2σ(F2)] = 0.033 | 0 restraints |
wR(F2) = 0.100 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.99 | Δρmax = 0.51 e Å−3 |
2168 reflections | Δρmin = −0.61 e Å−3 |
131 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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. |
x | y | z | Uiso*/Ueq | ||
Cr1 | 0.36595 (7) | 0.10857 (6) | 0.24597 (5) | 0.03117 (17) | |
Br1 | 0.36451 (7) | 0.30386 (5) | 0.35484 (4) | 0.05872 (19) | |
N1 | 0.5041 (5) | 0.0169 (4) | 0.3494 (3) | 0.0442 (8) | |
N2 | 0.5362 (4) | 0.1432 (3) | 0.1840 (3) | 0.0387 (7) | |
C1 | 0.0958 (5) | 0.0356 (4) | 0.2461 (3) | 0.0333 (8) | |
C2 | 0.1862 (5) | −0.0532 (4) | 0.1919 (4) | 0.0385 (9) | |
H2 | 0.2198 | −0.1348 | 0.2172 | 0.046* | |
C3 | 0.2157 (5) | 0.0033 (4) | 0.0949 (3) | 0.0426 (10) | |
H3 | 0.2732 | −0.0338 | 0.0443 | 0.051* | |
C4 | 0.1426 (5) | 0.1275 (4) | 0.0863 (3) | 0.0411 (9) | |
H4 | 0.1448 | 0.1862 | 0.0297 | 0.049* | |
C5 | 0.0674 (5) | 0.1452 (4) | 0.1777 (3) | 0.0380 (9) | |
H5 | 0.0079 | 0.2177 | 0.1916 | 0.046* | |
C6 | 0.0472 (5) | 0.0184 (4) | 0.3540 (3) | 0.0356 (8) | |
O1 | 0.5907 (5) | −0.0574 (4) | 0.4102 (3) | 0.0686 (10) | |
O2 | 0.6457 (4) | 0.1541 (4) | 0.1345 (3) | 0.0630 (9) | |
O3 | −0.0410 (4) | 0.1076 (3) | 0.3847 (3) | 0.0503 (8) | |
O4 | 0.0956 (4) | −0.0810 (2) | 0.4107 (2) | 0.0460 (7) | |
H | −0.040 (7) | 0.102 (5) | 0.447 (5) | 0.064 (17)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cr1 | 0.0294 (3) | 0.0384 (3) | 0.0281 (3) | −0.0041 (3) | 0.0119 (2) | −0.0022 (3) |
Br1 | 0.0763 (4) | 0.0523 (3) | 0.0580 (3) | −0.0210 (2) | 0.0360 (3) | −0.0228 (2) |
N1 | 0.0411 (19) | 0.057 (2) | 0.0355 (18) | −0.0024 (17) | 0.0118 (15) | −0.0019 (17) |
N2 | 0.0329 (17) | 0.052 (2) | 0.0338 (17) | −0.0073 (15) | 0.0125 (14) | −0.0020 (15) |
C1 | 0.0304 (19) | 0.040 (2) | 0.0317 (19) | −0.0034 (15) | 0.0117 (16) | −0.0002 (16) |
C2 | 0.039 (2) | 0.036 (2) | 0.043 (2) | −0.0028 (17) | 0.0144 (18) | −0.0078 (18) |
C3 | 0.037 (2) | 0.060 (3) | 0.031 (2) | −0.0054 (19) | 0.0093 (16) | −0.009 (2) |
C4 | 0.037 (2) | 0.055 (3) | 0.032 (2) | −0.0032 (19) | 0.0087 (16) | 0.0071 (19) |
C5 | 0.0297 (18) | 0.043 (2) | 0.043 (2) | 0.0010 (16) | 0.0123 (16) | 0.0036 (18) |
C6 | 0.036 (2) | 0.037 (2) | 0.039 (2) | −0.0089 (16) | 0.0192 (17) | −0.0030 (17) |
O1 | 0.071 (2) | 0.080 (2) | 0.048 (2) | 0.016 (2) | 0.0035 (18) | 0.0163 (19) |
O2 | 0.0448 (18) | 0.096 (3) | 0.058 (2) | −0.0099 (17) | 0.0314 (16) | −0.0007 (19) |
O3 | 0.062 (2) | 0.0496 (18) | 0.053 (2) | 0.0112 (15) | 0.0396 (17) | 0.0054 (16) |
O4 | 0.0644 (19) | 0.0339 (15) | 0.0443 (17) | −0.0023 (13) | 0.0221 (15) | 0.0041 (13) |
Cr1—N2 | 1.706 (3) | C1—C6 | 1.462 (5) |
Cr1—N1 | 1.710 (4) | C2—C3 | 1.390 (6) |
Cr1—C2 | 2.184 (4) | C2—H2 | 0.9300 |
Cr1—C3 | 2.191 (4) | C3—C4 | 1.422 (6) |
Cr1—C1 | 2.204 (4) | C3—H3 | 0.9300 |
Cr1—C4 | 2.223 (4) | C4—C5 | 1.390 (6) |
Cr1—C5 | 2.244 (4) | C4—H4 | 0.9300 |
Cr1—Br1 | 2.4551 (8) | C5—H5 | 0.9300 |
N1—O1 | 1.158 (4) | C6—O4 | 1.258 (5) |
N2—O2 | 1.158 (4) | C6—O3 | 1.272 (5) |
C1—C5 | 1.409 (5) | O3—H | 0.75 (5) |
C1—C2 | 1.426 (5) | ||
N2—Cr1—N1 | 92.92 (16) | C2—C1—C6 | 126.8 (4) |
N2—Cr1—C2 | 121.91 (16) | C5—C1—Cr1 | 73.1 (2) |
N1—Cr1—C2 | 89.49 (17) | C2—C1—Cr1 | 70.3 (2) |
N2—Cr1—C3 | 91.87 (16) | C6—C1—Cr1 | 120.3 (3) |
N1—Cr1—C3 | 114.10 (17) | C3—C2—C1 | 108.2 (4) |
C2—Cr1—C3 | 37.06 (15) | C3—C2—Cr1 | 71.7 (2) |
N2—Cr1—C1 | 154.07 (15) | C1—C2—Cr1 | 71.8 (2) |
N1—Cr1—C1 | 101.30 (15) | C3—C2—H2 | 125.9 |
C2—Cr1—C1 | 37.93 (14) | C1—C2—H2 | 125.9 |
C3—Cr1—C1 | 62.57 (15) | Cr1—C2—H2 | 122.3 |
N2—Cr1—C4 | 95.48 (15) | C2—C3—C4 | 108.1 (4) |
N1—Cr1—C4 | 150.54 (17) | C2—C3—Cr1 | 71.2 (2) |
C2—Cr1—C4 | 62.20 (16) | C4—C3—Cr1 | 72.5 (2) |
C3—Cr1—C4 | 37.57 (15) | C2—C3—H3 | 125.9 |
C1—Cr1—C4 | 61.97 (14) | C4—C3—H3 | 125.9 |
N2—Cr1—C5 | 128.29 (16) | Cr1—C3—H3 | 122.1 |
N1—Cr1—C5 | 137.50 (15) | C5—C4—C3 | 107.7 (4) |
C2—Cr1—C5 | 61.88 (15) | C5—C4—Cr1 | 72.7 (2) |
C3—Cr1—C5 | 61.59 (15) | C3—C4—Cr1 | 70.0 (2) |
C1—Cr1—C5 | 36.93 (14) | C5—C4—H4 | 126.2 |
C4—Cr1—C5 | 36.26 (14) | C3—C4—H4 | 126.2 |
N2—Cr1—Br1 | 99.69 (12) | Cr1—C4—H4 | 122.9 |
N1—Cr1—Br1 | 100.03 (12) | C4—C5—C1 | 109.0 (4) |
C2—Cr1—Br1 | 136.87 (10) | C4—C5—Cr1 | 71.1 (2) |
C3—Cr1—Br1 | 143.33 (12) | C1—C5—Cr1 | 70.0 (2) |
C1—Cr1—Br1 | 99.04 (10) | C4—C5—H5 | 125.5 |
C4—Cr1—Br1 | 106.27 (12) | C1—C5—H5 | 125.5 |
C5—Cr1—Br1 | 84.45 (11) | Cr1—C5—H5 | 125.0 |
O1—N1—Cr1 | 171.6 (3) | O4—C6—O3 | 124.2 (4) |
O2—N2—Cr1 | 172.0 (3) | O4—C6—C1 | 119.1 (3) |
C5—C1—C2 | 106.9 (3) | O3—C6—C1 | 116.7 (4) |
C5—C1—C6 | 126.3 (3) | C6—O3—H | 112 (4) |
[CrBr(C12H9O)(NO)2] | F(000) = 712 |
Mr = 361.12 | Dx = 1.865 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 25 reflections |
a = 12.1936 (13) Å | θ = 8.9–15.2° |
b = 6.5027 (9) Å | µ = 4.00 mm−1 |
c = 16.305 (2) Å | T = 293 K |
β = 95.731 (10)° | Block, brown |
V = 1286.4 (3) Å3 | 0.55 × 0.45 × 0.30 mm |
Z = 4 |
Enraf–Nonius CAD-4 diffractometer | 1881 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.040 |
Graphite monochromator | θmax = 27.5°, θmin = 1.7° |
ω–2θ scans | h = −15→15 |
Absorption correction: ψ scan North et al., 1968 | k = 0→8 |
Tmin = 0.220, Tmax = 0.333 | l = 0→21 |
3233 measured reflections | 3 standard reflections every 60 min |
2952 independent reflections | intensity decay: none |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.037 | H-atom parameters constrained |
wR(F2) = 0.130 | w = 1/[σ2(Fo2) + (0.0713P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max = 0.001 |
2952 reflections | Δρmax = 0.40 e Å−3 |
173 parameters | Δρmin = −0.61 e Å−3 |
0 restraints | Extinction correction: SHELXL97, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0043 (9) |
[CrBr(C12H9O)(NO)2] | V = 1286.4 (3) Å3 |
Mr = 361.12 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 12.1936 (13) Å | µ = 4.00 mm−1 |
b = 6.5027 (9) Å | T = 293 K |
c = 16.305 (2) Å | 0.55 × 0.45 × 0.30 mm |
β = 95.731 (10)° |
Enraf–Nonius CAD-4 diffractometer | 1881 reflections with I > 2σ(I) |
Absorption correction: ψ scan North et al., 1968 | Rint = 0.040 |
Tmin = 0.220, Tmax = 0.333 | 3 standard reflections every 60 min |
3233 measured reflections | intensity decay: none |
2952 independent reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.130 | H-atom parameters constrained |
S = 1.09 | Δρmax = 0.40 e Å−3 |
2952 reflections | Δρmin = −0.61 e Å−3 |
173 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Cr1 | 0.14034 (5) | 0.13650 (9) | 0.88831 (3) | 0.03404 (19) | |
Br1 | 0.10425 (4) | −0.22495 (8) | 0.85592 (3) | 0.0651 (2) | |
N1 | 0.1574 (3) | 0.2166 (6) | 0.7898 (2) | 0.0441 (8) | |
N2 | 0.0073 (3) | 0.2220 (6) | 0.8815 (2) | 0.0467 (8) | |
C1 | 0.3137 (3) | 0.1278 (6) | 0.9477 (2) | 0.0356 (8) | |
C2 | 0.2466 (3) | 0.0263 (7) | 1.0000 (2) | 0.0435 (9) | |
H2 | 0.2533 | −0.1111 | 1.0155 | 0.052* | |
C3 | 0.1689 (4) | 0.1623 (8) | 1.0251 (2) | 0.0483 (10) | |
H3 | 0.1154 | 0.1326 | 1.0602 | 0.058* | |
C4 | 0.1855 (3) | 0.3526 (7) | 0.9880 (3) | 0.0480 (10) | |
H4 | 0.1440 | 0.4708 | 0.9936 | 0.058* | |
C5 | 0.2742 (3) | 0.3348 (6) | 0.9413 (2) | 0.0394 (9) | |
H5 | 0.3030 | 0.4396 | 0.9110 | 0.047* | |
C6 | 0.4058 (3) | 0.0223 (6) | 0.9113 (2) | 0.0386 (9) | |
C7 | 0.4939 (3) | 0.1441 (6) | 0.8757 (2) | 0.0365 (8) | |
C8 | 0.5205 (3) | 0.3432 (7) | 0.8990 (2) | 0.0437 (9) | |
H8 | 0.4802 | 0.4100 | 0.9366 | 0.052* | |
C9 | 0.6070 (3) | 0.4453 (8) | 0.8671 (3) | 0.0551 (12) | |
H9 | 0.6247 | 0.5794 | 0.8832 | 0.066* | |
C10 | 0.6666 (3) | 0.3453 (9) | 0.8110 (3) | 0.0615 (14) | |
H10 | 0.7245 | 0.4125 | 0.7894 | 0.074* | |
C11 | 0.6405 (4) | 0.1489 (9) | 0.7873 (3) | 0.0590 (13) | |
H11 | 0.6805 | 0.0836 | 0.7492 | 0.071* | |
C12 | 0.5545 (3) | 0.0444 (7) | 0.8196 (2) | 0.0457 (10) | |
H12 | 0.5378 | −0.0904 | 0.8038 | 0.055* | |
O1 | 0.1722 (3) | 0.2894 (7) | 0.7282 (2) | 0.0768 (11) | |
O2 | −0.0771 (3) | 0.3023 (7) | 0.8817 (3) | 0.0809 (11) | |
O3 | 0.4117 (2) | −0.1651 (5) | 0.9143 (2) | 0.0535 (8) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cr1 | 0.0331 (3) | 0.0359 (3) | 0.0335 (3) | 0.0035 (2) | 0.0050 (2) | 0.0024 (3) |
Br1 | 0.0687 (4) | 0.0445 (3) | 0.0807 (4) | −0.0027 (2) | −0.0003 (3) | −0.0023 (2) |
N1 | 0.0452 (18) | 0.049 (2) | 0.0368 (18) | −0.0013 (16) | −0.0002 (14) | 0.0028 (16) |
N2 | 0.0375 (18) | 0.053 (2) | 0.050 (2) | 0.0047 (16) | 0.0044 (15) | −0.0017 (17) |
C1 | 0.0368 (19) | 0.037 (2) | 0.0324 (18) | 0.0001 (16) | 0.0000 (14) | 0.0030 (16) |
C2 | 0.047 (2) | 0.051 (3) | 0.0325 (19) | 0.0013 (19) | 0.0034 (16) | 0.0105 (18) |
C3 | 0.048 (2) | 0.068 (3) | 0.0301 (19) | 0.000 (2) | 0.0110 (16) | 0.002 (2) |
C4 | 0.047 (2) | 0.053 (3) | 0.044 (2) | 0.006 (2) | 0.0054 (18) | −0.016 (2) |
C5 | 0.040 (2) | 0.038 (2) | 0.040 (2) | 0.0006 (17) | 0.0014 (16) | 0.0002 (17) |
C6 | 0.0353 (19) | 0.043 (2) | 0.0368 (19) | 0.0031 (17) | −0.0024 (15) | 0.0012 (17) |
C7 | 0.0325 (17) | 0.044 (2) | 0.0315 (18) | 0.0056 (16) | −0.0025 (14) | 0.0039 (16) |
C8 | 0.040 (2) | 0.050 (2) | 0.040 (2) | −0.0024 (18) | −0.0004 (16) | −0.0067 (19) |
C9 | 0.048 (2) | 0.057 (3) | 0.056 (3) | −0.008 (2) | −0.012 (2) | 0.008 (2) |
C10 | 0.033 (2) | 0.085 (4) | 0.065 (3) | −0.002 (2) | 0.002 (2) | 0.027 (3) |
C11 | 0.044 (2) | 0.082 (4) | 0.053 (3) | 0.018 (2) | 0.017 (2) | 0.010 (3) |
C12 | 0.040 (2) | 0.051 (3) | 0.045 (2) | 0.0120 (18) | 0.0034 (17) | −0.0008 (19) |
O1 | 0.085 (3) | 0.105 (3) | 0.0401 (18) | −0.020 (2) | 0.0055 (17) | 0.0258 (19) |
O2 | 0.0461 (19) | 0.103 (3) | 0.094 (3) | 0.028 (2) | 0.0103 (18) | −0.006 (2) |
O3 | 0.0556 (18) | 0.0384 (17) | 0.068 (2) | 0.0101 (14) | 0.0114 (15) | 0.0061 (15) |
Cr1—N2 | 1.708 (3) | C4—C5 | 1.389 (5) |
Cr1—N1 | 1.721 (3) | C4—H4 | 0.9300 |
Cr1—C4 | 2.177 (4) | C5—H5 | 0.9300 |
Cr1—C5 | 2.189 (4) | C6—O3 | 1.221 (5) |
Cr1—C3 | 2.229 (4) | C6—C7 | 1.497 (5) |
Cr1—C1 | 2.236 (4) | C7—C8 | 1.380 (6) |
Cr1—C2 | 2.245 (4) | C7—C12 | 1.392 (5) |
Cr1—Br1 | 2.4394 (8) | C8—C9 | 1.391 (6) |
N1—O1 | 1.140 (4) | C8—H8 | 0.9300 |
N2—O2 | 1.154 (4) | C9—C10 | 1.385 (7) |
C1—C2 | 1.405 (5) | C9—H9 | 0.9300 |
C1—C5 | 1.430 (6) | C10—C11 | 1.363 (8) |
C1—C6 | 1.489 (5) | C10—H10 | 0.9300 |
C2—C3 | 1.388 (6) | C11—C12 | 1.396 (6) |
C2—H2 | 0.9300 | C11—H11 | 0.9300 |
C3—C4 | 1.401 (7) | C12—H12 | 0.9300 |
C3—H3 | 0.9300 | ||
N2—Cr1—N1 | 92.50 (17) | Cr1—C2—H2 | 123.7 |
N2—Cr1—C4 | 90.33 (16) | C2—C3—C4 | 107.6 (4) |
N1—Cr1—C4 | 117.15 (17) | C2—C3—Cr1 | 72.5 (2) |
N2—Cr1—C5 | 119.98 (16) | C4—C3—Cr1 | 69.4 (2) |
N1—Cr1—C5 | 92.00 (16) | C2—C3—H3 | 126.2 |
C4—Cr1—C5 | 37.09 (15) | C4—C3—H3 | 126.2 |
N2—Cr1—C3 | 95.31 (17) | Cr1—C3—H3 | 123.5 |
N1—Cr1—C3 | 152.85 (18) | C5—C4—C3 | 108.5 (4) |
C4—Cr1—C3 | 37.06 (18) | C5—C4—Cr1 | 71.9 (2) |
C5—Cr1—C3 | 61.66 (16) | C3—C4—Cr1 | 73.5 (3) |
N2—Cr1—C1 | 152.50 (16) | C5—C4—H4 | 125.7 |
N1—Cr1—C1 | 102.37 (15) | C3—C4—H4 | 125.7 |
C4—Cr1—C1 | 62.33 (15) | Cr1—C4—H4 | 120.6 |
C5—Cr1—C1 | 37.69 (15) | C4—C5—C1 | 108.3 (4) |
C3—Cr1—C1 | 61.49 (14) | C4—C5—Cr1 | 71.0 (2) |
N2—Cr1—C2 | 128.62 (16) | C1—C5—Cr1 | 72.9 (2) |
N1—Cr1—C2 | 137.74 (16) | C4—C5—H5 | 125.9 |
C4—Cr1—C2 | 61.18 (16) | C1—C5—H5 | 125.9 |
C5—Cr1—C2 | 61.36 (15) | Cr1—C5—H5 | 121.9 |
C3—Cr1—C2 | 36.14 (16) | O3—C6—C1 | 119.2 (4) |
C1—Cr1—C2 | 36.55 (14) | O3—C6—C7 | 120.1 (4) |
N2—Cr1—Br1 | 98.63 (13) | C1—C6—C7 | 120.6 (3) |
N1—Cr1—Br1 | 97.21 (12) | C8—C7—C12 | 119.5 (4) |
C4—Cr1—Br1 | 144.12 (13) | C8—C7—C6 | 123.2 (4) |
C5—Cr1—Br1 | 139.85 (11) | C12—C7—C6 | 117.2 (4) |
C3—Cr1—Br1 | 107.22 (13) | C7—C8—C9 | 120.8 (4) |
C1—Cr1—Br1 | 102.23 (10) | C7—C8—H8 | 119.6 |
C2—Cr1—Br1 | 86.86 (12) | C9—C8—H8 | 119.6 |
O1—N1—Cr1 | 172.6 (4) | C10—C9—C8 | 119.4 (5) |
O2—N2—Cr1 | 171.3 (4) | C10—C9—H9 | 120.3 |
C2—C1—C5 | 105.9 (3) | C8—C9—H9 | 120.3 |
C2—C1—C6 | 122.2 (4) | C11—C10—C9 | 120.3 (4) |
C5—C1—C6 | 131.8 (4) | C11—C10—H10 | 119.9 |
C2—C1—Cr1 | 72.1 (2) | C9—C10—H10 | 119.9 |
C5—C1—Cr1 | 69.4 (2) | C10—C11—C12 | 120.8 (4) |
C6—C1—Cr1 | 123.9 (2) | C10—C11—H11 | 119.6 |
C3—C2—C1 | 109.6 (4) | C12—C11—H11 | 119.6 |
C3—C2—Cr1 | 71.3 (2) | C7—C12—C11 | 119.3 (4) |
C1—C2—Cr1 | 71.4 (2) | C7—C12—H12 | 120.4 |
C3—C2—H2 | 125.2 | C11—C12—H12 | 120.4 |
C1—C2—H2 | 125.2 |
Experimental details
(I) | (II) | |
Crystal data | ||
Chemical formula | [CrBr(C6H5O2)(NO)2] | [CrBr(C12H9O)(NO)2] |
Mr | 301.03 | 361.12 |
Crystal system, space group | Monoclinic, P21/c | Monoclinic, P21/c |
Temperature (K) | 293 | 293 |
a, b, c (Å) | 7.6395 (19), 10.591 (2), 12.122 (2) | 12.1936 (13), 6.5027 (9), 16.305 (2) |
β (°) | 105.40 (2) | 95.731 (10) |
V (Å3) | 945.6 (4) | 1286.4 (3) |
Z | 4 | 4 |
Radiation type | Mo Kα | Mo Kα |
µ (mm−1) | 5.42 | 4.00 |
Crystal size (mm) | 0.50 × 0.40 × 0.30 | 0.55 × 0.45 × 0.30 |
Data collection | ||
Diffractometer | Enraf–Nonius CAD-4 diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | ψ scan (North et al., 1968) | ψ scan North et al., 1968 |
Tmin, Tmax | 0.141, 0.236 | 0.220, 0.333 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2378, 2168, 1408 | 3233, 2952, 1881 |
Rint | 0.040 | 0.040 |
(sin θ/λ)max (Å−1) | 0.650 | 0.650 |
Refinement | ||
R[F2 > 2σ(F2)], wR(F2), S | 0.033, 0.100, 0.99 | 0.037, 0.130, 1.09 |
No. of reflections | 2168 | 2952 |
No. of parameters | 131 | 173 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.51, −0.61 | 0.40, −0.61 |
Computer programs: CAD-4 (Enraf–Nonius, 1994), CAD-4 (Enraf–Nonius, 1994, NRCVAX DATRD2 (Gabe et al., 1989), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Version 6.10; Sheldrick, 2008).
Cr1—N1 | 1.710 (4) | C1—C2 | 1.426 (5) |
Cr1—N2 | 1.706 (3) | C1—C6 | 1.462 (5) |
Cr1—Br1 | 2.4551 (8) | C2—C3 | 1.390 (6) |
C6—O4 | 1.258 (5) | C3—C4 | 1.422 (6) |
C6—O3 | 1.272 (5) | C4—C5 | 1.390 (6) |
Cr1···C6 | 3.201 (5) | N1—O1 | 1.158 (4) |
Cr1···Cp | 1.856 | N2—O2 | 1.158 (4) |
O1···Br1 | 4.177 (6) | C1—C5 | 1.409 (5) |
O2···Br1 | 4.161 (5) | ||
N1—Cr1—N2 | 92.92 (16) | C1—C5—Cr1 | 70.0 (2) |
N1—Cr1—Br1 | 100.03 (12) | O4—C6—O3 | 124.2 (4) |
N2—Cr1—Br1 | 99.69 (12) | O4—C6—C1 | 119.1 (3) |
O1—N1—Cr1 | 171.6 (3) | O3—C6—C1 | 116.7 (4) |
O2—N2—Cr1 | 172.0 (3) | Cp—Cr1—N1 | 121.8 |
C5—C1—C6 | 126.3 (4) | Cp—Cr1—N2 | 121.2 |
C2—C1—C6 | 126.8 (4) | Cp—Cr1—Br1 | 116.2 |
C6—C1—Cr1 | 120.3 (3) | ||
Dihedral angles between planes | |||
Cp and carbonyl plane C1/C6/O3/O4 | 5.6 (8) | ||
Cr1/Cp/N1 and Cr1/Cp/C1 | 58.0 (6) | ||
Cr1/Cp/N2 and Cr1/Cp/C1 | 174.5 (3) | ||
Cr1/Cp/Br1 and Cr1/Cp/C1 | 64.2 (7) |
Cr1—N1 | 1.721 (3) | C3—C4 | 1.401 (7) |
Cr1—N2 | 1.708 (3) | C4—C5 | 1.389 (5) |
Cr1—Br1 | 2.4394 (8) | C6—O3 | 1.221 (5) |
Cr1—C1 | 2.236 (4) | C6—C7 | 1.497 (5) |
N1—O1 | 1.140 (4) | N2—O2 | 1.154 (4) |
C1—C2 | 1.405 (5) | Cr1···C6 | 3.306 (1) |
C1—C5 | 1.430 (6) | Cr1···Cp | 1.867 |
C1—C6 | 1.489 (5) | O1···Br1 | 4.068 (7) |
C2—C3 | 1.388 (6) | O2···Br1 | 4.124 (6) |
N1—Cr1—N2 | 92.50 (17) | O3—C6—C7 | 120.1 (4) |
N1—Cr1—Br1 | 97.21 (12) | C1—C6—C7 | 120.6 (3) |
N2—Cr1—Br1 | 98.63 (13) | C6—C7—C8 | 123.2 (4) |
O1—N1—Cr1 | 172.6 (4) | C6—C7—C12 | 117.2 (4) |
O2—N2—Cr1 | 171.3 (4) | Cp—Cr1—N1 | 123.8 |
C2—C1—C6 | 122.2 (4) | Cp—Cr1—N2 | 120.2 |
C5—C1—C6 | 131.8 (4) | Cp—Cr1—Br1 | 118.4 |
O3—C6—C1 | 119.2 (4) | ||
Dihedral angles between planes | |||
Cp and carbonyl plane C1/C6/O3/C7 | 15.2 (3) | ||
Benzene and carbonyl plane C1/C6/O3/C7 | 24.5 (1) | ||
Cp and benzene | 35.3 (1) | ||
Cr1/Cp/N1 and Cr1/Cp/C1 | 55.7 (1) | ||
Cr1/Cp/N2 and Cr1/Cp/C1 | 172.5 (1) | ||
Cr1/Cp/Br1 and Cr1/Cp/C1 | 66.5 (9) |
Although CpCr(NO)2(Br) was first reported in 1956 (Piper & Wilkinson, 1956), the difficulties encountered in making it undergo electrophilic aromatic substitution reactions such as Friedel–Crafts acylation have blocked the way to the synthesis of its Cp derivatives (Rausch et al., 1980). A novel method of replacing two carbonyl groups with a nitrosyl and a chloro ligand using hydrogen chloride/isoamylnitrite has been reported by Wang & Hwu (1990) to convert (1) to (2) (see the first scheme below). The analogous bromide compounds [η5–(C5H4–COOH]Cr(NO)2Br, (I), and [η5–(C5H4–COC6H5)]Cr(NO)2Br, (II), were prepared with the use of hydrogen bromide/isoamylnitrite from (5) and (6), respectively (Wang et al., 2007).
Wang et al. (1995, 1999) reported the qualitative relationship of the nonplanarity of the Cp–exocyclic carbon to the substituent π-donor and π-acceptor interactions. The π-donor substituents and the ipso-C atoms to which they are attached are bent away from the Cr(CO)2NO fragments, while the π-acceptor substituents and the ipso-C atoms to which they are attached lie approximately in the Cp plane or are bent slightly toward the Cr(CO)2NO fragments. The magnitudes and directions of these distortions from planarity with the Cp ring appear to be due primarily to electronic effects. In the hope of confirming these hypotheses, compounds (I) and (II) were studied. The molecular structures of (I) and (II) are shown in Figs. 1 and 2, respectively. Selected bond distances and angles are given in Tables 1 and 2.
The coordination geometry about the Cr center in each case is approximately a distorted tetrahedron with two nitrosyl groups, the Cp group and a Br atom as the four coordination sites. It is worth pointing out that for both structures one of the nitrosyl groups is located at a site away from the exocyclic C atom, i.e. the Br group is located at a site close to the exocyclic C atom.
The twist angle, defined as the torsion angle between the nitrosyl atom N2, the Cr atom, the Cp center and the ring C atom bearing the exocyclic C atom, is 174.5 (3)° for (I) and 172.5 (1)° for (II). The preference for isomer i (see the scheme below) over the symmetrical isomer ii may be related to the ability of the exocyclic double bond to donate electron density to the Cr atom if it is in a position trans to the better π-accepting ligand, i.e. NO+. As a result, the exocyclic C6 atoms of (I) and (II) are bent towards the Cr atom, with θ angles of 2.8 (3) and 0.1 (1)°, respectively. The θ angle is defined as the angle between the exocyclic C—C bond (C1—C6) and the corresponding Cp ring, with a positive angle toward the metal and a negative angle away from the metal.
The fact that the electron-withdrawing carbonyl group on the Cp ring orients itself trans to the stronger electron-withdrawing NO rather than a weaker electron-withdrawing ligand is startling (Rogers et al., 1988). It is interesting to discover that the contribution of the canonical form i to (I) or (II) to some extent was revealed by the carbon–carbon bond lengths in the cyclopentadienyl ring. Comparatively, shorter bond lengths for C2—C3 and C4—C5, and longer bond lengths for C1—C2, C3—C4 and C1—C5, are observed in both (I) and (II).
In view of the shortness of the Cr—N(nitrosyl) distances in (I) and (II) (ca 1.71 Å) compared with the Cr—N(isothiocyanate) distance of 1.983 (3) Å in compound (7) (Wang et al., 2007), appreciable dπ back-donation from the Cr atom to the π* orbitals of the nitrosyl group is demonstrated. It appears that the canonical form iv rather than iii makes a greater contribution to the chromium–nitrosyl bonding. The lesser contribution of v with respect that of iv is reflected by the Cr—N—O angles of ca 171°. These values are similar to those found in (8) [171.2 (5) and 172.1 (4)°] and (9) [176.0 (5) and 174.3 (4)°] (Wang et al., 1991).
The two Cr–centroid [Cp(Cr)] distances agree with the values of 1.844 Å in (1) and 1.884 Å in (η5–C13H9)Cr(CO)2(NO) (Atwood et al., 1979). The average Cr—C(ring) distances of 2.209 (4) and 2.215 (4) Å are close to the value in (2) (2.20 Å). The average C—C distance in the ring [Cp(Cr)] is 1.409 (6) and 1.403 (6)Å for compound (I) and (II), respectively. In the case of (I), the exocyclic C1—C6 bond is considerably shorter than those found in [η5–(1–vinylferrocenyl)methylcyclopentadienyl]dicarbonylnitrosylchromium [1.507 (6) Å; Wang et al., 1989] and (1–cynichrodenoylferrocenyl)cynichrodenylmethane [1.512 (8) Å; Wang et al.,1990], but is comparable to that found in (12) [1.470 (8) Å; Rogers et al., 1988]. Again, the contribution of canonical form i to compound (I) may account for the difference.
It is interesting to note the difference between the structures of (I) and (II). The resonance between the carbonyl and phenyl ring diminishes the extent of the contribution of i to (II). This entails the longer exocyclic C—C bond, a smaller θ [0.1 (1) versus 2.8 (3)°], and a larger dihedral angle between the carbonyl plane and the corresponding Cp(Cr) plane. The results indicate that the resonance between the carbonyl and phenyl group overwhelms the resonance between the carbonyl and Cp(Cr) group. It is conceivable that the two electron-withdrawing nitrosyl groups and the bromide ion on Cr atom deplete the electron density on the Cp(Cr) ring. The π electrons on the Cp(Cr) ring are less available to resonate with the C≡O group. In the case of (II), the carbonyl plane (C1/C6/O3/C7) is turned away from the Cp(Cr) and phenyl rings by 15.2 (3) and 24.5 (1)°, respectively. This rotation might be the result of intramolecular steric interference between atoms H5 and H8. This is supported by the enlargement of bond angles C5—C1—C6 and C8—C7—C6 to 131.8 (4) and 123.2 (4)°, respectively. As a result of the steric interference, the dihedral angle between the Cp(Cr) and benzene rings is quite large [35.3 (1)°].