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Commun., 2008, 4303–4305.
5 (a) J. S. J. McCahill, G. C. Welch and D. W. Stephan, Angew. Chem., Int.
Ed., 2007, 46, 4968–4971; (b) M. Ullrich, K. S. H. Seto, A. J. Lough and
toluene (2 mL) containing allene 8 (33 mg, 0.0883 mmol) at the
same temperature. Subsequently, 4-methylphenyl disulfide
(22 mg, 0.0883 mmol) was added and the resulting mixture was
allowed to reach room temperature overnight. Evaporation of the
solvents afforded an oil that was redissolved in CH2Cl2. After
addition of two drops of HPF6 the mixture was washed with
3 mL of water and the organic phase separated and dried. After
evaporation of the solvents the crude mixture was purified by
column chromatography (SiO2; dichloromethane : pentane 2 : 3)
to afford compound 39 as a yellow solid (42 mg, 93%).
1H NMR (400 MHz, CD2Cl2): δ = 8.48 (br, s, 1H), 7.89 (m,
1H), 7.28 (dd, J = 7.8, 1.2 Hz, 1H), 7.21 (dd, J = 7.8, 1.2 Hz,
1H), 7.06 (d, J = 8.1 Hz, 2H), 6.98 (t, J = 6.4 Hz, 1H), 6.87
(d, J = 8.1 Hz, 2H), 6.78 (t, J = 6.4 Hz, 1H), 5.45 (br, 1H),
4.13–3.99 (m, 4H), 2.15 (s, 3H), 1.10 (t, J = 7.5 Hz, 6H) ppm;
13C NMR (100 MHz, CD2Cl2): δ = 167.1, 161.5 (d, J = 249
Hz), 161.4 (d, J = 249 Hz), 136.7, 134.0, 130.1, 129.8 (d, J = 9
Hz), 127.2 (d, J = 9 Hz), 115.05 (d, J = 22 Hz), 107.7 (d, J = 23
Hz), 106.9 (d, J = 23 Hz), 62.6, 60.2, 20.9, 14.1 ppm; 19F NMR
(282 MHz, CD2Cl2): δ = −111.81, −112.03 ppm; HRMS calcd
for C28H24O4F2SNa+: 517.125556; found: 517.125587.
D.
W.
Stephan,
Chem.
Commun.,
2009,
2335–2337;
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6 (a) G. C. Welch, R. R. S. Juan, J. D. Masuda and D. W. Stephan,
Science, 2006, 314, 1124–1126; (b) For the splitting of dihydrogen using
a single carbon center see: .G. D. Frey, V. Lavallo, B. Donnadieu, W.
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7 (a) P. Spies, S. Schwendermann, S. Lange, G. Kehr, R. Frölich and
G. Erker, Angew. Chem., Int. Ed., 2008, 47, 7543–7546; (b) P. A. Chase,
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(f) T. A. Rokob, A. Hamza and I. Pápai, J. Am. Chem. Soc., 2009, 131,
10701–10710; (g) S. Grimme, H. Kruse, L. Goerigk and G. Erker,
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A. L. Gille, T. M. Gilgert and D. W. Stephan, Inorg. Chem., 2009, 48,
10466–10474.
Compound 40
9 (a) D. Holschumacher, T. Bannenberg, C. G. Hrib, P. G. Jones and
M. Tamm, Angew. Chem., Int. Ed., 2008, 47, 7428–7432; (b) P. A. Chase
and D. W. Stephan, Angew. Chem., Int. Ed., 2008, 47, 7433–7437;
(c) M. Alcarazo, C. Gomez, S. Holle and R. Goddard, Angew.
Chem., Int. Ed., 2010, 49, 5788–5791; for recent reviews on the synthesis
coordination and reactivity of N-heterocyclic carbenes see (d) T. Dröge
and F. Glorious, Angew. Chem., Int. Ed., 2010, 49, 6940–6952;
(e) F. E. Hahn and M. C. Jahnke, Angew. Chem., Int. Ed., 2008, 47,
3122–3172.
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T. Soós, Angew. Chem., Int. Ed., 2010, 49, 6559–6563; for studies target-
ing structural modifications of B(C6F5)3 see (b) Y. X. Chen, C. L. Stern,
S. Yang and T. J. Marks, J. Am. Chem. Soc., 1996, 118, 12451–12452;
(c) Y. X. Chen, M. V. Metz, L. Li, C. L. Stern and T. J. Marks, J. Am.
Chem. Soc., 1998, 120, 6287–6305; (d) L. Li and T. J. Marks, Organome-
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P. N. Nickias and T. J. Marks, Angew. Chem., Int. Ed., 2000, 39, 1312–
1316; (f) L. Li, C. L. Stern and T. J. Marks, Organometallics, 2000, 19,
3332–3337; (g) P. A. Chase, W. E. Piers and B. O. Patrick, J. Am. Chem.
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L. Stern, T. J. Marks and P. N. Nickias, Organometallics, 2002, 21,
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M. Parvaez, W. Clegg and M. R. J. Elsegood, Organometallics, 2006, 25,
349–357; (m) For a recent FLP not based in polyfluorinated boranes see:
F. Bertini, V. Lyaskovskyy, B. J. J. Timmer, F. J. J. Kanter, M. Lutz, A.
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134, 201–204.
It was prepared as described above but starting with carbene 23
(0.034 g, 0.089 mmol) and allene 10 (0.04 g, 0.089 mmol). The
crude was purified by chromatography column on silica gel
(eluent hexane : ethyl acetate 3 : 1) affording compound 40 as a
1
yellow oil (0.028 g, 78%). H NMR (300 MHz, CDCl3): δ =
9.22 (s, 1H), 8.65 (s, 1H), 8.11 (dd, J = 8.0, 1.3 Hz, 1H), 8.01
(dd, J = 8.0, 1.5 Hz, 1H), 7.80 (d, J = 8.1 Hz, 1H), 7.72 (d, J =
8.1 Hz, 1H), 7.28 (d, J = 8.4 Hz, 2H), 6.95 (d, J = 8.3 Hz, 2H),
4.30–4.21 (m, 4H), 3.98 (s, 1H), 3.97 (s, 3H), 3.90 (s, 3H), 2.19
(s, 3H), 1.28 (t, J = 7.4 Hz, 6H) ppm; 13C NMR (150 MHz,
CDCl3): δ = 166.9, 166.7, 166.6, 143.8, 143.7, 143.1, 141.6,
137.9, 133.6, 133.5, 130.4, 130.3, 129.9, 129.8, 129.7, 129.4,
129.3, 126.2, 120.3, 119.6, 62.4, 59.7, 52.3, 52.1, 20.9,
13.9 ppm; IR (neat) ν = 762, 807, 1025, 1098, 1250, 1289,
1439, 1720, 2950 cm−1; HRMS calcd. for C32H30O8SNa+:
597.155363; found: 597.155361.
Acknowledgements
This work has been supported by the Fonds der Chemischen
Industrie and the European Research Council (ERC Starting
Grant agreement no. 277963). We also thank the analytical
departments of our institute for excellent support and Prof. Alois
Fürstner for constant encouragement.
11 (a) B. Inés, S. Holle, R. Goddard and M. Alcarazo, Angew. Chem., Int.
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12 (a) For a comprehensive monography regarding thermal rearrangements
of allenes see: J. E. Baldwin and R. H. Fleming, Fortschr. Chem.
Forsch., 1970, 15, 281–310. See also: (b) O. J. Muscio and T. L. Jacobs,
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Notes and references
1 For some reviews on the chemistry of frustrated Lewis pairs see: (a) D.
W. Stephan and G. Erker, Angew. Chem., Int. Ed., 2010, 49, 46–76;
(b) D. W. Stephan, Org. Biomol. Chem., 2008, 6, 1535–1539.
2 (a) M. A. Dureen and D. W. Stephan, J. Am. Chem. Soc., 2009, 131,
8396–8397; (b) C. Jiang, O. Blacque and H. Berke, Organometallics,
2010, 29, 125–133.
3 (a) S. J. Geier and D. W. Stephan, J. Am. Chem. Soc., 2009, 131, 3476–
3477; (b) G. C. Welch, J. D. Masuda and D. W. Stephan, Inorg. Chem.,
2006, 45, 478–480; (c) B. Birkmann, T. Voss, S. J. Geier, M. Ullrich,
This journal is © The Royal Society of Chemistry 2012
Dalton Trans., 2012, 41, 9073–9082 | 9081