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Journal of the American Chemical Society
Erker, G.; Kehr, G.; Bergander, K.; Frohlich, R.; Grimme, S.;
Stephan, D. W. Chem. Commun. 2007, 5072ꢀ5074.
fitted with a pressure valve. The tube was evacuated and reꢀ
1
2
3
4
5
6
7
8
filled with 2 bar of CO2. It was then closed and shaken periodꢀ
ically over 5 min until the redꢀbrown mixture turned bright
yellow. Complex 12a was characterized in situ and showed no
decomposition over several days. The NMR tube was then
heated to 60 °C for 4 hrs under dynamic vacuum. Solvent level
was restored and the mixture was analyzed again, showing a
2/5 mixture of 12a and 8a.
2.
Stephan, D. W.; Erker, G. Angew. Chem. Int. Ed. 2010,
49, 46ꢀ76.
3.
(a) Frustrated Lewis Pair Chemistry I: uncovering and
understanding; Erker, G.; Stephan, D. W., Eds.; Springer, 2013;
Vol. 332; (b) Frustrated Lewis Pair Chemistry II: expanding the
scope; Erker, G.; Stephan, D. W., Eds.; Springer, 2013; Vol. 334;
(c) Stephan, D. W.; Erker, G. Angew. Chem. Int. Ed. 2015, 54,
6400ꢀ6441.
Procedure for catalytic hydrogenation (NMR scale). In an
Argon glovebox, a 0.1 M stock solution of catalyst (typically
0.1 mmol of Zr complex 1a-e and B(C6F5)3 in 1.0 mL C6D5Br)
was prepared and a 0.2 mL aliquot was added to a solution of
CP2Fe (standard ; 9.3 mg, 0.05 mmol) and the substrate (1.0 or
2.0 mmol) in C6D5Br (0.6 mL). The Schlenk vessel was frozen
with liquid nitrogen and was evacuated. After thawing, it was
refilled with 1.5 bar of H2. The reaction mixture was stirred for
the indicated time at room temperature. Product conversion
was estimated by 1H NMR after dilution with C6D5Br (integraꢀ
tion of a suitable signal vs Cp2Fe or remaining starting materiꢀ
al).
9
4.
Fontaine, F.ꢀG.; Courtemanche, M.ꢀA.; Légaré, M.ꢀA.
Chem. Eur. J. 2014, 20, 2990ꢀ2996.
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5.
2581.
6.
Flynn, S. R.; Wass, D. F. ACS Catalysis 2013, 3, 2574ꢀ
(a) Neu, R. C.; Otten, E.; Lough, A.; Stephan, D. W.
Chem. Sci. 2011, 2, 170ꢀ176; (b) Chapman, A. M.; Haddow, M.
F.; Wass, D. F. J. Am. Chem. Soc. 2011, 133, 18463ꢀ18478; (c)
Chapman, A. M.; Haddow, M. F.; Wass, D. F. J. Am. Chem. Soc.
2011, 133, 8826ꢀ8829; (d) Chapman, A. M.; Wass, D. F. Dalton
Trans. 2012, 41, 9067ꢀ9072; (e) Chapman, A. M.; Haddow, M. F.;
Wass, D. F. Eur. J. Inorg. Chem. 2012, 2012, 1546ꢀ1554; (f)
Sgro, M. J.; Stephan, D. W. Angew. Chem. Int. Ed. 2012, 51,
11343ꢀ11345; (g) Sgro, M. J.; Stephan, D. W. Chem. Commun.
2013, 49, 2610ꢀ2612; (h) Kalz, K. F.; Brinkmeier, A.; Dechert, S.;
Mata, R. A.; Meyer, F. J. Am. Chem. Soc. 2014, 136, 16626ꢀ
16634; (i) Xu, X.; Kehr, G.; Daniliuc, C. G.; Erker, G. J. Am.
Chem. Soc. 2013, 135, 6465ꢀ6476; (j) Xu, X.; Kehr, G.; Daniliuc,
C. G.; Erker, G. Organometallics 2013, 32, 7306ꢀ7311; (k) Xu,
X.; Kehr, G.; Daniliuc, C. G.; Erker, G. Angew. Chem. Int. Ed.
2013, 52, 13629ꢀ13632; (l) Fromel, S.; Kehr, G.; Frohlich, R.;
Daniliuc, C. G.; Erker, G. Dalton Trans. 2013, 42, 14531ꢀ14536;
(m) Xu, X.; Kehr, G.; Daniliuc, C. G.; Erker, G. J. Am. Chem.
Soc. 2014, 136, 12431ꢀ12443; (n) Xu, X.; Kehr, G.; Daniliuc, C.
G.; Erker, G. J. Am. Chem. Soc. 2015, 137, 4550ꢀ4557; (o)
Normand, A. T.; Richard, P.; Balan, C.; Daniliuc, C. G.; Kehr, G.;
Erker, G.; Le Gendre, P. Organometallics 2015, 34, 2000ꢀ2011;
(p) Xu, X.; Kehr, G.; Daniliuc, C. G.; Erker, G. Organometallics
2015, 34, 2655ꢀ2661.
Procedure for catalytic hydrogenation of styrene (prepara-
tive scale). In an Argon glovebox, a 0.1 M stock solution of
catalyst (0.1 mmol of Zr complex 1e and B(C6F5)3 in 1 mL
C6D5Br) was prepared and this was added to a solution of
styrene (10 mmol) in C6D5Br (3 mL). The Schlenk vessel was
evacuated and refilled with 1.5 bar of H2. The reaction mixture
was stirred for2 hours at room temperature. Product distribuꢀ
tion was estimated by 1H NMR as previously. The crude reacꢀ
tion mixture was filtered through a plug of silica gel and elutꢀ
ed with CH2Cl2. After evaporation the residue was distilled at
1
60 °C/0.3 mBar and the residue was analyzed by H NMR in
CDCl3 and GCMS, revealing the presence of a 5/1 mixture of
1,4ꢀdiphenylbutane and 1,3ꢀdiphenylbutane (373 mg, 36 %)
with traces of a third product arising from the coupling of
three styrene moieties (Mw = 314).
7.
(a) Podiyanachari, S. K.; Fröhlich, R.; Daniliuc, C. G.;
ASSOCIATED CONTENT
Petersen, J. L.; MückꢀLichtenfeld, C.; Kehr, G.; Erker, G. Angew.
Chem. Int. Ed. 2012, 51, 8830ꢀ8833; (b) Forrest, S. J. K.; Clifton,
J.; Fey, N.; Pringle, P. G.; Sparkes, H. A.; Wass, D. F. Angew.
Chem. Int. Ed. 2015, 54, 2223ꢀ2227.
Details about the experimental procedures, characterization of all
new compounds, and crystal structure data as CIF files. This
material is available free of charge via the Internet at
8.
(a) HeyꢀHawkins, E. Chem. Rev. 1994, 94, 1661ꢀ1717;
(b) Stephan, D. W. Angew. Chem. Int. Ed. 2000, 39, 314ꢀ329; (c)
Waterman, R. Dalton Trans. 2009, 18ꢀ26; (d) Rosenberg, L.
Coord. Chem. Rev. 2012, 256, 606ꢀ626.
AUTHOR INFORMATION
Corresponding Authors
9.
(a) Temme, B.; Erker, G. J. Organomet. Chem. 1995,
*Eꢀmail: erker@uniꢀmuenster.de.
*Eꢀmail: pierre.leꢀgendre@uꢀbourgogne.fr.
488, 177ꢀ182; (b) Harlan, C. J.; Bridgewater, B. M.; Hascall, T.;
Norton, J. R. Organometallics 1999, 18, 3827ꢀ3834.
10.
(a) Fryzuk, M. D.; Mao, S. S. H.; Zaworotko, M. J.;
Notes
MacGillivray, L. R. J. Am. Chem. Soc. 1993, 115, 5336ꢀ5337; (b)
Weng, W.; Yang, L.; Foxman, B. M.; Ozerov, O. V.
Organometallics 2004, 23, 4700ꢀ4705; (c) Kamitani, M.; Pinter,
B.; Chen, C.ꢀH.; Pink, M.; Mindiola, D. J. Angew. Chem. Int. Ed.
2014, 53, 10913ꢀ10915.
The authors declare no competing financial interest.
ACKNOWLEDGEMENTS
Financial support from Agence Nationale de la Recherche and
Deutsche Forschungsgemeinschaft (MENOLEP programme) and
Conseil Régional de Bourgogne (PARI CDEA program) is grateꢀ
fully acknowledged.
11.
12.
For a discussion of the "carbene analogy", see ref. 8d.
(a) Douglass, M. R.; Marks, T. J. J. Am. Chem. Soc.
2000, 122, 1824ꢀ1825; (b) Douglass, M. R.; Stern, C. L.; Marks,
T. J. J. Am. Chem. Soc. 2001, 123, 10221ꢀ10238; (c) Gagné, M.
R.; Marks, T. J. J. Am. Chem. Soc. 1989, 111, 4108ꢀ4109; (d)
Hong, S.; Marks, T. J. Acc. Chem. Res. 2004, 37, 673ꢀ686; (e)
Kawaoka, A. M.; Marks, T. J. J. Am. Chem. Soc. 2004, 126,
REFERENCES
1.
(a) Welch, G. C.; Juan, R. R. S.; Masuda, J. D.;
Stephan, D. W. Science 2006, 314, 1124ꢀ1126; (b) Spies, P.;
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