Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270104031695/sk1790sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270104031695/sk1790Isup2.hkl |
CCDC reference: 264790
Ti(NMe2)3Cl (0.5 g; 2,3 mmol) was dissolved in toluene (30 ml) and HDMP (2.5 mmol) was added slowly. The mixture was refluxed for 2 h. Afterwards, the solvent was removed in a vacuum, originating a red oil. This oil was extracted with n-hexane and we obtained a red extract that was cooled to 193.15 K. From the cooled solution we obtained red crystals characterized by 1H NMR, 13C NMR and elemental analysis (ca 0.33 g, 53% yield). Analysis found: C 44.8, H 7.8, N 14.6%; C10H20N3ClTi requires: C 45.2, H 7.6, N 15.8%. 1H NMR (300 MHz, C6D6): 2.28 (6H, s), 3.01 (12H, s), 5.93 (2H, s); 13C NMR (300 MHz, C6D6): 16.5 (CH3), 47.0 [Ti—N(CH3)2], 112.9 (ring C), 138.0 (ring C).
Crystals of Ti(DMP)(NMe2)2Cl were recovered from toluene and crystallized in the monoclinic space group P21/c. All non-H atoms were refined anisotropically. Methyl H atoms were positioned using an idealized methyl geometry, with torsion angle taken from the electron density [C—H = 0.96 Å and Uiso(H) = 1.5Ueq(C)]; in addition, Cp H atoms were placed in idealized aromatic positions [C—H = 0.93 Å and Uiso(H) = 1.3Ueq(C)]. Refinement was carried out based on F2 against all reflections. The weighted R factor wR and goodness of fit S are based on F2. The threshold expression of F2 > 2σ(F2) is used only for calculating R factors (gt) and is not relevant to the choice of reflections for refinement. No absorption correction was performed, because of the compound's unstability to air, moisture and temperature and its low diffracting power.
Data collection: CAD-4 Software (Enraf-Nonius, 1994); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SIR99 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999), PLATON (Spek, 2003) and enCIFer (Allen et al., 2004).
Fig. 1. View of Ti(DMP)Cl(NMe2)2 (30% probability displacement ellipsoids) with atomic labelling scheme |
[Ti(C2H6N)2(C6H8N)Cl] | F(000) = 560 |
Mr = 265.64 | Dx = 1.301 Mg m−3 |
Monoclinic, P21/c | Melting point: not measured K |
Hall symbol: -P 2ybc | Cu Kα radiation, λ = 1.5418 Å |
a = 8.421 (2) Å | Cell parameters from 25 reflections |
b = 11.915 (2) Å | θ = 18–22° |
c = 13.932 (2) Å | µ = 6.95 mm−1 |
β = 104.04 (2)° | T = 298 K |
V = 1356.1 (5) Å3 | Plate, red |
Z = 4 | 0.4 × 0.25 × 0.09 mm |
Enraf–Nonius CAD-4 diffractometer | θmax = 66.9°, θmin = 5.0° |
Radiation source: rotating anode, Turbo CAD4 | h = −10→1 |
ω/2θ scans | k = −1→14 |
3232 measured reflections | l = −16→16 |
2406 independent reflections | 3 standard reflections every 500 reflections |
1813 reflections with I > 2σ(I) | intensity decay: none |
Rint = 0.111 |
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)] = 0.049 | H-atom parameters constrained |
wR(F2) = 0.142 | w = 1/[σ2(Fo2) + (0.0708P)2 + 0.5834P] where P = (Fo2 + 2Fc2)/3 |
S = 1.06 | (Δ/σ)max = 0.031 |
2406 reflections | Δρmax = 0.52 e Å−3 |
143 parameters | Δρmin = −0.45 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: 0.0028 (5) |
[Ti(C2H6N)2(C6H8N)Cl] | V = 1356.1 (5) Å3 |
Mr = 265.64 | Z = 4 |
Monoclinic, P21/c | Cu Kα radiation |
a = 8.421 (2) Å | µ = 6.95 mm−1 |
b = 11.915 (2) Å | T = 298 K |
c = 13.932 (2) Å | 0.4 × 0.25 × 0.09 mm |
β = 104.04 (2)° |
Enraf–Nonius CAD-4 diffractometer | Rint = 0.111 |
3232 measured reflections | 3 standard reflections every 500 reflections |
2406 independent reflections | intensity decay: none |
1813 reflections with I > 2σ(I) |
R[F2 > 2σ(F2)] = 0.049 | 0 restraints |
wR(F2) = 0.142 | H-atom parameters constrained |
S = 1.06 | Δρmax = 0.52 e Å−3 |
2406 reflections | Δρmin = −0.45 e Å−3 |
143 parameters |
Experimental. All reactions and manipulations were carried out under an argon atmosphere, using standard Schlenk tube techniques, and the NMR samples were prepared in a Mbraun glove-box. All the solvents were dried with sodium and distilled over sodium-benzophenone, under nitrogen. Deuteriated benzene was dried with molecular sieves and deoxygenated by several freeze–pump–thaw cycles. The NMR spectra were recorded in deuteriated benzene on a Varian 300 MHz s pectrometer and referenced internally to the residual benzene resonance. Elemental analyses were performed by Laboratório de Análizes of Instituto Superior Técnico on a Fisons Instruments 1108 spectrometer. |
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. |
x | y | z | Uiso*/Ueq | ||
Ti1 | 0.17464 (8) | 0.77663 (5) | 0.10983 (4) | 0.0429 (2) | |
Cl1 | 0.12044 (16) | 0.79416 (9) | −0.06097 (7) | 0.0721 (4) | |
N1 | 0.4030 (4) | 0.8861 (3) | 0.1560 (2) | 0.0571 (8) | |
N2 | 0.2716 (4) | 0.6331 (3) | 0.1298 (3) | 0.0582 (8) | |
N3 | −0.0324 (4) | 0.7481 (3) | 0.1332 (2) | 0.0533 (8) | |
C1 | 0.3709 (5) | 0.8483 (3) | 0.2431 (3) | 0.0555 (9) | |
C2 | 0.2256 (5) | 0.8940 (3) | 0.2547 (3) | 0.0592 (10) | |
H2 | 0.1749 | 0.8785 | 0.3056 | 0.077* | |
C3 | 0.1685 (5) | 0.9684 (3) | 0.1752 (3) | 0.0577 (10) | |
H3 | 0.0741 | 1.0119 | 0.1637 | 0.075* | |
C4 | 0.2820 (5) | 0.9637 (3) | 0.1175 (3) | 0.0563 (9) | |
C5 | 0.4871 (6) | 0.7728 (4) | 0.3135 (4) | 0.0737 (13) | |
H5A | 0.5715 | 0.8172 | 0.3551 | 0.111* | |
H5B | 0.5354 | 0.7204 | 0.2766 | 0.111* | |
H5C | 0.4284 | 0.7326 | 0.3537 | 0.111* | |
C6 | 0.2886 (6) | 1.0326 (4) | 0.0281 (3) | 0.0749 (13) | |
H6A | 0.3705 | 1.0899 | 0.0467 | 0.112* | |
H6B | 0.1839 | 1.0669 | 0.0018 | 0.112* | |
H6C | 0.3156 | 0.9850 | −0.0212 | 0.112* | |
C7 | 0.4185 (6) | 0.6105 (5) | 0.0936 (4) | 0.0911 (17) | |
H7A | 0.5053 | 0.5854 | 0.1475 | 0.137* | |
H7B | 0.4516 | 0.6780 | 0.0661 | 0.137* | |
H7C | 0.3946 | 0.5535 | 0.0435 | 0.137* | |
C8 | 0.2314 (6) | 0.5392 (3) | 0.1856 (4) | 0.0771 (13) | |
H8A | 0.2035 | 0.4753 | 0.1428 | 0.116* | |
H8B | 0.1401 | 0.5587 | 0.2122 | 0.116* | |
H8C | 0.3241 | 0.5213 | 0.2387 | 0.116* | |
C9 | −0.1190 (6) | 0.6574 (4) | 0.0694 (4) | 0.0759 (13) | |
H9A | −0.1531 | 0.6012 | 0.1096 | 0.114* | |
H9B | −0.0471 | 0.6243 | 0.0334 | 0.114* | |
H9C | −0.2134 | 0.6877 | 0.0236 | 0.114* | |
C10 | −0.1390 (5) | 0.7927 (4) | 0.1926 (4) | 0.0703 (12) | |
H10A | −0.2413 | 0.8156 | 0.1499 | 0.105* | |
H10B | −0.0873 | 0.8562 | 0.2300 | 0.105* | |
H10C | −0.1584 | 0.7357 | 0.2371 | 0.105* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ti1 | 0.0614 (4) | 0.0355 (3) | 0.0337 (4) | 0.0016 (3) | 0.0153 (3) | −0.0011 (2) |
Cl1 | 0.1148 (9) | 0.0681 (7) | 0.0346 (5) | 0.0106 (6) | 0.0207 (5) | −0.0048 (4) |
N1 | 0.069 (2) | 0.0540 (19) | 0.0467 (19) | −0.0073 (15) | 0.0111 (15) | 0.0123 (15) |
N2 | 0.080 (2) | 0.0408 (16) | 0.058 (2) | 0.0050 (15) | 0.0245 (17) | 0.0036 (15) |
N3 | 0.0675 (19) | 0.0440 (16) | 0.0491 (19) | 0.0007 (14) | 0.0155 (14) | 0.0000 (14) |
C1 | 0.072 (2) | 0.053 (2) | 0.038 (2) | −0.0075 (19) | 0.0064 (17) | 0.0075 (17) |
C2 | 0.093 (3) | 0.049 (2) | 0.037 (2) | −0.007 (2) | 0.0166 (19) | −0.0038 (16) |
C3 | 0.084 (3) | 0.0397 (19) | 0.047 (2) | 0.0009 (19) | 0.0102 (19) | −0.0074 (17) |
C4 | 0.078 (3) | 0.0402 (19) | 0.047 (2) | −0.0088 (18) | 0.0091 (18) | 0.0074 (16) |
C5 | 0.079 (3) | 0.076 (3) | 0.058 (3) | −0.005 (2) | 0.000 (2) | 0.018 (2) |
C6 | 0.101 (3) | 0.061 (3) | 0.062 (3) | −0.013 (2) | 0.018 (2) | 0.021 (2) |
C7 | 0.101 (4) | 0.078 (3) | 0.110 (5) | 0.028 (3) | 0.055 (3) | 0.013 (3) |
C8 | 0.104 (3) | 0.045 (2) | 0.086 (4) | 0.005 (2) | 0.030 (3) | 0.012 (2) |
C9 | 0.079 (3) | 0.066 (3) | 0.080 (3) | −0.012 (2) | 0.013 (2) | −0.008 (3) |
C10 | 0.073 (3) | 0.079 (3) | 0.067 (3) | 0.007 (2) | 0.033 (2) | 0.010 (2) |
Ti1—N3 | 1.880 (3) | C4—C6 | 1.504 (5) |
Ti1—N2 | 1.886 (3) | C5—H5A | 0.9600 |
Ti1—N1 | 2.283 (3) | C5—H5B | 0.9600 |
Ti1—Cl1 | 2.3211 (12) | C5—H5C | 0.9600 |
Ti1—C1 | 2.328 (4) | C6—H6A | 0.9600 |
Ti1—C4 | 2.398 (4) | C6—H6B | 0.9600 |
Ti1—C2 | 2.407 (4) | C6—H6C | 0.9600 |
Ti1—C3 | 2.465 (4) | C7—H7A | 0.9600 |
N1—C1 | 1.382 (5) | C7—H7B | 0.9600 |
N1—C4 | 1.384 (5) | C7—H7C | 0.9600 |
N2—C8 | 1.448 (5) | C8—H8A | 0.9600 |
N2—C7 | 1.470 (5) | C8—H8B | 0.9600 |
N3—C10 | 1.462 (5) | C8—H8C | 0.9600 |
N3—C9 | 1.475 (5) | C9—H9A | 0.9600 |
C1—C2 | 1.384 (6) | C9—H9B | 0.9600 |
C1—C5 | 1.504 (6) | C9—H9C | 0.9600 |
C2—C3 | 1.408 (5) | C10—H10A | 0.9600 |
C2—H2 | 0.9300 | C10—H10B | 0.9600 |
C3—C4 | 1.392 (6) | C10—H10C | 0.9600 |
C3—H3 | 0.9300 | ||
N3—Ti1—N2 | 101.36 (14) | C4—C3—C2 | 106.1 (4) |
N3—Ti1—N1 | 143.85 (13) | C4—C3—Ti1 | 70.7 (2) |
N2—Ti1—N1 | 99.89 (14) | C2—C3—Ti1 | 70.9 (2) |
N3—Ti1—Cl1 | 103.51 (11) | C4—C3—H3 | 126.9 |
N2—Ti1—Cl1 | 101.72 (11) | C2—C3—H3 | 126.9 |
N1—Ti1—Cl1 | 100.36 (9) | Ti1—C3—H3 | 123.1 |
N3—Ti1—C1 | 115.91 (14) | N1—C4—C3 | 110.3 (3) |
N2—Ti1—C1 | 90.98 (15) | N1—C4—C6 | 120.9 (4) |
N1—Ti1—C1 | 34.85 (12) | C3—C4—C6 | 128.7 (4) |
Cl1—Ti1—C1 | 135.20 (10) | N1—C4—Ti1 | 68.31 (19) |
N3—Ti1—C4 | 121.03 (14) | C3—C4—Ti1 | 76.0 (2) |
N2—Ti1—C4 | 133.72 (15) | C6—C4—Ti1 | 124.0 (3) |
N1—Ti1—C4 | 34.28 (12) | C1—C5—H5A | 109.5 |
Cl1—Ti1—C4 | 86.58 (10) | C1—C5—H5B | 109.5 |
C1—Ti1—C4 | 55.69 (13) | H5A—C5—H5B | 109.5 |
N3—Ti1—C2 | 86.79 (15) | C1—C5—H5C | 109.5 |
N2—Ti1—C2 | 114.88 (15) | H5A—C5—H5C | 109.5 |
N1—Ti1—C2 | 57.68 (14) | H5B—C5—H5C | 109.5 |
Cl1—Ti1—C2 | 139.29 (10) | C4—C6—H6A | 109.5 |
C1—Ti1—C2 | 33.95 (14) | C4—C6—H6B | 109.5 |
C4—Ti1—C2 | 55.52 (13) | H6A—C6—H6B | 109.5 |
N3—Ti1—C3 | 90.00 (14) | C4—C6—H6C | 109.5 |
N2—Ti1—C3 | 146.41 (15) | H6A—C6—H6C | 109.5 |
N1—Ti1—C3 | 57.19 (13) | H6B—C6—H6C | 109.5 |
Cl1—Ti1—C3 | 106.20 (10) | N2—C7—H7A | 109.5 |
C1—Ti1—C3 | 55.91 (14) | N2—C7—H7B | 109.5 |
C4—Ti1—C3 | 33.22 (13) | H7A—C7—H7B | 109.5 |
C2—Ti1—C3 | 33.58 (13) | N2—C7—H7C | 109.5 |
C1—N1—C4 | 106.0 (3) | H7A—C7—H7C | 109.5 |
C1—N1—Ti1 | 74.3 (2) | H7B—C7—H7C | 109.5 |
C4—N1—Ti1 | 77.4 (2) | N2—C8—H8A | 109.5 |
C8—N2—C7 | 111.6 (4) | N2—C8—H8B | 109.5 |
C8—N2—Ti1 | 129.1 (3) | H8A—C8—H8B | 109.5 |
C7—N2—Ti1 | 119.1 (3) | N2—C8—H8C | 109.5 |
C10—N3—C9 | 109.0 (3) | H8A—C8—H8C | 109.5 |
C10—N3—Ti1 | 139.0 (3) | H8B—C8—H8C | 109.5 |
C9—N3—Ti1 | 111.9 (3) | N3—C9—H9A | 109.5 |
N1—C1—C2 | 110.0 (3) | N3—C9—H9B | 109.5 |
N1—C1—C5 | 122.2 (4) | H9A—C9—H9B | 109.5 |
C2—C1—C5 | 127.8 (4) | N3—C9—H9C | 109.5 |
N1—C1—Ti1 | 70.8 (2) | H9A—C9—H9C | 109.5 |
C2—C1—Ti1 | 76.2 (2) | H9B—C9—H9C | 109.5 |
C5—C1—Ti1 | 121.6 (3) | N3—C10—H10A | 109.5 |
C1—C2—C3 | 107.4 (4) | N3—C10—H10B | 109.5 |
C1—C2—Ti1 | 69.9 (2) | H10A—C10—H10B | 109.5 |
C3—C2—Ti1 | 75.5 (2) | N3—C10—H10C | 109.5 |
C1—C2—H2 | 126.3 | H10A—C10—H10C | 109.5 |
C3—C2—H2 | 126.3 | H10B—C10—H10C | 109.5 |
Ti1—C2—H2 | 120.1 | ||
N3—Ti1—N1—C1 | 48.0 (3) | C3—Ti1—C1—C5 | 163.3 (4) |
N2—Ti1—N1—C1 | −77.3 (2) | N1—C1—C2—C3 | −3.5 (5) |
Cl1—Ti1—N1—C1 | 178.7 (2) | C5—C1—C2—C3 | 173.8 (4) |
C4—Ti1—N1—C1 | 110.8 (3) | Ti1—C1—C2—C3 | −66.8 (3) |
C2—Ti1—N1—C1 | 36.0 (2) | N1—C1—C2—Ti1 | 63.3 (3) |
C3—Ti1—N1—C1 | 76.1 (2) | C5—C1—C2—Ti1 | −119.5 (4) |
N3—Ti1—N1—C4 | −62.8 (3) | N3—Ti1—C2—C1 | 150.1 (2) |
N2—Ti1—N1—C4 | 171.9 (2) | N2—Ti1—C2—C1 | 49.1 (3) |
Cl1—Ti1—N1—C4 | 67.9 (2) | N1—Ti1—C2—C1 | −37.0 (2) |
C1—Ti1—N1—C4 | −110.8 (3) | Cl1—Ti1—C2—C1 | −102.8 (2) |
C2—Ti1—N1—C4 | −74.9 (2) | C4—Ti1—C2—C1 | −78.2 (3) |
C3—Ti1—N1—C4 | −34.8 (2) | C3—Ti1—C2—C1 | −115.0 (4) |
N3—Ti1—N2—C8 | −22.4 (4) | N3—Ti1—C2—C3 | −94.8 (3) |
N1—Ti1—N2—C8 | 128.1 (4) | N2—Ti1—C2—C3 | 164.1 (2) |
Cl1—Ti1—N2—C8 | −129.0 (4) | N1—Ti1—C2—C3 | 78.1 (3) |
C1—Ti1—N2—C8 | 94.3 (4) | Cl1—Ti1—C2—C3 | 12.2 (3) |
C4—Ti1—N2—C8 | 134.5 (4) | C1—Ti1—C2—C3 | 115.0 (4) |
C2—Ti1—N2—C8 | 69.3 (4) | C4—Ti1—C2—C3 | 36.8 (2) |
C3—Ti1—N2—C8 | 85.2 (5) | C1—C2—C3—C4 | 0.6 (4) |
N3—Ti1—N2—C7 | 163.9 (4) | Ti1—C2—C3—C4 | −62.4 (3) |
N1—Ti1—N2—C7 | −45.5 (4) | C1—C2—C3—Ti1 | 63.1 (3) |
Cl1—Ti1—N2—C7 | 57.4 (4) | N3—Ti1—C3—C4 | −160.2 (3) |
C1—Ti1—N2—C7 | −79.4 (4) | N2—Ti1—C3—C4 | 88.9 (3) |
C4—Ti1—N2—C7 | −39.2 (4) | N1—Ti1—C3—C4 | 35.9 (2) |
C2—Ti1—N2—C7 | −104.3 (4) | Cl1—Ti1—C3—C4 | −56.1 (2) |
C3—Ti1—N2—C7 | −88.5 (4) | C1—Ti1—C3—C4 | 77.9 (3) |
N2—Ti1—N3—C10 | 128.6 (4) | C2—Ti1—C3—C4 | 115.6 (4) |
N1—Ti1—N3—C10 | 3.7 (6) | N3—Ti1—C3—C2 | 84.2 (3) |
Cl1—Ti1—N3—C10 | −126.3 (4) | N2—Ti1—C3—C2 | −26.7 (4) |
C1—Ti1—N3—C10 | 31.8 (5) | N1—Ti1—C3—C2 | −79.7 (3) |
C4—Ti1—N3—C10 | −32.1 (5) | Cl1—Ti1—C3—C2 | −171.7 (2) |
C2—Ti1—N3—C10 | 13.8 (4) | C1—Ti1—C3—C2 | −37.7 (2) |
C3—Ti1—N3—C10 | −19.6 (4) | C4—Ti1—C3—C2 | −115.6 (4) |
N2—Ti1—N3—C9 | −55.5 (3) | C1—N1—C4—C3 | −4.5 (4) |
N1—Ti1—N3—C9 | 179.6 (3) | Ti1—N1—C4—C3 | 64.9 (3) |
Cl1—Ti1—N3—C9 | 49.7 (3) | C1—N1—C4—C6 | 172.9 (4) |
C1—Ti1—N3—C9 | −152.2 (3) | Ti1—N1—C4—C6 | −117.6 (4) |
C4—Ti1—N3—C9 | 143.9 (3) | C1—N1—C4—Ti1 | −69.4 (2) |
C2—Ti1—N3—C9 | −170.2 (3) | C2—C3—C4—N1 | 2.4 (4) |
C3—Ti1—N3—C9 | 156.4 (3) | Ti1—C3—C4—N1 | −60.1 (3) |
C4—N1—C1—C2 | 4.9 (4) | C2—C3—C4—C6 | −174.8 (4) |
Ti1—N1—C1—C2 | −66.7 (3) | Ti1—C3—C4—C6 | 122.7 (4) |
C4—N1—C1—C5 | −172.5 (4) | C2—C3—C4—Ti1 | 62.5 (3) |
Ti1—N1—C1—C5 | 115.9 (4) | N3—Ti1—C4—N1 | 142.2 (2) |
C4—N1—C1—Ti1 | 71.6 (2) | N2—Ti1—C4—N1 | −11.1 (3) |
N3—Ti1—C1—N1 | −150.8 (2) | Cl1—Ti1—C4—N1 | −114.1 (2) |
N2—Ti1—C1—N1 | 106.0 (2) | C1—Ti1—C4—N1 | 40.3 (2) |
Cl1—Ti1—C1—N1 | −1.8 (3) | C2—Ti1—C4—N1 | 81.7 (3) |
C4—Ti1—C1—N1 | −39.6 (2) | C3—Ti1—C4—N1 | 119.0 (3) |
C2—Ti1—C1—N1 | −117.3 (3) | N3—Ti1—C4—C3 | 23.3 (3) |
C3—Ti1—C1—N1 | −80.0 (2) | N2—Ti1—C4—C3 | −130.1 (3) |
N3—Ti1—C1—C2 | −33.6 (3) | N1—Ti1—C4—C3 | −119.0 (3) |
N2—Ti1—C1—C2 | −136.7 (2) | Cl1—Ti1—C4—C3 | 127.0 (2) |
N1—Ti1—C1—C2 | 117.3 (3) | C1—Ti1—C4—C3 | −78.7 (3) |
Cl1—Ti1—C1—C2 | 115.5 (2) | C2—Ti1—C4—C3 | −37.2 (2) |
C4—Ti1—C1—C2 | 77.7 (3) | N3—Ti1—C4—C6 | −104.3 (4) |
C3—Ti1—C1—C2 | 37.2 (2) | N2—Ti1—C4—C6 | 102.4 (4) |
N3—Ti1—C1—C5 | 92.5 (4) | N1—Ti1—C4—C6 | 113.5 (5) |
N2—Ti1—C1—C5 | −10.6 (4) | Cl1—Ti1—C4—C6 | −0.6 (4) |
N1—Ti1—C1—C5 | −116.6 (4) | C1—Ti1—C4—C6 | 153.8 (4) |
Cl1—Ti1—C1—C5 | −118.4 (3) | C2—Ti1—C4—C6 | −164.8 (4) |
C4—Ti1—C1—C5 | −156.2 (4) | C3—Ti1—C4—C6 | −127.5 (5) |
C2—Ti1—C1—C5 | 126.1 (4) |
Experimental details
Crystal data | |
Chemical formula | [Ti(C2H6N)2(C6H8N)Cl] |
Mr | 265.64 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 298 |
a, b, c (Å) | 8.421 (2), 11.915 (2), 13.932 (2) |
β (°) | 104.04 (2) |
V (Å3) | 1356.1 (5) |
Z | 4 |
Radiation type | Cu Kα |
µ (mm−1) | 6.95 |
Crystal size (mm) | 0.4 × 0.25 × 0.09 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3232, 2406, 1813 |
Rint | 0.111 |
(sin θ/λ)max (Å−1) | 0.597 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.049, 0.142, 1.06 |
No. of reflections | 2406 |
No. of parameters | 143 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.52, −0.45 |
Computer programs: CAD-4 Software (Enraf-Nonius, 1994), CAD-4 Software, XCAD4 (Harms & Wocadlo, 1995), SIR99 (Altomare et al., 1999), SHELXL97 (Sheldrick, 1997), WinGX (Farrugia, 1999), PLATON (Spek, 2003) and enCIFer (Allen et al., 2004).
Ti1—N3 | 1.880 (3) | Ti1—C3 | 2.465 (4) |
Ti1—N2 | 1.886 (3) | N1—C1 | 1.382 (5) |
Ti1—N1 | 2.283 (3) | N1—C4 | 1.384 (5) |
Ti1—Cl1 | 2.3211 (12) | C1—C2 | 1.384 (6) |
Ti1—C1 | 2.328 (4) | C2—C3 | 1.408 (5) |
Ti1—C4 | 2.398 (4) | C3—C4 | 1.392 (6) |
Ti1—C2 | 2.407 (4) | ||
N3—Ti1—N2 | 101.36 (14) | N2—Ti1—Cl1 | 101.72 (11) |
N3—Ti1—Cl1 | 103.51 (11) |
Ti—N (Å) | Ti—Cβ (Å) | |
Ti(η5-DMP)(NMe2)2Cl | 2.283 (3) | 2.465 (4) |
Ti(η5-TMP)(NMe2)Cl2 | 2.149 (7) | 2.580 (9) |
Ti(η5-TMP)Cl2 | 2.181 (6) | 2.426 (6) |
Ti(η5-Cp)(η5-TMP)Cl2 | 2.254 (9) | 2.549 (12) |
Ti(η5-TMP)(SPh)3 | 2.168 (10) | 2.460 (14) |
Ti(η5-TMP)(CH3)Cl2 | 2.188 (2) | 2.437 (1) |
Ti(η5-di-tert-butylpyrrolyl)Cl3 | 2.249 (11) | 2,344 (14) |
Organometalic complexes with pentahapto pyrrolyl (pyr*) ligands have been attracting considerably more attention in the past few years (Tanski & Parkin, 2002; Llop et al., 2002), including from our own group (Dias et al., 1997; Dias et al., 1998; Dias et al., 2001; Dias et al., 2003; Ascenso et al., 2003). A relevant feature of these complexes is the possibility of inducing changes in the pyrrolyl hapticity by means of changing the other ligands in the coordination sphere. The series Ti(pyr*)(NMe2)4-nCln is very useful for this kind of study because the progressive substitution of the amide ligands by chloride forces a change towards a more pentahapto coordination of the pyrrolyl ligand. This change can also be followed by 13C NMR studies on the ring C atoms, allowing a comparison between the deshielding effect felt by these atoms and the coordination mode.
The title complex, Ti(DMP)(NMe2)2Cl, (I), is unusual because its solid-state structure contains a pentahapto pyrrolyl ring while the deshielding effect felt by the ring C atoms is very low, roughly 10 p.p.m. relative to the free pro-ligand, which may indicate that this kind of hapticity may be more common than anticipated, based on 13C NMR data.
Complex (I) crystallizes in a monoclinic system, space group P21/c. The molecular structure is depicted in Fig. 1. The coordination geometry can be best described as a piano-stool arrangement, a pseudo-tetrahedral geometry being confirmed by the angles around the metal centre (see Table 1) as well as by the X—Ti—Cp(centroid) angles [Cl1—Ti1—Cp(centroid) = 115.5 (8)°, N—Ti—Cp(centroid) = 119.9 (8)°; N—Ti—Cp(centroid) = 112.7 (8)°]. Although these angles all have values around 109° (tetrahedral ideal geometry), the angles involving the Cp centroid are considerably larger than those involving any two of the other ligands.
The attribution of a η5 hapticity to the ligand ring is based on the Ti1—Cn (n = 1–4) and Ti1—N1 bond lengths (Table 1). Table 2 gives the Ti—N and Ti—C (maximum) bond lengths for similar compounds (Galvão, 1999; Kuhn et al., 1992), where η5 hapticity was proposed on the basis of the X-ray structures. The difference between these two bond lengths in the present structure [0.184 (4) Å] is smaller than the differences found for several of these compounds. This discrepancy results in part from the fact that the Ti—N bond in (I) is longer than that in the other compounds considered?. Other important parameters considered in the attribution of this hapticity are the slip parameter and the fold angle. The slip parameter (Δ) is defined as the difference between the average bond lengths of the metal to the C atoms opposed to the N atom and the average bond lengths of the metal to the C atoms adjacent to the N atom, while the fold angle (FA) is defined as the angle between the C1/N1/C4 and C1/C2/C3/C4 planes (Cadierno et al., 1999). The values obtained [0.073 (9) Å for Δ and 4.6 (6)° for FA] are well within the values accepted for η5 Cp compounds. The N1—Cp(centroid)—Ti1 angle is also close to 90° [84.5 (7)°], as expected for an η5 ring; this angle is larger than that for other compounds, such as Ti(η5-TMP)(NMe2)Cl2 [75.3 (7)°], to which an η5 coordination has been unequivocally attributed (Galvão, 1999). Despite the η5coordination, the relative Ti1—Cn (n = 1–4) bond lengths are indicative that the ring presents a slippage, with one side of the ring, C3—C4, above the other.
The 1H and 13C room-temperature NMR spectra of Ti(η5-2,5-dimethylpyrrolyl)(NMe2)2Cl supply information in part contradictory to the X-ray structure. They show the β H atoms and the two α C atoms originating both two peaks, which is in good agreement with the loss of the symmetry plane usually formed by atoms N1 and Ti1 and the Cp centroid caused by the slippage of the ring. However the deshielding values observed for the ring C atoms (6.64 p.p.m. for atoms C2 and C5, and 12.49 p.p.m. for atoms C3 and C4) are the lowest ever reported for an η5 pyrrolyl, indicating the possibility of a coordination intermediate between N-σ (where no deshielding for atoms C3 and C4 should be detected) and η5, as proposed for Ti(2,3,4,5-tetramethylpyrrolyl)(NMe2)2Cl (Galvão, 1999).
The variation of the splitting between the 13C peaks of C3 and C4 with temperature was analysed and a merging temperature of 285 K was determined; this result indicates the existence of a fluxional process above this temperature, passing through an intermediate involving simultaneously a metal—azaallyl and a metal—olefin bond (see the scheme below); this mechanism would explain the low values of deshielding observed.
The value of the Gibbs free energy for this process (ΔGc = 71.61 kJ mol−1) was calculated using the Eyring equation (Δµ= 3.9 Hz, kc = 17.33 s−1 and Tc= 285.15 K).