Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803018415/cv6225sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803018415/cv6225Isup2.hkl |
CCDC reference: 209188
Key indicators
- Single-crystal X-ray study
- T = 173 K
- Mean (C-C) = 0.003 Å
- R factor = 0.027
- wR factor = 0.059
- Data-to-parameter ratio = 28.4
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT301_ALERT_3_C Main Residue Disorder ....................... 6.00 Perc. PLAT764_ALERT_4_C Overcomplete CIF Bond list Detected (Rep/Expd) 1.11 Ratio
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 2 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion
A mixture of 1.3-butadiene (0.5 mmol), (tBu3SiGeCl)3 (0.12 mmol), (I), and C6D6 (0.6 ml) was photolysed for one week in a sealed NMR tube. The NMR (1H, 13C and 29Si) spectra showed only the signals from (II) and (III), and thus indicated the formation of the cycloadducts (II) and (III) in quantitative yield. Cycloadducts (II) and (III) were separated by HPLC using hexane as eluent (stationary phase; Macherey-Nagel nucleosil 50 Å, 5 mm), and showed peaks with retention times of 17.18 min for (II) and 20.07 min for (III). X-ray quality crystals of (II) were grown from a benzene solution at ambient temperature. NMR data for (I), (II) and (III) are listed in Table 2.
The two central atoms of the butenyl chain are disorderd over two sites. Therefore, they were refined with site occupancy factors of 0.5. H atoms were refined with fixed individual displacement parameters [Uiso(H) = 1.2 Ueq(C) or Uiso(H) = 1.5 Ueq(Cmethyl)], using a riding model with methyl C—H = 0.98, methylene C—H = 0.99 and C(sp2)-H = 0.95 Å.
Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 1991); software used to prepare material for publication: SHELXL97.
[Ge2Cl2(C4H6)(C12H27Si)2] | F(000) = 1416 |
Mr = 669.02 | Dx = 1.297 Mg m−3 |
Orthorhombic, Pbcn | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2n 2ab | Cell parameters from 25280 reflections |
a = 25.236 (1) Å | θ = 2.6–29.2° |
b = 9.6427 (5) Å | µ = 2.00 mm−1 |
c = 14.0761 (6) Å | T = 173 K |
V = 3425.3 (3) Å3 | Plate, colourless |
Z = 4 | 0.17 × 0.14 × 0.08 mm |
STOE IPDS II two-circle diffractometer | 4663 independent reflections |
Radiation source: fine-focus sealed tube | 3368 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.061 |
ω scans | θmax = 29.3°, θmin = 2.7° |
Absorption correction: multi-scan (MULABS; Spek, 1990; Blessing, 1995) | h = −34→34 |
Tmin = 0.728, Tmax = 0.857 | k = −13→13 |
47335 measured reflections | l = −19→19 |
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)] = 0.027 | H-atom parameters constrained |
wR(F2) = 0.059 | w = 1/[σ2(Fo2) + (0.0338P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.87 | (Δ/σ)max = 0.002 |
4663 reflections | Δρmax = 0.60 e Å−3 |
164 parameters | Δρmin = −0.50 e Å−3 |
0 restraints | Extinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.00146 (12) |
[Ge2Cl2(C4H6)(C12H27Si)2] | V = 3425.3 (3) Å3 |
Mr = 669.02 | Z = 4 |
Orthorhombic, Pbcn | Mo Kα radiation |
a = 25.236 (1) Å | µ = 2.00 mm−1 |
b = 9.6427 (5) Å | T = 173 K |
c = 14.0761 (6) Å | 0.17 × 0.14 × 0.08 mm |
STOE IPDS II two-circle diffractometer | 4663 independent reflections |
Absorption correction: multi-scan (MULABS; Spek, 1990; Blessing, 1995) | 3368 reflections with I > 2σ(I) |
Tmin = 0.728, Tmax = 0.857 | Rint = 0.061 |
47335 measured reflections |
R[F2 > 2σ(F2)] = 0.027 | 0 restraints |
wR(F2) = 0.059 | H-atom parameters constrained |
S = 0.87 | Δρmax = 0.60 e Å−3 |
4663 reflections | Δρmin = −0.50 e Å−3 |
164 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 | Occ. (<1) | |
Ge1 | 0.452566 (7) | 0.836245 (18) | 0.224503 (13) | 0.02088 (5) | |
Cl1 | 0.455539 (19) | 0.78760 (5) | 0.07034 (3) | 0.03174 (10) | |
Si1 | 0.374802 (18) | 0.71071 (5) | 0.28568 (4) | 0.02235 (10) | |
C1 | 0.35588 (8) | 0.8074 (2) | 0.40201 (14) | 0.0325 (4) | |
C2 | 0.39647 (7) | 0.5207 (2) | 0.30612 (15) | 0.0309 (4) | |
C3 | 0.31920 (7) | 0.7270 (2) | 0.18986 (14) | 0.0281 (4) | |
C4 | 0.44353 (7) | 1.04284 (18) | 0.21985 (16) | 0.0310 (4) | |
H4A | 0.4059 | 1.0656 | 0.2076 | 0.037* | |
H4B | 0.4650 | 1.0815 | 0.1673 | 0.037* | 0.50 |
H4C | 0.4426 | 1.0802 | 0.2855 | 0.037* | 0.50 |
C11 | 0.31850 (9) | 0.7204 (3) | 0.46493 (17) | 0.0489 (6) | |
H11A | 0.2863 | 0.6981 | 0.4293 | 0.073* | |
H11B | 0.3091 | 0.7735 | 0.5219 | 0.073* | |
H11C | 0.3364 | 0.6344 | 0.4836 | 0.073* | |
C12 | 0.32852 (9) | 0.9478 (3) | 0.38246 (17) | 0.0411 (5) | |
H12A | 0.2962 | 0.9323 | 0.3453 | 0.062* | |
H12B | 0.3526 | 1.0080 | 0.3468 | 0.062* | |
H12C | 0.3194 | 0.9921 | 0.4429 | 0.062* | |
C13 | 0.40592 (9) | 0.8396 (3) | 0.46055 (15) | 0.0406 (5) | |
H13A | 0.4246 | 0.7531 | 0.4748 | 0.061* | |
H13B | 0.3958 | 0.8853 | 0.5200 | 0.061* | |
H13C | 0.4292 | 0.9010 | 0.4240 | 0.061* | |
C21 | 0.34875 (9) | 0.4227 (2) | 0.3222 (2) | 0.0470 (6) | |
H21A | 0.3247 | 0.4283 | 0.2676 | 0.071* | |
H21B | 0.3298 | 0.4505 | 0.3799 | 0.071* | |
H21C | 0.3615 | 0.3272 | 0.3292 | 0.071* | |
C22 | 0.43341 (9) | 0.5090 (2) | 0.39251 (17) | 0.0396 (5) | |
H22A | 0.4640 | 0.5703 | 0.3837 | 0.059* | |
H22B | 0.4457 | 0.4130 | 0.3989 | 0.059* | |
H22C | 0.4142 | 0.5362 | 0.4500 | 0.059* | |
C23 | 0.42755 (8) | 0.4677 (2) | 0.21879 (18) | 0.0369 (4) | |
H23A | 0.4051 | 0.4736 | 0.1622 | 0.055* | |
H23B | 0.4380 | 0.3710 | 0.2292 | 0.055* | |
H23C | 0.4593 | 0.5247 | 0.2097 | 0.055* | |
C31 | 0.32556 (8) | 0.6243 (2) | 0.10687 (16) | 0.0375 (5) | |
H31A | 0.3267 | 0.5294 | 0.1317 | 0.056* | |
H31B | 0.3586 | 0.6443 | 0.0728 | 0.056* | |
H31C | 0.2955 | 0.6339 | 0.0633 | 0.056* | |
C32 | 0.31770 (8) | 0.8730 (2) | 0.14596 (15) | 0.0342 (4) | |
H32A | 0.3137 | 0.9421 | 0.1965 | 0.051* | |
H32B | 0.2877 | 0.8797 | 0.1020 | 0.051* | |
H32C | 0.3508 | 0.8902 | 0.1114 | 0.051* | |
C33 | 0.26451 (7) | 0.6969 (2) | 0.23523 (16) | 0.0380 (5) | |
H33A | 0.2648 | 0.6042 | 0.2638 | 0.057* | |
H33B | 0.2370 | 0.7011 | 0.1862 | 0.057* | |
H33C | 0.2571 | 0.7662 | 0.2844 | 0.057* | |
C41 | 0.46020 (15) | 1.1038 (3) | 0.3088 (3) | 0.0278 (7) | 0.50 |
H41 | 0.4343 | 1.1433 | 0.3496 | 0.033* | 0.50 |
C42 | 0.51068 (15) | 1.1059 (4) | 0.3347 (3) | 0.0298 (8) | 0.50 |
H42 | 0.5189 | 1.1511 | 0.3928 | 0.036* | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ge1 | 0.02350 (8) | 0.01943 (8) | 0.01973 (8) | 0.00000 (7) | 0.00049 (8) | 0.00010 (7) |
Cl1 | 0.0322 (2) | 0.0428 (2) | 0.0203 (2) | −0.0031 (2) | 0.00089 (17) | −0.00326 (17) |
Si1 | 0.0217 (2) | 0.0245 (2) | 0.0209 (2) | 0.00079 (16) | 0.00232 (18) | 0.00053 (19) |
C1 | 0.0299 (9) | 0.0465 (13) | 0.0212 (9) | 0.0085 (8) | 0.0026 (7) | −0.0015 (8) |
C2 | 0.0291 (9) | 0.0239 (9) | 0.0399 (11) | −0.0027 (7) | 0.0051 (8) | 0.0085 (8) |
C3 | 0.0243 (8) | 0.0332 (10) | 0.0270 (9) | 0.0002 (7) | −0.0015 (7) | −0.0020 (8) |
C4 | 0.0351 (10) | 0.0201 (8) | 0.0376 (10) | 0.0030 (6) | −0.0018 (8) | 0.0026 (8) |
C11 | 0.0405 (11) | 0.0757 (18) | 0.0305 (12) | 0.0067 (11) | 0.0138 (9) | 0.0069 (12) |
C12 | 0.0409 (11) | 0.0488 (13) | 0.0338 (11) | 0.0145 (10) | −0.0005 (9) | −0.0139 (10) |
C13 | 0.0404 (11) | 0.0566 (14) | 0.0249 (9) | 0.0105 (10) | −0.0028 (8) | −0.0105 (10) |
C21 | 0.0396 (11) | 0.0319 (11) | 0.0695 (16) | −0.0099 (9) | 0.0043 (11) | 0.0124 (11) |
C22 | 0.0371 (10) | 0.0365 (11) | 0.0451 (13) | 0.0041 (9) | 0.0020 (9) | 0.0146 (10) |
C23 | 0.0354 (10) | 0.0246 (9) | 0.0508 (13) | 0.0020 (7) | 0.0055 (10) | −0.0026 (10) |
C31 | 0.0323 (10) | 0.0450 (13) | 0.0353 (11) | −0.0045 (9) | −0.0032 (8) | −0.0094 (9) |
C32 | 0.0338 (10) | 0.0383 (11) | 0.0303 (10) | 0.0043 (8) | −0.0079 (8) | 0.0029 (8) |
C33 | 0.0240 (8) | 0.0510 (13) | 0.0389 (12) | −0.0032 (8) | −0.0003 (8) | −0.0011 (10) |
C41 | 0.034 (2) | 0.0146 (14) | 0.0349 (19) | 0.0046 (13) | −0.0041 (14) | −0.0060 (13) |
C42 | 0.037 (2) | 0.0186 (16) | 0.034 (2) | 0.0016 (14) | −0.0046 (17) | −0.0082 (15) |
Ge1—C4 | 2.0062 (18) | C13—H13A | 0.9800 |
Ge1—Cl1 | 2.2214 (5) | C13—H13B | 0.9800 |
Ge1—Si1 | 2.4613 (5) | C13—H13C | 0.9800 |
Ge1—Ge1i | 2.4994 (4) | C21—H21A | 0.9800 |
Si1—C2 | 1.934 (2) | C21—H21B | 0.9800 |
Si1—C1 | 1.944 (2) | C21—H21C | 0.9800 |
Si1—C3 | 1.9526 (19) | C22—H22A | 0.9800 |
C1—C13 | 1.539 (3) | C22—H22B | 0.9800 |
C1—C11 | 1.542 (3) | C22—H22C | 0.9800 |
C1—C12 | 1.544 (3) | C23—H23A | 0.9800 |
C2—C22 | 1.536 (3) | C23—H23B | 0.9800 |
C2—C23 | 1.545 (3) | C23—H23C | 0.9800 |
C2—C21 | 1.547 (3) | C31—H31A | 0.9800 |
C3—C32 | 1.537 (3) | C31—H31B | 0.9800 |
C3—C31 | 1.540 (3) | C31—H31C | 0.9800 |
C3—C33 | 1.548 (3) | C32—H32A | 0.9800 |
C4—C41 | 1.445 (4) | C32—H32B | 0.9800 |
C4—C42i | 1.515 (4) | C32—H32C | 0.9800 |
C4—H4A | 0.9898 | C33—H33A | 0.9800 |
C4—H4B | 0.9900 | C33—H33B | 0.9800 |
C4—H4C | 0.9921 | C33—H33C | 0.9800 |
C11—H11A | 0.9800 | C41—C42 | 1.325 (5) |
C11—H11B | 0.9800 | C41—H4C | 0.5975 |
C11—H11C | 0.9800 | C41—H41 | 0.9500 |
C12—H12A | 0.9800 | C42—C4i | 1.515 (4) |
C12—H12B | 0.9800 | C42—H42 | 0.9500 |
C12—H12C | 0.9800 | ||
C4—Ge1—Cl1 | 100.46 (7) | H12A—C12—H12C | 109.5 |
C4—Ge1—Si1 | 114.15 (6) | H12B—C12—H12C | 109.5 |
Cl1—Ge1—Si1 | 105.358 (19) | C1—C13—H13A | 109.5 |
C4—Ge1—Ge1i | 96.79 (5) | C1—C13—H13B | 109.5 |
Cl1—Ge1—Ge1i | 104.371 (16) | H13A—C13—H13B | 109.5 |
Si1—Ge1—Ge1i | 131.548 (15) | C1—C13—H13C | 109.5 |
C2—Si1—C1 | 113.49 (9) | H13A—C13—H13C | 109.5 |
C2—Si1—C3 | 112.48 (9) | H13B—C13—H13C | 109.5 |
C1—Si1—C3 | 111.51 (8) | C2—C21—H21A | 109.5 |
C2—Si1—Ge1 | 107.02 (6) | C2—C21—H21B | 109.5 |
C1—Si1—Ge1 | 104.75 (7) | H21A—C21—H21B | 109.5 |
C3—Si1—Ge1 | 106.96 (6) | C2—C21—H21C | 109.5 |
C13—C1—C11 | 107.71 (18) | H21A—C21—H21C | 109.5 |
C13—C1—C12 | 106.57 (18) | H21B—C21—H21C | 109.5 |
C11—C1—C12 | 107.80 (18) | C2—C22—H22A | 109.5 |
C13—C1—Si1 | 110.26 (13) | C2—C22—H22B | 109.5 |
C11—C1—Si1 | 111.91 (16) | H22A—C22—H22B | 109.5 |
C12—C1—Si1 | 112.34 (14) | C2—C22—H22C | 109.5 |
C22—C2—C23 | 107.30 (17) | H22A—C22—H22C | 109.5 |
C22—C2—C21 | 108.18 (18) | H22B—C22—H22C | 109.5 |
C23—C2—C21 | 108.02 (18) | C2—C23—H23A | 109.5 |
C22—C2—Si1 | 111.02 (15) | C2—C23—H23B | 109.5 |
C23—C2—Si1 | 109.79 (13) | H23A—C23—H23B | 109.5 |
C21—C2—Si1 | 112.35 (14) | C2—C23—H23C | 109.5 |
C32—C3—C31 | 106.64 (17) | H23A—C23—H23C | 109.5 |
C32—C3—C33 | 108.42 (16) | H23B—C23—H23C | 109.5 |
C31—C3—C33 | 106.56 (16) | C3—C31—H31A | 109.5 |
C32—C3—Si1 | 111.66 (13) | C3—C31—H31B | 109.5 |
C31—C3—Si1 | 113.40 (14) | H31A—C31—H31B | 109.5 |
C33—C3—Si1 | 109.91 (14) | C3—C31—H31C | 109.5 |
C41—C4—C42i | 93.1 (2) | H31A—C31—H31C | 109.5 |
C41—C4—Ge1 | 110.02 (18) | H31B—C31—H31C | 109.5 |
C42i—C4—Ge1 | 109.18 (18) | C3—C32—H32A | 109.5 |
C41—C4—H4A | 109.8 | C3—C32—H32B | 109.5 |
C42i—C4—H4A | 123.7 | H32A—C32—H32B | 109.5 |
Ge1—C4—H4A | 109.6 | C3—C32—H32C | 109.5 |
C41—C4—H4B | 109.6 | H32A—C32—H32C | 109.5 |
Ge1—C4—H4B | 109.7 | H32B—C32—H32C | 109.5 |
H4A—C4—H4B | 108.1 | C3—C33—H33A | 109.5 |
C42i—C4—H4C | 110.2 | C3—C33—H33B | 109.5 |
Ge1—C4—H4C | 109.4 | H33A—C33—H33B | 109.5 |
H4A—C4—H4C | 93.3 | C3—C33—H33C | 109.5 |
H4B—C4—H4C | 125.0 | H33A—C33—H33C | 109.5 |
C1—C11—H11A | 109.5 | H33B—C33—H33C | 109.5 |
C1—C11—H11B | 109.5 | C42—C41—C4 | 121.7 (3) |
H11A—C11—H11B | 109.5 | C42—C41—H4C | 150.8 |
C1—C11—H11C | 109.5 | C42—C41—H41 | 119.2 |
H11A—C11—H11C | 109.5 | C4—C41—H41 | 119.2 |
H11B—C11—H11C | 109.5 | H4C—C41—H41 | 88.4 |
C1—C12—H12A | 109.5 | C41—C42—C4i | 126.0 (3) |
C1—C12—H12B | 109.5 | C41—C42—H42 | 117.0 |
H12A—C12—H12B | 109.5 | C4i—C42—H42 | 117.0 |
C1—C12—H12C | 109.5 | ||
C4—Ge1—Si1—C2 | −169.60 (10) | Ge1—Si1—C2—C23 | −46.49 (14) |
Cl1—Ge1—Si1—C2 | 81.16 (7) | C1—Si1—C2—C21 | 78.24 (19) |
Ge1i—Ge1—Si1—C2 | −44.81 (7) | C3—Si1—C2—C21 | −49.53 (19) |
C4—Ge1—Si1—C1 | −48.83 (10) | Ge1—Si1—C2—C21 | −166.71 (15) |
Cl1—Ge1—Si1—C1 | −158.07 (6) | C2—Si1—C3—C32 | −157.43 (13) |
Ge1i—Ge1—Si1—C1 | 75.96 (7) | C1—Si1—C3—C32 | 73.76 (16) |
C4—Ge1—Si1—C3 | 69.64 (9) | Ge1—Si1—C3—C32 | −40.21 (14) |
Cl1—Ge1—Si1—C3 | −39.60 (7) | C2—Si1—C3—C31 | −36.92 (17) |
Ge1i—Ge1—Si1—C3 | −165.57 (6) | C1—Si1—C3—C31 | −165.74 (14) |
C2—Si1—C1—C13 | 72.53 (18) | Ge1—Si1—C3—C31 | 80.29 (15) |
C3—Si1—C1—C13 | −159.20 (15) | C2—Si1—C3—C33 | 82.22 (15) |
Ge1—Si1—C1—C13 | −43.86 (16) | C1—Si1—C3—C33 | −46.60 (17) |
C2—Si1—C1—C11 | −47.33 (17) | Ge1—Si1—C3—C33 | −160.57 (13) |
C3—Si1—C1—C11 | 80.94 (16) | Cl1—Ge1—C4—C41 | −158.52 (19) |
Ge1—Si1—C1—C11 | −163.72 (14) | Si1—Ge1—C4—C41 | 89.27 (19) |
C2—Si1—C1—C12 | −168.76 (14) | Ge1i—Ge1—C4—C41 | −52.5 (2) |
C3—Si1—C1—C12 | −40.49 (18) | Cl1—Ge1—C4—C42i | −57.73 (19) |
Ge1—Si1—C1—C12 | 74.85 (15) | Si1—Ge1—C4—C42i | −169.94 (18) |
C1—Si1—C2—C22 | −43.05 (16) | Ge1i—Ge1—C4—C42i | 48.30 (19) |
C3—Si1—C2—C22 | −170.82 (13) | C42i—C4—C41—C42 | −42.4 (3) |
Ge1—Si1—C2—C22 | 72.00 (14) | Ge1—C4—C41—C42 | 69.3 (4) |
C1—Si1—C2—C23 | −161.53 (13) | C4—C41—C42—C4i | −2.6 (6) |
C3—Si1—C2—C23 | 70.69 (15) |
Symmetry code: (i) −x+1, y, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | [Ge2Cl2(C4H6)(C12H27Si)2] |
Mr | 669.02 |
Crystal system, space group | Orthorhombic, Pbcn |
Temperature (K) | 173 |
a, b, c (Å) | 25.236 (1), 9.6427 (5), 14.0761 (6) |
V (Å3) | 3425.3 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 2.00 |
Crystal size (mm) | 0.17 × 0.14 × 0.08 |
Data collection | |
Diffractometer | STOE IPDS II two-circle diffractometer |
Absorption correction | Multi-scan (MULABS; Spek, 1990; Blessing, 1995) |
Tmin, Tmax | 0.728, 0.857 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 47335, 4663, 3368 |
Rint | 0.061 |
(sin θ/λ)max (Å−1) | 0.688 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.059, 0.87 |
No. of reflections | 4663 |
No. of parameters | 164 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.60, −0.50 |
Computer programs: X-AREA (Stoe & Cie, 2001), X-AREA, SHELXS97 (Sheldrick, 1990), SHELXL97 (Sheldrick, 1997), XP in SHELXTL-Plus (Sheldrick, 1991), SHELXL97.
Ge1—C4 | 2.0062 (18) | Ge1—Ge1i | 2.4994 (4) |
Ge1—Cl1 | 2.2214 (5) | C4—C41 | 1.445 (4) |
Ge1—Si1 | 2.4613 (5) | C41—C42 | 1.325 (5) |
Symmetry code: (i) −x+1, y, −z+1/2. |
1H NMR | 13C NMR | 29Si NMR | |
C6D6 | C6D6 | C6D6 | |
(I) | 1.39 (s, 2SitBu3) | 25.6 (s, CMe3) | 46.5 (s, SitBu3) |
1.40 (s, 2SitBu3) | 26.1 (s, 2CMe3) | 48.4 (s, 2SitBu3) | |
31.7 (s, CMe3) | |||
31.9 (s, 2CMe3) | |||
(II) | 1.31 (s, 2SitBu3) | 25.1 (s, CMe3) | 37.1 (s, 2SitBu3) |
2.53 (s, 2CH2) | 31.5 (s, CMe3) | ||
5.83 (m, 2 ═CH) | 27.8 (s, 2CH2) | ||
125.3 (s, 2 ═CH) | |||
(III) | 1.14 (s, SitBu3) | 23.9 (s, CMe3) | 19.2 (s, SitBu3) |
2.07 (s, 2CH2) | 30.8 (s, CMe3) | ||
6.02 (m, 2 ═CH) | 29.2 (s, 2CH2) | ||
130.4 (s, 2 ═CH) |
Since cyclotrigermanes can be conveniently transformed into germylenes and digermenes, we have become interested in the properties of cis,trans-cyclotrigermane, (tBu3SiGeCl)3. In this context, the photolysis of (tBu3SiGeCl)3 is of particular interest to us. Chlorosupersilylgermylene, tBu3SiGeCl, and trans-1,2-dichloro-1,2-disupersilyldigermene, tBu3SiGeCl═ClGeSitBu3, were formed almost quantitatively by photolysis of cis,trans-cyclotrigermane (tBu3SiGeCl)3 in benzene. The reaction of chlorosupersilylgermylene, tBu3SiGeCl, and trans-1,2-dichloro-1,2-disupersilyldigermene, tBu3SiGeCl═ClGeSitBu3, with 1,3-butadiene gave the [4 + 1] and the [4 + 2] cycloadducts. X-ray quality crystals of the [4 + 2] cycloadduct, the title compound, (II), were obtained from benzene.
Compound (II) is located on a twofold rotation axis running through the Ge—Ge bond. Unfortunately, this imposed symmetry leads to a disordered butenyl chain. Two different orientations of the central C═C double bond can be found. The geometric parameters (Table 1) are comparable with those of trans-(µ2-2,3-dimethylbut-2-ene-1,4-diyl)-dichloro-disupersilyl-digermane (Ichinohe et al., 2000).