Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270100016176/gd1121sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270100016176/gd1121Isup2.hkl |
CCDC reference: 159999
For related literature, see: Annan et al. (1991); Gade (2000); Gavrushenko et al. (1977); Robertson et al. (1996); Schrock (1997); Skinner et al. (2000).
A solution of Me2N—CH2—CH2—N(H)Me (2.33 g, 22.8 mmol) in CH3CN (10 cm3) was added dropwise to a chilled (273 K) solution of GeCl4 (2.51 g, 11.7 mmol) in CH3CN (10 cm3). After stirring the mixture for 15 min, a solution of Et3N (5.0 g, 49.4 mmol) in CH3CN was added and the resulting solution was warmed at 323 K for 3 h. The solution was filtered whilst still hot, concentrated (ca 50% by volume) and then cooled to ice-cold temperature when colourless needle crystals slowly deposited (yield 0.96 g, 12%). Found: C 34.1, H 9.1, N 15.8%. Calculated for C5H16N2Cl2: C 34.3, H 9.2, N 16.0%.
The hydrogen atoms directly linked to nitrogen atoms were located from electron-density maps, but then restrained under refinement to have equal N—H bond lengths; all other hydrogen atoms were added at calculated positions and refined using a riding model, with C—H 0.98–0.99 Å. Anisotropic displacement parameters were used for all non-H atoms; H atoms were given isotropic displacement parameters equal to 1.2 (or 1.5 for methyl H atoms) times the equivalent isotropic displacement parameter of their parent atoms.
Data collection: SMART (Siemens, 1994a); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT; program(s) used to solve structure: SHELXTL/PC (Siemens, 1994b); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC; software used to prepare material for publication: SHELXTL/PC.
C5H16N22+·2Cl− | F(000) = 752 |
Mr = 350.20 | Dx = 1.264 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 11.1419 (12) Å | Cell parameters from 2396 reflections |
b = 20.2089 (14) Å | θ = 2.0–25.0° |
c = 8.7321 (9) Å | µ = 0.64 mm−1 |
β = 110.644 (4)° | T = 180 K |
V = 1839.9 (3) Å3 | Needle, colourless |
Z = 4 | 0.24 × 0.12 × 0.12 mm |
Siemens SMART CCD area-detector diffractometer | 3236 independent reflections |
Radiation source: normal-focus sealed tube | 1857 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.084 |
Detector resolution: 8.192 pixels mm-1 | θmax = 25.0°, θmin = 2.0° |
ω scans | h = −13→12 |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | k = −24→18 |
Tmin = 0.862, Tmax = 0.928 | l = −10→10 |
8986 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)] = 0.051 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.096 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.98 | w = 1/[σ2(Fo2) + (0.0301P)2] where P = (Fo2 + 2Fc2)/3 |
3236 reflections | (Δ/σ)max < 0.001 |
193 parameters | Δρmax = 0.36 e Å−3 |
15 restraints | Δρmin = −0.30 e Å−3 |
C5H16N22+·2Cl− | V = 1839.9 (3) Å3 |
Mr = 350.20 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.1419 (12) Å | µ = 0.64 mm−1 |
b = 20.2089 (14) Å | T = 180 K |
c = 8.7321 (9) Å | 0.24 × 0.12 × 0.12 mm |
β = 110.644 (4)° |
Siemens SMART CCD area-detector diffractometer | 3236 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1857 reflections with I > 2σ(I) |
Tmin = 0.862, Tmax = 0.928 | Rint = 0.084 |
8986 measured reflections |
R[F2 > 2σ(F2)] = 0.051 | 15 restraints |
wR(F2) = 0.096 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.98 | Δρmax = 0.36 e Å−3 |
3236 reflections | Δρmin = −0.30 e Å−3 |
193 parameters |
Experimental. The temperature of the crystal was controlled using the Oxford Cryosystem Cryostream Cooler (Cosier & Glazer, 1986). Data were collected over a hemisphere of reciprocal space, by a combination of three sets of exposures. Each set had a different ϕ angle for the crystal and each exposure of 10 s covered 0.3° in ω. The crystal to detector distance was 5.01 cm. Coverage of the unique set was over 99% complete to at least 25° in θ. Crystal decay was monitored by repeating the initial frames at the end of the data collection and analyzing the duplicate reflections. |
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 | ||
Cl1 | 0.59151 (9) | 0.26261 (5) | 0.67192 (11) | 0.0285 (3) | |
Cl2 | 0.92284 (9) | 0.76359 (5) | 0.64369 (11) | 0.0307 (3) | |
Cl3 | 0.52652 (9) | 0.46770 (5) | 0.27892 (11) | 0.0294 (3) | |
Cl4 | 0.94462 (9) | 0.50099 (5) | 0.23427 (12) | 0.0336 (3) | |
N1 | 0.7505 (3) | 0.65531 (15) | 0.6997 (4) | 0.0247 (8) | |
H1' | 0.814 (3) | 0.6898 (15) | 0.692 (4) | 0.042 (12)* | |
N2 | 0.7341 (4) | 0.57545 (18) | 0.3004 (4) | 0.0343 (9) | |
H2' | 0.806 (3) | 0.551 (2) | 0.273 (5) | 0.091 (18)* | |
H2" | 0.665 (3) | 0.5423 (18) | 0.305 (5) | 0.078 (16)* | |
C1 | 0.8150 (4) | 0.60572 (17) | 0.8300 (4) | 0.0296 (10) | |
H1A | 0.8532 | 0.6284 | 0.9353 | 0.044* | |
H1B | 0.8824 | 0.5829 | 0.8025 | 0.044* | |
H1C | 0.7518 | 0.5734 | 0.8375 | 0.044* | |
C2 | 0.6524 (4) | 0.69231 (18) | 0.7451 (4) | 0.0303 (10) | |
H2A | 0.6938 | 0.7146 | 0.8502 | 0.045* | |
H2B | 0.5876 | 0.6614 | 0.7544 | 0.045* | |
H2C | 0.6112 | 0.7253 | 0.6605 | 0.045* | |
C3 | 0.6920 (4) | 0.62505 (18) | 0.5344 (4) | 0.0274 (10) | |
H3A | 0.6321 | 0.6570 | 0.4600 | 0.033* | |
H3B | 0.6423 | 0.5854 | 0.5420 | 0.033* | |
C4 | 0.7942 (4) | 0.6055 (2) | 0.4639 (5) | 0.0345 (11) | |
H4A | 0.8437 | 0.6451 | 0.4555 | 0.041* | |
H4B | 0.8542 | 0.5734 | 0.5380 | 0.041* | |
C5 | 0.6694 (4) | 0.62208 (19) | 0.1668 (4) | 0.0362 (11) | |
H5A | 0.6289 | 0.5974 | 0.0649 | 0.054* | |
H5B | 0.7326 | 0.6530 | 0.1529 | 0.054* | |
H5C | 0.6038 | 0.6468 | 0.1937 | 0.054* | |
N3 | 0.7629 (3) | 0.35894 (16) | 0.9303 (4) | 0.0257 (8) | |
H3' | 0.707 (3) | 0.3270 (15) | 0.846 (4) | 0.056 (14)* | |
N4 | 0.7176 (3) | 0.37839 (16) | 0.5438 (4) | 0.0291 (9) | |
H4' | 0.650 (3) | 0.3995 (16) | 0.443 (3) | 0.045 (12)* | |
H4" | 0.674 (3) | 0.3391 (14) | 0.576 (4) | 0.058 (14)* | |
C6 | 0.6761 (4) | 0.39872 (19) | 0.9900 (5) | 0.0358 (11) | |
H6A | 0.7269 | 0.4295 | 1.0746 | 0.054* | |
H6B | 0.6278 | 0.3692 | 1.0360 | 0.054* | |
H6C | 0.6162 | 0.4237 | 0.8986 | 0.054* | |
C7 | 0.8566 (4) | 0.32263 (19) | 1.0698 (4) | 0.0330 (11) | |
H7A | 0.9118 | 0.2952 | 1.0297 | 0.050* | |
H7B | 0.8103 | 0.2943 | 1.1215 | 0.050* | |
H7C | 0.9093 | 0.3544 | 1.1502 | 0.050* | |
C8 | 0.8329 (4) | 0.39977 (18) | 0.8457 (4) | 0.0286 (10) | |
H8A | 0.9012 | 0.3723 | 0.8302 | 0.034* | |
H8B | 0.8749 | 0.4372 | 0.9179 | 0.034* | |
C9 | 0.7495 (4) | 0.42721 (18) | 0.6810 (4) | 0.0290 (10) | |
H9A | 0.6686 | 0.4438 | 0.6898 | 0.035* | |
H9B | 0.7941 | 0.4654 | 0.6540 | 0.035* | |
C10 | 0.8263 (4) | 0.3590 (2) | 0.4933 (4) | 0.0396 (12) | |
H10D | 0.7962 | 0.3278 | 0.4018 | 0.059* | |
H10E | 0.8931 | 0.3380 | 0.5856 | 0.059* | |
H10F | 0.8614 | 0.3984 | 0.4590 | 0.059* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0278 (6) | 0.0266 (6) | 0.0309 (6) | −0.0043 (5) | 0.0100 (5) | −0.0002 (5) |
Cl2 | 0.0257 (6) | 0.0295 (6) | 0.0331 (6) | −0.0032 (5) | 0.0057 (5) | 0.0129 (5) |
Cl3 | 0.0263 (6) | 0.0248 (6) | 0.0336 (6) | 0.0001 (5) | 0.0063 (5) | 0.0064 (5) |
Cl4 | 0.0267 (6) | 0.0329 (6) | 0.0429 (6) | 0.0019 (5) | 0.0142 (5) | −0.0090 (5) |
N1 | 0.024 (2) | 0.022 (2) | 0.028 (2) | −0.0019 (16) | 0.0105 (16) | −0.0033 (17) |
N2 | 0.034 (2) | 0.036 (2) | 0.035 (2) | 0.001 (2) | 0.0155 (19) | −0.0060 (19) |
C1 | 0.034 (3) | 0.021 (2) | 0.031 (2) | 0.002 (2) | 0.008 (2) | 0.003 (2) |
C2 | 0.032 (3) | 0.027 (2) | 0.034 (2) | 0.005 (2) | 0.015 (2) | −0.002 (2) |
C3 | 0.023 (2) | 0.034 (3) | 0.025 (2) | 0.0011 (19) | 0.008 (2) | −0.008 (2) |
C4 | 0.027 (3) | 0.041 (3) | 0.034 (3) | 0.002 (2) | 0.008 (2) | −0.009 (2) |
C5 | 0.040 (3) | 0.038 (3) | 0.033 (3) | −0.001 (2) | 0.016 (2) | 0.004 (2) |
N3 | 0.029 (2) | 0.026 (2) | 0.0182 (19) | 0.0029 (17) | 0.0033 (17) | −0.0007 (17) |
N4 | 0.031 (2) | 0.028 (2) | 0.027 (2) | −0.0012 (17) | 0.0083 (18) | 0.0049 (18) |
C6 | 0.032 (3) | 0.035 (3) | 0.044 (3) | 0.008 (2) | 0.019 (2) | 0.002 (2) |
C7 | 0.034 (3) | 0.034 (3) | 0.027 (2) | 0.006 (2) | 0.006 (2) | 0.011 (2) |
C8 | 0.033 (3) | 0.026 (3) | 0.028 (2) | −0.003 (2) | 0.013 (2) | 0.004 (2) |
C9 | 0.034 (3) | 0.019 (2) | 0.031 (3) | −0.001 (2) | 0.008 (2) | 0.002 (2) |
C10 | 0.047 (3) | 0.041 (3) | 0.034 (3) | 0.003 (2) | 0.019 (2) | 0.003 (2) |
N1—C2 | 1.489 (5) | N3—C6 | 1.486 (5) |
N1—C3 | 1.489 (4) | N3—C7 | 1.488 (4) |
N1—C1 | 1.496 (4) | N3—C8 | 1.497 (4) |
N1—H1' | 1.02 (2) | N3—H3' | 1.01 (2) |
N2—C5 | 1.475 (5) | N4—C10 | 1.480 (5) |
N2—C4 | 1.477 (5) | N4—C9 | 1.495 (4) |
N2—H2' | 1.04 (2) | N4—H4' | 1.03 (2) |
N2—H2" | 1.03 (2) | N4—H4" | 1.02 (2) |
C1—H1A | 0.9800 | C6—H6A | 0.9800 |
C1—H1B | 0.9800 | C6—H6B | 0.9800 |
C1—H1C | 0.9800 | C6—H6C | 0.9800 |
C2—H2A | 0.9800 | C7—H7A | 0.9800 |
C2—H2B | 0.9800 | C7—H7B | 0.9800 |
C2—H2C | 0.9800 | C7—H7C | 0.9800 |
C3—C4 | 1.525 (5) | C8—C9 | 1.515 (5) |
C3—H3A | 0.9900 | C8—H8A | 0.9900 |
C3—H3B | 0.9900 | C8—H8B | 0.9900 |
C4—H4A | 0.9900 | C9—H9A | 0.9900 |
C4—H4B | 0.9900 | C9—H9B | 0.9900 |
C5—H5A | 0.9800 | C10—H10D | 0.9800 |
C5—H5B | 0.9800 | C10—H10E | 0.9800 |
C5—H5C | 0.9800 | C10—H10F | 0.9800 |
C2—N1—C3 | 110.7 (3) | C6—N3—C7 | 109.6 (3) |
C2—N1—C1 | 109.6 (3) | C6—N3—C8 | 113.0 (3) |
C3—N1—C1 | 113.0 (3) | C7—N3—C8 | 109.8 (3) |
C2—N1—H1' | 106 (2) | C6—N3—H3' | 107 (2) |
C3—N1—H1' | 107 (2) | C7—N3—H3' | 111 (2) |
C1—N1—H1' | 110 (2) | C8—N3—H3' | 107 (2) |
C5—N2—C4 | 115.5 (3) | C10—N4—C9 | 115.2 (3) |
C5—N2—H2' | 109 (2) | C10—N4—H4' | 107 (2) |
C4—N2—H2' | 107 (3) | C9—N4—H4' | 108 (2) |
C5—N2—H2" | 106 (2) | C10—N4—H4" | 114 (2) |
C4—N2—H2" | 109 (2) | C9—N4—H4" | 107 (2) |
H2'—N2—H2" | 111 (4) | H4'—N4—H4" | 106 (3) |
N1—C1—H1A | 109.5 | N3—C6—H6A | 109.5 |
N1—C1—H1B | 109.5 | N3—C6—H6B | 109.5 |
H1A—C1—H1B | 109.5 | H6A—C6—H6B | 109.5 |
N1—C1—H1C | 109.5 | N3—C6—H6C | 109.5 |
H1A—C1—H1C | 109.5 | H6A—C6—H6C | 109.5 |
H1B—C1—H1C | 109.5 | H6B—C6—H6C | 109.5 |
N1—C2—H2A | 109.5 | N3—C7—H7A | 109.5 |
N1—C2—H2B | 109.5 | N3—C7—H7B | 109.5 |
H2A—C2—H2B | 109.5 | H7A—C7—H7B | 109.5 |
N1—C2—H2C | 109.5 | N3—C7—H7C | 109.5 |
H2A—C2—H2C | 109.5 | H7A—C7—H7C | 109.5 |
H2B—C2—H2C | 109.5 | H7B—C7—H7C | 109.5 |
N1—C3—C4 | 111.3 (3) | N3—C8—C9 | 114.7 (3) |
N1—C3—H3A | 109.4 | N3—C8—H8A | 108.6 |
C4—C3—H3A | 109.4 | C9—C8—H8A | 108.6 |
N1—C3—H3B | 109.4 | N3—C8—H8B | 108.6 |
C4—C3—H3B | 109.4 | C9—C8—H8B | 108.6 |
H3A—C3—H3B | 108.0 | H8A—C8—H8B | 107.6 |
N2—C4—C3 | 110.4 (3) | N4—C9—C8 | 114.3 (3) |
N2—C4—H4A | 109.6 | N4—C9—H9A | 108.7 |
C3—C4—H4A | 109.6 | C8—C9—H9A | 108.7 |
N2—C4—H4B | 109.6 | N4—C9—H9B | 108.7 |
C3—C4—H4B | 109.6 | C8—C9—H9B | 108.7 |
H4A—C4—H4B | 108.1 | H9A—C9—H9B | 107.6 |
N2—C5—H5A | 109.5 | N4—C10—H10D | 109.5 |
N2—C5—H5B | 109.5 | N4—C10—H10E | 109.5 |
H5A—C5—H5B | 109.5 | H10D—C10—H10E | 109.5 |
N2—C5—H5C | 109.5 | N4—C10—H10F | 109.5 |
H5A—C5—H5C | 109.5 | H10D—C10—H10F | 109.5 |
H5B—C5—H5C | 109.5 | H10E—C10—H10F | 109.5 |
C2—N1—C3—C4 | 162.7 (3) | C6—N3—C8—C9 | −70.0 (4) |
C1—N1—C3—C4 | −74.0 (4) | C7—N3—C8—C9 | 167.3 (3) |
C5—N2—C4—C3 | 74.7 (4) | C10—N4—C9—C8 | −70.1 (4) |
N1—C3—C4—N2 | 179.9 (3) | N3—C8—C9—N4 | −78.9 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1′···Cl2 | 1.02 (2) | 2.05 (2) | 3.062 (3) | 171 (3) |
N2—H2′···Cl4 | 1.04 (2) | 1.97 (2) | 3.009 (4) | 176 (4) |
N2—H2"···Cl3 | 1.03 (2) | 2.11 (2) | 3.134 (4) | 171 (4) |
N3—H3′···Cl1 | 1.01 (2) | 2.07 (2) | 3.080 (3) | 179 (3) |
N4—H4′···Cl3 | 1.03 (2) | 2.11 (2) | 3.110 (3) | 163 (3) |
N4—H4"···Cl1 | 1.02 (2) | 2.11 (2) | 3.132 (3) | 173 (3) |
Experimental details
Crystal data | |
Chemical formula | C5H16N22+·2Cl− |
Mr | 350.20 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 180 |
a, b, c (Å) | 11.1419 (12), 20.2089 (14), 8.7321 (9) |
β (°) | 110.644 (4) |
V (Å3) | 1839.9 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.64 |
Crystal size (mm) | 0.24 × 0.12 × 0.12 |
Data collection | |
Diffractometer | Siemens SMART CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.862, 0.928 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8986, 3236, 1857 |
Rint | 0.084 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.051, 0.096, 0.98 |
No. of reflections | 3236 |
No. of parameters | 193 |
No. of restraints | 15 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.36, −0.30 |
Computer programs: SMART (Siemens, 1994a), SAINT (Siemens, 1995), SAINT, SHELXTL/PC (Siemens, 1994b), SHELXL97 (Sheldrick, 1997), SHELXTL/PC.
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1'···Cl2 | 1.02 (2) | 2.05 (2) | 3.062 (3) | 171 (3) |
N2—H2'···Cl4 | 1.04 (2) | 1.97 (2) | 3.009 (4) | 176 (4) |
N2—H2"···Cl3 | 1.03 (2) | 2.11 (2) | 3.134 (4) | 171 (4) |
N3—H3'···Cl1 | 1.01 (2) | 2.07 (2) | 3.080 (3) | 179 (3) |
N4—H4'···Cl3 | 1.03 (2) | 2.11 (2) | 3.110 (3) | 163 (3) |
N4—H4"···Cl1 | 1.02 (2) | 2.11 (2) | 3.132 (3) | 173 (3) |
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The use of polydentate N-donor ligands to supplant the classic cyclopentadienyl (C5H5) ligand in the development of new catalytic metal complexes (p-block, early d-block, f-block) is of great topical interest (e.g. Schrock, 1997; Gade, 2000; Skinner et al., 2000). In the search for a potential catalyst system based on [Ge(IV)—N]x, we have studied the reaction system GeCl4/Me2N—CH2—CH2—N(H)Me/Et3N/CH3CN. The title compound, (I), was obtained as a side-product (12% yield based on the parent amine) as colourless needle crystals. \sch
In gross terms both of the N centres of the parent amine ligand have been protonated with limited hydrolysis of the Ge—Cl bond(s) (from traces of water impurities) as the most likely source of the acid (HCl).
The asymmetric unit for the title compound is illustrated in Fig. 1. A l l bond lengths and angles are largely unremarkable. The two cations in the asymmetric unit differ in that one has a trans conformation, whilst the other approximates to a gauche arrangement (see torsion angles in Table 1). These differences have a dramatic effect upon the hydrogen-bonding interactions within the lattice. The cation with the gauche conformation is able to mimic a bidentate ligand by forming two hydrogen bonds from opposite ends of the molecule to a single chloride ion (i.e. to Cl1); a third hydrogen bond links this cation to a second chloride ion. In contrast, the 'trans' cation is only able to hydrogen bond to three separate chloride ions (see Fig. 1). All of these hydrogen-bonding interactions are conventional two-centre (i.e. linear) interactions with N—H.·Cl angles (Table 2) ranging from 163 to 179°. The hydrogen bonding described above does not extend in a polymeric sense throughout the lattice, but is confined to small clusters corresponding to the asymmetric unit. The most important lattice forces are undoubtedly ionic interactions.
The cationic component of this structure does not appear to have been the subject of any previous X-ray investigation. The closest comparisons involve the ethylenediammonium (as the citrate; Gavrushenko et al., 1977) and N,N,N',N'-tetramethylethylenediammonium cations. The ethylendiammonium unit was observed to have a gauche conformation [with a torsion angle of 71.4 (2)°], whilst the two reported structures (with Br-, Annan et al., 1991; with I3-, Robertson et al., 1996) involving the N,N,N',N'-tetramethylethylenediammonium ion both have trans conformations. In all of these structures, including the title compound, hydrogen bonding appears to be important in the stabilization of the observed conformations.