Organometallics
Communication
F3C6H2)3]. (c) Padelidakis, V.; Tyrra, W.; Naumann, D. J. Fluorine
Chem. 1999, 99, 9−15 [B(3-FC6H4)3 and B(2,4,6-F3C6H2)3].
(d) Ullrich, M.; Lough, A. J.; Stephan, D. W. J. Am. Chem. Soc.
2009, 131, 52−53 [B(2,3,5,6-F4C6H)3]. (e) Nicasio, J. A.; Steinberg,
fluorination promixal to the boron atom, Lewis acid 5 shows
hardly any difference in Lewis acidity to often-used B(C6F5)3
(1). Moreover, 5 performs equally well in catalytic Si−H bond
activation. With the C-1 and C-3 positions in the naphthalen-2-
yl backbone available for further functionalization, these results
might pave the way for the preparation of chiral boranes with
remotely fluorinated 1,1′-binaphthalene-2,2′-diyl backbones.
́
S.; Ines, B.; Alcarazo, M. Chem.−Eur. J. 2013, 19, 11016−11020
[B(2,4-F2C6H3)3 and B(2,4,5-F3C6H2)3]. (f) Morgan, M. M.; Marwitz,
A. J. V.; Piers, W. E.; Parvez, M. Organometallics 2013, 32, 317−322
[B(2,3,4,5-F4C6H)3]. Biphenyl-substituted analogues of B(C6F5)3:
(g) Chen, Y.-X.; Stern, C. L.; Yang, S.; Marks, T. J. J. Am. Chem. Soc.
1996, 118, 12451−12452. (h) Metz, M. V.; Schwartz, D. J.; Stern, C.
L.; Nickias, P. N.; Marks, T. J. Organometallics 2000, 19, 3332−3337.
ASSOCIATED CONTENT
* Supporting Information
■
S
(6) (a) Mewald, M.; Frohlich, R.; Oestreich, M. Chem.−Eur. J. 2011,
̈
Experimental details, characterization data, NMR spectra, and
crystallographic data. This material is available free of charge via
17, 9406−9414. (b) Mewald, M.; Oestreich, M. Chem.−Eur. J. 2012,
18, 14079−14084.
(7) Liu, Y.; Du, H. J. Am. Chem. Soc. 2013, 135, 6810−6813.
(8) Morrison, D. J.; Piers, W. E.; Parvez, M. Synlett 2004, 2429−
2433.
AUTHOR INFORMATION
Corresponding Author
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(9) Li, L.; Marks, T. J. Organometallics 1998, 17, 3996−4003.
(10) Borane 5 is mentioned in a patent, but no detailed synthesis is
reported: Rodriguez, G.; Rix, F. C.; Ravishankar, P. S.; Kuchta, M. C.
Partially Fluorinated Naphthyl-Based Borates. PCT Int. Appl. WO 03/
051892 A1, 2003.
Notes
The authors declare no competing financial interest.
(11) Coe, P. L.; Pearl, G. M.; Tatlow, J. C. J. Chem. Soc. C 1971,
604−608.
ACKNOWLEDGMENTS
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M.D. thanks the Scientific and Technological Research Council
(12) Yudin, A. K.; Martyn, L.; James, P.; Pandiaraju, S.; Zheng, J.;
Lough, A. Org. Lett. 2000, 2, 41−44.
̈
̇
of Turkey (TUBITAK) for a postdoctoral fellowship (2012−
2013), and M.O. is indebted to the Einstein Foundation
(Berlin) for an endowed professorship.
(13) Murata, M.; Oyama, T.; Watanabe, S.; Masuda, Y. J. Org. Chem.
2000, 65, 164−168.
(14) Iimura, S.; Wu, W. Tetrahedron Lett. 2010, 51, 1353−1355.
(15) Thompson, A. L. S.; Kabalka, G. W.; Akula, M. R.; Huffmann, J.
W. Synthesis 2005, 547−550.
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dx.doi.org/10.1021/om500128a | Organometallics 2014, 33, 1108−1111