Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807042444/bv2069sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807042444/bv2069Isup2.hkl |
CCDC reference: 663560
Key indicators
- Single-crystal X-ray study
- T = 108 K
- Mean (C-C) = 0.005 Å
- R factor = 0.032
- wR factor = 0.081
- Data-to-parameter ratio = 18.8
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent ..... ? PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X) Rh1 - Cl2 .. 8.26 su PLAT480_ALERT_4_C Long H...A H-Bond Reported H22 .. CL1 .. 2.88 Ang.
Alert level G PLAT794_ALERT_5_G Check Predicted Bond Valency for Rh1 (3) 3.09
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 3 ALERT level C = Check and explain 1 ALERT level G = General alerts; check 1 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 1 ALERT type 4 Improvement, methodology, query or suggestion 1 ALERT type 5 Informative message, check
For related literature, see: Albinati et al. (1999); Cushing et al. (2006); Nicto et al. (2005).
fac-[RhCl3(pzH)3] (I) was prepared by treating 50.5 mg RhCl3 .3H2O (0.19 mmol) in 0.9 ml 2-propanol/water (5:1) with 3 equivalents of pyrazole (40.2 mg, 0.59 mmol). After stirring for 1.5 h, the resulting yellow precipitate was removed by centrifugation and washed with 2 ml of 2-propanol to afford fac-[RhCl3(pzH)3] in 17% yield (13.7 mg). Elemental anlysis (Vario EL) for C9H12Cl3N6Rh .H2O (M = 431.5): C 25.4 (calc. 25.7), H 3.2 (calc. 3.4), N 19.4 (calc. 19.3). FAB MS on a VG Autospec: m/z 435(3%) [M+Na]+, 377(15%) [M—Cl]+. 1H NMR (CDCl3) on a Bruker DRX 400: δ 6.57 (t, 3H, pzH-b), 6.88 (d, 3H, pzH-c), 7.89 (d, 3H, pyH-a), 12.48 (d, 3H, NH). Suitable crystals for X-ray analysis were obtained by slow evaporation of a methanol solution of (I).
H atoms were constrained to idealized positions and refined using a riding model, with C—H distances of 0.93 Å and N—H distances of 0.86 Å; Uiso(H) = 1.2 Uiso(C) for the former and Uiso(H) = 1.2 Uiso(N) for the latter protons.
The complexes mer-[MCl3(Me2pzH)3] .CH3OH (M = Rh, Ir; Me2pzH = 3,5-dimethylpyrazole) have been prepared by treating MCl3 .xH2O with three equivalents of 3,5-dimethylpyrazole in methanol at 85°C (Cushing et al., 2006). Only the mer-isomers were obtained on subsequent recrystallization from methanol solution. mer-[RhCl3(Me2pzH)3] has also been characterized as a decomposition product of the reaction of [RhCl3(CH3CN)3] with Tl[HB(Me2pz)]3 (Albinati et al., 1999). A facial tris(dimethylpyrazole) ReI complex fac-[Re(CO)3(Me2pzH)3][B(Ar)4] (Ar = 3,5-bis(trifluoromethylphenyl)) is also known (Nicto et al., 2005).
We now report the crystal structure of fac-[RhCl3(pzH)3] (I), which was obtained by treating RhCl3 .3H2O in a 2-propanol/water mixture with three equivalents of pyrazole. (I) was recrystallized as the fac-isomer from methanol solution and exhibits the expected 1H NMR resonances at 6.57 (t), 6.88 (d) and 7.89 (d) for the C—H protons and 12.48 (d) for the N—H protons of the pure isomer in CDCl3 solution. A 2:1 mixture of the fac and mer isomers is observed after 5 h in methanol solution. As depicted in Fig. 1, the pyrazole ligands adopt a propellor-like arrangement in (I) and participate in intramolecular N—H···Cl hydrogen bonds (Table 1) to the nearest chloride ligand. Their best planes exhibit respective dihedral angles of 26.83 (17), 2.03 (10) and 18.83 (14)° to the planes containing their coordinating nitrogen atoms, Rh1 and the acceptor Cl atoms of their N—H···Cl interactions. The molecules are linked into a network by intermolecular N—H···Cl and C—H···Cl hydrogen bonds (Fig. 2).
For related literature, see: Albinati et al. (1999); Cushing et al. (2006); Nicto et al. (2005).
Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL-Plus (Sheldrick, 1995); software used to prepare material for publication: SHELXL97.
[RhCl3(C3H4N2)3] | F(000) = 816 |
Mr = 413.51 | Dx = 1.959 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 14706 reflections |
a = 8.2041 (3) Å | θ = 2.5–27.5° |
b = 11.9243 (4) Å | µ = 1.78 mm−1 |
c = 14.5839 (5) Å | T = 108 K |
β = 100.624 (3)° | Prismatic, orange |
V = 1402.26 (8) Å3 | 0.52 × 0.18 × 0.13 mm |
Z = 4 |
Oxford Diffraction Sapphire2 CCD diffractometer | 3236 independent reflections |
Radiation source: fine-focus sealed tube | 2701 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
1109 images at 1.0 deg in ω and 20 s scans | θmax = 27.6°, θmin = 2.8° |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) | h = −10→10 |
Tmin = 0.692, Tmax = 0.802 | k = −15→14 |
25826 measured reflections | l = −19→18 |
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)] = 0.032 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.081 | H-atom parameters constrained |
S = 1.05 | w = 1/[σ2(Fo2) + (0.0483P)2] where P = (Fo2 + 2Fc2)/3 |
3236 reflections | (Δ/σ)max = 0.001 |
172 parameters | Δρmax = 0.88 e Å−3 |
0 restraints | Δρmin = −0.78 e Å−3 |
[RhCl3(C3H4N2)3] | V = 1402.26 (8) Å3 |
Mr = 413.51 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 8.2041 (3) Å | µ = 1.78 mm−1 |
b = 11.9243 (4) Å | T = 108 K |
c = 14.5839 (5) Å | 0.52 × 0.18 × 0.13 mm |
β = 100.624 (3)° |
Oxford Diffraction Sapphire2 CCD diffractometer | 3236 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) | 2701 reflections with I > 2σ(I) |
Tmin = 0.692, Tmax = 0.802 | Rint = 0.041 |
25826 measured reflections |
R[F2 > 2σ(F2)] = 0.032 | 0 restraints |
wR(F2) = 0.081 | H-atom parameters constrained |
S = 1.05 | Δρmax = 0.88 e Å−3 |
3236 reflections | Δρmin = −0.78 e Å−3 |
172 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 | ||
Rh1 | −0.00400 (3) | 0.990704 (18) | 0.245999 (14) | 0.01730 (9) | |
Cl1 | 0.19460 (10) | 0.92389 (8) | 0.16155 (5) | 0.03188 (19) | |
Cl2 | 0.01555 (10) | 0.82640 (6) | 0.33384 (5) | 0.02876 (18) | |
Cl3 | 0.19940 (9) | 1.07268 (7) | 0.35894 (5) | 0.02689 (17) | |
N11 | −0.1773 (3) | 1.0492 (2) | 0.31679 (17) | 0.0195 (5) | |
N12 | −0.1894 (4) | 1.0192 (2) | 0.40354 (19) | 0.0319 (6) | |
H12 | −0.1245 | 0.9729 | 0.4377 | 0.038* | |
C13 | −0.3195 (5) | 1.0729 (3) | 0.4296 (2) | 0.0358 (8) | |
H13 | −0.3541 | 1.0660 | 0.4866 | 0.043* | |
C14 | −0.3900 (4) | 1.1389 (3) | 0.3568 (2) | 0.0290 (7) | |
H14 | −0.4817 | 1.1855 | 0.3540 | 0.035* | |
C15 | −0.2986 (4) | 1.1227 (2) | 0.2887 (2) | 0.0201 (6) | |
H15 | −0.3182 | 1.1580 | 0.2309 | 0.024* | |
N21 | −0.0229 (3) | 1.1355 (2) | 0.16938 (17) | 0.0211 (5) | |
N22 | 0.0733 (3) | 1.2255 (2) | 0.19646 (18) | 0.0258 (6) | |
H22 | 0.1480 | 1.2284 | 0.2463 | 0.031* | |
C23 | 0.0374 (4) | 1.3100 (3) | 0.1356 (2) | 0.0278 (7) | |
H23 | 0.0873 | 1.3803 | 0.1398 | 0.033* | |
C24 | −0.0870 (4) | 1.2733 (3) | 0.0658 (2) | 0.0271 (7) | |
H24 | −0.1381 | 1.3130 | 0.0135 | 0.033* | |
C25 | −0.1203 (4) | 1.1638 (3) | 0.0903 (2) | 0.0267 (7) | |
H25 | −0.1997 | 1.1173 | 0.0558 | 0.032* | |
N31 | −0.1879 (3) | 0.9203 (2) | 0.14972 (17) | 0.0208 (5) | |
N32 | −0.1648 (4) | 0.8932 (2) | 0.06342 (18) | 0.0292 (6) | |
H32 | −0.0731 | 0.9016 | 0.0436 | 0.035* | |
C33 | −0.3044 (5) | 0.8512 (3) | 0.0127 (2) | 0.0390 (9) | |
H33 | −0.3184 | 0.8265 | −0.0488 | 0.047* | |
C34 | −0.4233 (4) | 0.8513 (3) | 0.0680 (3) | 0.0379 (8) | |
H34 | −0.5325 | 0.8268 | 0.0520 | 0.045* | |
C35 | −0.3450 (4) | 0.8960 (3) | 0.1528 (2) | 0.0297 (7) | |
H35 | −0.3952 | 0.9073 | 0.2043 | 0.036* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Rh1 | 0.01787 (13) | 0.02047 (13) | 0.01265 (12) | 0.00115 (8) | 0.00043 (8) | 0.00065 (8) |
Cl1 | 0.0259 (4) | 0.0454 (5) | 0.0252 (4) | 0.0060 (3) | 0.0069 (3) | −0.0037 (3) |
Cl2 | 0.0346 (4) | 0.0227 (4) | 0.0259 (4) | 0.0059 (3) | −0.0025 (3) | 0.0035 (3) |
Cl3 | 0.0261 (4) | 0.0300 (4) | 0.0206 (3) | −0.0029 (3) | −0.0061 (3) | 0.0014 (3) |
N11 | 0.0220 (12) | 0.0179 (12) | 0.0172 (11) | −0.0001 (9) | 0.0001 (9) | 0.0013 (9) |
N12 | 0.0423 (17) | 0.0324 (15) | 0.0203 (13) | 0.0064 (13) | 0.0040 (12) | 0.0056 (11) |
C13 | 0.053 (2) | 0.0321 (18) | 0.0272 (17) | 0.0060 (16) | 0.0211 (16) | 0.0030 (14) |
C14 | 0.0290 (17) | 0.0246 (16) | 0.0361 (18) | 0.0027 (13) | 0.0126 (14) | −0.0006 (13) |
C15 | 0.0221 (14) | 0.0204 (14) | 0.0174 (13) | 0.0029 (11) | 0.0021 (11) | 0.0038 (11) |
N21 | 0.0177 (12) | 0.0254 (13) | 0.0198 (12) | −0.0026 (10) | 0.0025 (9) | 0.0007 (10) |
N22 | 0.0267 (13) | 0.0303 (14) | 0.0189 (12) | −0.0040 (11) | 0.0003 (10) | 0.0018 (10) |
C23 | 0.0324 (17) | 0.0286 (17) | 0.0237 (15) | −0.0048 (13) | 0.0084 (13) | 0.0039 (12) |
C24 | 0.0305 (16) | 0.0307 (17) | 0.0199 (14) | 0.0027 (13) | 0.0040 (12) | 0.0066 (12) |
C25 | 0.0267 (16) | 0.0323 (17) | 0.0197 (14) | −0.0022 (13) | 0.0010 (12) | 0.0024 (12) |
N31 | 0.0238 (12) | 0.0207 (12) | 0.0167 (11) | −0.0001 (10) | 0.0006 (9) | 0.0000 (9) |
N32 | 0.0337 (15) | 0.0347 (15) | 0.0187 (12) | −0.0005 (12) | 0.0036 (11) | −0.0052 (11) |
C33 | 0.044 (2) | 0.040 (2) | 0.0280 (18) | 0.0013 (16) | −0.0076 (15) | −0.0123 (15) |
C34 | 0.0285 (18) | 0.038 (2) | 0.042 (2) | −0.0012 (15) | −0.0078 (15) | −0.0092 (16) |
C35 | 0.0249 (16) | 0.0360 (18) | 0.0275 (16) | −0.0022 (13) | 0.0026 (13) | −0.0042 (14) |
Rh1—N11 | 2.029 (3) | N22—C23 | 1.339 (4) |
Rh1—N31 | 2.043 (2) | N22—H22 | 0.8600 |
Rh1—N21 | 2.047 (3) | C23—C24 | 1.373 (5) |
Rh1—Cl2 | 2.3302 (8) | C23—H23 | 0.9300 |
Rh1—Cl3 | 2.3323 (7) | C24—C25 | 1.394 (5) |
Rh1—Cl1 | 2.3550 (8) | C24—H24 | 0.9300 |
N11—C15 | 1.333 (4) | C25—H25 | 0.9300 |
N11—N12 | 1.336 (4) | N31—C35 | 1.330 (4) |
N12—C13 | 1.358 (5) | N31—N32 | 1.346 (3) |
N12—H12 | 0.8600 | N32—C33 | 1.341 (4) |
C13—C14 | 1.363 (5) | N32—H32 | 0.8600 |
C13—H13 | 0.9300 | C33—C34 | 1.375 (6) |
C14—C15 | 1.363 (4) | C33—H33 | 0.9300 |
C14—H14 | 0.9300 | C34—C35 | 1.392 (5) |
C15—H15 | 0.9300 | C34—H34 | 0.9300 |
N21—C25 | 1.320 (4) | C35—H35 | 0.9300 |
N21—N22 | 1.348 (4) | ||
N11—Rh1—N31 | 89.60 (10) | C25—N21—N22 | 106.3 (3) |
N11—Rh1—N21 | 89.87 (10) | C25—N21—Rh1 | 131.7 (2) |
N31—Rh1—N21 | 89.96 (10) | N22—N21—Rh1 | 122.04 (18) |
N11—Rh1—Cl2 | 89.61 (7) | C23—N22—N21 | 111.0 (3) |
N31—Rh1—Cl2 | 89.98 (7) | C23—N22—H22 | 124.5 |
N21—Rh1—Cl2 | 179.48 (7) | N21—N22—H22 | 124.5 |
N11—Rh1—Cl3 | 88.49 (7) | N22—C23—C24 | 107.1 (3) |
N31—Rh1—Cl3 | 178.08 (7) | N22—C23—H23 | 126.4 |
N21—Rh1—Cl3 | 90.25 (7) | C24—C23—H23 | 126.4 |
Cl2—Rh1—Cl3 | 89.79 (3) | C23—C24—C25 | 105.2 (3) |
N11—Rh1—Cl1 | 179.07 (7) | C23—C24—H24 | 127.4 |
N31—Rh1—Cl1 | 89.77 (7) | C25—C24—H24 | 127.4 |
N21—Rh1—Cl1 | 89.43 (7) | N21—C25—C24 | 110.3 (3) |
Cl2—Rh1—Cl1 | 91.08 (3) | N21—C25—H25 | 124.8 |
Cl3—Rh1—Cl1 | 92.14 (3) | C24—C25—H25 | 124.8 |
C15—N11—N12 | 106.6 (3) | C35—N31—N32 | 106.5 (3) |
C15—N11—Rh1 | 128.6 (2) | C35—N31—Rh1 | 131.6 (2) |
N12—N11—Rh1 | 124.8 (2) | N32—N31—Rh1 | 121.9 (2) |
N11—N12—C13 | 109.8 (3) | C33—N32—N31 | 110.6 (3) |
N11—N12—H12 | 125.1 | C33—N32—H32 | 124.7 |
C13—N12—H12 | 125.1 | N31—N32—H32 | 124.7 |
N12—C13—C14 | 107.2 (3) | N32—C33—C34 | 107.6 (3) |
N12—C13—H13 | 126.4 | N32—C33—H33 | 126.2 |
C14—C13—H13 | 126.4 | C34—C33—H33 | 126.2 |
C13—C14—C15 | 105.9 (3) | C33—C34—C35 | 105.1 (3) |
C13—C14—H14 | 127.0 | C33—C34—H34 | 127.4 |
C15—C14—H14 | 127.0 | C35—C34—H34 | 127.4 |
N11—C15—C14 | 110.5 (3) | N31—C35—C34 | 110.2 (3) |
N11—C15—H15 | 124.8 | N31—C35—H35 | 124.9 |
C14—C15—H15 | 124.8 | C34—C35—H35 | 124.9 |
D—H···A | D—H | H···A | D···A | D—H···A |
N32—H32···Cl1 | 0.86 | 2.54 | 3.053 (3) | 119 |
N12—H12···Cl2 | 0.86 | 2.70 | 3.127 (3) | 112 |
N22—H22···Cl3 | 0.86 | 2.46 | 3.017 (3) | 123 |
C15—H15···Cl2i | 0.93 | 2.64 | 3.330 (3) | 131 |
C33—H33···Cl2ii | 0.93 | 2.69 | 3.471 (3) | 142 |
C24—H24···Cl3iii | 0.93 | 2.76 | 3.688 (3) | 178 |
N22—H22···Cl1iv | 0.86 | 2.88 | 3.472 (3) | 128 |
Symmetry codes: (i) −x−1/2, y+1/2, −z+1/2; (ii) x−1/2, −y+3/2, z−1/2; (iii) x−1/2, −y+5/2, z−1/2; (iv) −x+1/2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [RhCl3(C3H4N2)3] |
Mr | 413.51 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 108 |
a, b, c (Å) | 8.2041 (3), 11.9243 (4), 14.5839 (5) |
β (°) | 100.624 (3) |
V (Å3) | 1402.26 (8) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.78 |
Crystal size (mm) | 0.52 × 0.18 × 0.13 |
Data collection | |
Diffractometer | Oxford Diffraction Sapphire2 CCD |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2006) |
Tmin, Tmax | 0.692, 0.802 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 25826, 3236, 2701 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.652 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.032, 0.081, 1.05 |
No. of reflections | 3236 |
No. of parameters | 172 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.88, −0.78 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), CrysAlis RED, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL-Plus (Sheldrick, 1995), SHELXL97.
D—H···A | D—H | H···A | D···A | D—H···A |
N32—H32···Cl1 | 0.86 | 2.54 | 3.053 (3) | 119.0 |
N12—H12···Cl2 | 0.86 | 2.70 | 3.127 (3) | 111.8 |
N22—H22···Cl3 | 0.86 | 2.46 | 3.017 (3) | 122.8 |
C15—H15···Cl2i | 0.93 | 2.64 | 3.330 (3) | 131.3 |
C33—H33···Cl2ii | 0.93 | 2.69 | 3.471 (3) | 141.7 |
C24—H24···Cl3iii | 0.93 | 2.76 | 3.688 (3) | 177.9 |
N22—H22···Cl1iv | 0.86 | 2.88 | 3.472 (3) | 128.0 |
Symmetry codes: (i) −x−1/2, y+1/2, −z+1/2; (ii) x−1/2, −y+3/2, z−1/2; (iii) x−1/2, −y+5/2, z−1/2; (iv) −x+1/2, y+1/2, −z+1/2. |
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The complexes mer-[MCl3(Me2pzH)3] .CH3OH (M = Rh, Ir; Me2pzH = 3,5-dimethylpyrazole) have been prepared by treating MCl3 .xH2O with three equivalents of 3,5-dimethylpyrazole in methanol at 85°C (Cushing et al., 2006). Only the mer-isomers were obtained on subsequent recrystallization from methanol solution. mer-[RhCl3(Me2pzH)3] has also been characterized as a decomposition product of the reaction of [RhCl3(CH3CN)3] with Tl[HB(Me2pz)]3 (Albinati et al., 1999). A facial tris(dimethylpyrazole) ReI complex fac-[Re(CO)3(Me2pzH)3][B(Ar)4] (Ar = 3,5-bis(trifluoromethylphenyl)) is also known (Nicto et al., 2005).
We now report the crystal structure of fac-[RhCl3(pzH)3] (I), which was obtained by treating RhCl3 .3H2O in a 2-propanol/water mixture with three equivalents of pyrazole. (I) was recrystallized as the fac-isomer from methanol solution and exhibits the expected 1H NMR resonances at 6.57 (t), 6.88 (d) and 7.89 (d) for the C—H protons and 12.48 (d) for the N—H protons of the pure isomer in CDCl3 solution. A 2:1 mixture of the fac and mer isomers is observed after 5 h in methanol solution. As depicted in Fig. 1, the pyrazole ligands adopt a propellor-like arrangement in (I) and participate in intramolecular N—H···Cl hydrogen bonds (Table 1) to the nearest chloride ligand. Their best planes exhibit respective dihedral angles of 26.83 (17), 2.03 (10) and 18.83 (14)° to the planes containing their coordinating nitrogen atoms, Rh1 and the acceptor Cl atoms of their N—H···Cl interactions. The molecules are linked into a network by intermolecular N—H···Cl and C—H···Cl hydrogen bonds (Fig. 2).