Organometallics
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(21.0 g, 70.0 mmol) in Et2O (100 mL) was added. The reaction
mixture was stirred at room temperature for 2 h and then refluxed for
1 h. Water-free Et3NHCl (1.08 g, 7.77 mmol) was added to the
reaction mixture and stirred. All solvents were evaporated in vacuo.
The residue was extracted with warm hexane and crystallized at −30
°C to obtain 22.9 g (44.0 mmol, 63%) of 8 as colorless crystals. mp:
173 °C. 1H NMR (400.13 MHz, C6D6, 298 K): δ = 1.06 (d, JHH = 7
3
Hz, 3H, CHMe2), 1.17 (d, JHH = 7 Hz, 3H, CHMe2), 1.20−1.36 (m,
15H, CHMe2; 4H, Cy-CH2), 1.42 (d, 3JHH = 7 Hz, 3H, CHMe2), 1.54
3
(s, 2H, NH2), 2.00−2.13 (m, 4H, Cy-CH2), 3.46 (sept, JHH = 7 Hz,
1H, CHMe2), 3.57 (sept, 3JHH = 7 Hz, 1H, CHMe2), 3.63 (sept, 3JHH
=
7 Hz, 1H, CHMe2), 3.88 (sept, 3JHH = 7 Hz, 1H, CHMe2), 6.79−7.24
(m, 11H, arom. H). 13C{1H} NMR (100.61 MHz, C6D6, 298 K): δ =
21.4 (CHMe2), 23.0 (CHMe2), 23.4 (CHMe2), 23.7 (Cy-CH2), 24.4
(CHMe2), 24.6 (Cy-CH2), 24.8 (CHMe2), 27.2 (CHMe2), 27.6
(CHMe2), 28.4 (CHMe2), 28.5 (CHMe2), 28.8 (CHMe2), 28.9
(CHMe2), 29.0 (CHMe2), 29.3 (Cy-CH2), 31.5 (Cy-CH2), 102.3 (Cy-
CCN), 123.4−146.2 (arom. C), 164.3 (Cy-CN), 166.9 (Ph-CN). IR
(KBr, cm−1): 561 (s), 704 (s), 752 (s), 796 (s), 839 (m), 922 (s),
1052 (s), 1096 (s), 1143 (s), 1174 (s), 1252 (s), 1304 (s), 1360 (s),
1430 (s), 1470 (s), 1543 (s), 2865 (m), 2961 (s), 3021 (w), 3048 (m),
3343 (w), 3430 (w). Anal. Calcd for C37H49GeN3: C, 73.04; H, 8.12;
N, 6.91. Found: C, 72.72; H, 8.10; N, 6.83.
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148−150 °C. H NMR (400.13 MHz, CDCl3, 298 K): δ = 1.17 (d,
3JHH = 7 Hz, 6H, CHMe2), 1.22 (d, 3JHH = 7 Hz, 6H, CHMe2), 1.25 (d,
3
3JHH = 7 Hz, 6H, CHMe2), 1.34 (d, JHH = 7 Hz, 6H, CHMe2), 1.64
(m, 4H, Cy-CH2), 1.87 (s, 1H, NH), 2.17 (m, 4H, Cy-CH2), 3.35 (m,
4H, CHMe2), 6.96 (s, 3H, arom. H), 7.15−7.27 (m, 8H, arom. H).
13C{1H} NMR (100.61 MHz, CDCl3, 298 K): δ = 21.8 (Cy-CH2),
22.1 (CHMe2), 23.6 (CHMe2), 23.8 (Cy-CH2), 24.7 (CHMe2), 25.6
(CHMe2), 28.0 (CHMe2), 28.2 (CHMe2), 28.5 (Cy-CH2), 28.6 (Cy-
CH2), 97.7 (Cy-CCN), 122.2−144.1 (arom. C), 160.0 (Cy-CN), 165.8
(Ph-CN). Anal. Calcd for C37H48N2: C, 85.33; H, 9.29; N, 5.38.
Found: C, 85.18; H, 9.27; N, 5.47.
Compound 4. A diluted solution of H2O in THF (1.79 mL, 1.00
mmol, 0.56 M) was dropped into a solution of 2 (591 mg, 1.00 mmol)
in toluene (10 mL) at −30 °C. The solution turned to a yellow color
and was stirred for 6 h at ambient temperature. The solvents were
removed and the residue redissolved in hexane (40 mL). The
concentrated solution was stored at 0 °C, yielding 4 as yellow crystals
Compound 1. n-Butyllithium (8.81 mL, 14.1 mmol, 1.6 M) was
added to a solution of 8 (7.20 g, 13.8 mmol) in 80 mL of Et2O at −78
°C. The solution was allowed to slowly warm to room temperature
and stirred for 4 h. GeCl2·dioxane (3.30 g, 14.2 mmol) was added to
the reaction solution at −78 °C. The resulting suspension was stirred
overnight at room temperature. Volatiles were removed under reduced
pressure, and the residue was extracted with warm toluene two times.
The filtrate was concentrated and stored at −30 °C, yielding 1 as
yellow crystals (7.10 g, 11.3 mmol, 82%). mp: 203 °C. 1H NMR
1
(0.580 g, 0.95 mmol, 95%). mp: 188 °C. H NMR (400.13 MHz,
C6D6, 298 K): δ = 1.11 (d, 3JHH = 7 Hz, 3H, CHMe2), 1.16 (d, 3JHH
=
7 Hz, 3H, CHMe2), 1.19−1.36 (m, 15H, CHMe2; 4H, Cy-CH2), 1.39
3
(d, JHH = 7 Hz, 3H, CHMe2), 1.66 (s, 1H, OH), 1.95−2.21 (m, 4H,
3
(400.13 MHz, C6D6, 298 K): δ = 0.97 (d, JHH = 7 Hz, 3H, CHMe2),
3
3
Cy-CH2), 3.35 (sept, JHH = 7 Hz, 1H, CHMe2), 3.46 (sept, JHH = 7
1.07 (d, 3JHH = 7 Hz, 3H, CHMe2), 1.16 (d, 3JHH = 7 Hz, 3H, CHMe2),
1.21−1.27 (m, 9H, CHMe2), 1.28−1.39 (m, 4H, Cy-CH2), 1.44 (d,
3JHH = 7 Hz, 3H, CHMe2), 1.55 (d, 3JHH = 7 Hz, 3H, CHMe2), 2.03−
3
Hz, 1H, CHMe2), 3.84 (sept, JHH = 7 Hz, 1H, CHMe2), 3.97 (sept,
3JHH = 7 Hz, 1H, CHMe2), 6.75−7.26 (m, 11H, arom. H). 13C{1H}
NMR (100.61 MHz, C6D6, 298 K): δ = 21.3 (CHMe2), 22.9
(CHMe2), 23.3 (CHMe2), 23.4 (Cy-CH2), 24.3 (CHMe2), 24.6 (Cy-
CH2), 24.7 (CHMe2), 26.9 (CHMe2), 27.6 (CHMe2), 28.1 (CHMe2),
28.3 (CHMe2), 28.8 (CHMe2), 28.9 (CHMe2), 29.0 (CHMe2), 29.1
(Cy-CH2), 31.4 (Cy-CH2), 102.8 (Cy-CCN), 123.3−146.4 (arom. C),
164.7 (Cy-CN), 166.6 (Ph-CN). IR (KBr, cm−1): ν = 561 (s), 713 (s),
743 (s), 770 (s), 791 (s), 839 (s), 926 (m), 1056 (m), 1104 (s), 1148
(s), 1170 (s), 1257 (s), 1313 (s), 1339 (s), 1365 (s), 1430 (s), 1470
(s), 1539 (s), 2861 (s), 2961 (s), 3018 (w), 3057 (m), 3643 (m). Anal.
Calcd for C37H48GeN2O: C, 72.92; H, 7.94; N, 4.60. Found: C, 73.00;
H, 7.86; N, 4.64.
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2.27 (m, 4H, Cy-CH2), 3.17 (sept, JHH = 7 Hz, 1H, CHMe2), 3.27
3
3
(sept, JHH = 7 Hz, 1H, CHMe2), 3.94 (sept, JHH = 7 Hz, 1H,
3
CHMe2), 4.17 (sept, JHH = 7 Hz, 1H, CHMe2), 6.80−7.39 (m, 11H,
arom. H). 13C{1H} NMR (100.61 MHz, C6D6, 298 K): δ = 21.3
(CHMe2), 22.6 (CHMe2), 23.1 (Cy-CH2), 23.9 (CHMe2), 24.5
(CHMe2), 24.6 (Cy-CH2), 24.9 (CHMe2), 27.4 (CHMe2), 27.7
(CHMe2), 28.4 (CHMe2), 28.6 (CHMe2), 28.9 (CHMe2), 29.1
(CHMe2), 29.3 (CHMe2), 29.5 (Cy-CH2), 31.5 (Cy-CH2), 108.9 (Cy-
CCN), 123.4−147.6 (arom. C), 165.1 (Cy-CN), 168.8 (Ph-CN). Anal.
Calcd for C37H47ClGeN2: C, 70.78; H, 7.54; N, 4.46. Found: C, 70.73;
H, 7.62; N, 4.57.
Compound 2. Germylene chloride 1 (3.00 g, 4.79 mmol) and 1,3-
bis-tert-butylimidazol-2-ylidene (0.91 g, 5.02 mmol) were dissolved in
toluene (25 mL) at room temperature and stirred for 48 h, resulting in
a white precipitate of the corresponding NHC·HCl salt. The color of
the solution changed from yellow to brown-red. The solvent was
removed under reduced pressure and the residue extracted with warm
hexane two times. The combined filtrate was concentrated and stored
at −30 °C, yielding 2 as red crystals (2.20 g, 3.73 mmol, 78%). mp:
167−168 °C. 1H NMR (400.13 MHz, C6D6, 298 K): δ = 1.15 (d, 3JHH
= 7 Hz, 6H, CHMe2), 1.26 (d, 3JHH = 7 Hz, 6H, CHMe2), 1.35 (d, 3JHH
= 7 Hz, 12H, CHMe2), 1.55 (m, 2H, Cy-CH2), 2.04 (m, 2H, Cy-CH2),
ASSOCIATED CONTENT
* Supporting Information
Full details of the crystal structure determinations for 1−4
(CIF) are available. This material is available free of charge via
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AUTHOR INFORMATION
Corresponding Author
*Phone: +49(0)30-314-22265. Fax: +49(0)30-314-29732. E-
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3
2.21 (m, 2H, Cy-CH2), 3.69 (sept, JHH = 7 Hz, 2H, CHMe2), 3.80
(sept, 3JHH = 7 Hz, 2H, CHMe2), 4.15 (t, 3JHH = 4.4 Hz, 1H, CCH),
6.75−7.25 (m, 11H, arom. H). 13C{1H} NMR (100.61 MHz, C6D6,
298 K): δ = 22.6 (CHMe2), 23.4 (Cy-CH2), 24.7 (CHMe2), 25.8 (Cy-
CH2), 25.9 (CHMe2), 27.3 (CHMe2), 28.3 (CHMe2), 28.4 (CHMe2),
31.5 (Cy-CH2), 98.7 (Cy-CH), 111.7 (Cy-CCN), 123.6−143.1 (arom.
C), 147.3, 147.4 (Cy-CN, Ph-CN). IR (KBr, cm−1): 704 (s), 787 (s),
939 (m), 1104 (s), 1135 (s), 1204 (s), 1248 (s), 1296 (s), 1322 (s),
1365 (s), 1439 (s), 1461 (s), 1535 (m), 1600 (s), 2822 (m), 2865 (s),
2922 (s), 2957 (w), 3022 (w), 3061 (m). Anal. Calcd for C37H46GeN2:
C, 75.14; H, 7.84; N, 4.74. Found: C, 74.95; H, 8.00; N, 4.84.
Compound 3. A red solution of 2 (591 mg, 1.00 mmol) in
toluene (15 mL) was exposed to dry ammonia gas for 10 min at room
temperature. The solution turned to a yellow color and was stirred for
6 h at ambient temperature. The solvent was removed and the residue
redissolved in hexane (40 mL). The concentrated solution was stored
at 0 °C, yielding 3 as yellow crystals (0.560 g, 0.92 mmol, 92%). mp:
ACKNOWLEDGMENTS
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Financial support from the Deutsche Forchungsgemeinschaft
(DR 226/17-2) and the Alexander von Humboldt Foundation
(Sofja Kovalevskaja Programme for S.I.) is gratefully acknowl-
edged.
REFERENCES
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dx.doi.org/10.1021/om200970s | Organometallics 2011, 30, 6490−6494