2262
E. Lu et al.
LETTER
(4) Brukelman, S. P.; Leach, S. E.; Meakins, G. D.; Tirel, M. D.
J. Chem. Soc., Perkin Trans. 1 1984, 2801.
(5) Martin, S. F.; Limberakis, C. Tetrahedron Lett. 1997, 38,
2617.
BSB-protected aniline 3m with LDA followed by acidic
workup delivered selectively the amide 12 in excellent
yield.
(6) Kim, B. M.; Cho, J. H. Tetrahedron Lett. 1999, 40, 5333.
(7) (a) Djuric, S.; Venit, J.; Magnus, P. Tetrahedron Lett. 1981,
22, 1787. (b) Weisenfeld, R. B.; Miller, M. D. Synth.
Commun. 1986, 16, 809.
(8) Bonar-Law, R. P.; Davis, A. P.; Dorgan, B. J. Tetrahedron
Lett. 1990, 31, 6721.
O
OH
O
1. LDA (2 equiv)
THF, –78 °C
to r.t., 12 h
O
NEt2
NEt2
2. CF3COOH
CH2Cl2, r.t.
NH2
NHBoc
(9) Davis, A. P.; Gallagher, P. J. Tetrahedron Lett. 1995, 36,
3269.
11
80% yield
10
(10) Liu, H.-R.; Gomes, P. T.; Costa, M.; Duarte, M. T.;
Branquinho, R.; Fernandes, A. C.; Chien, J. C. W.; Singh, R.
P.; Marques, M. M. J. Organomet. Chem. 2005, 690, 1314.
(11) (a) Valliant, J. F.; Donovan, A. C. Nucl. Med. Biol. 2008, 35,
741. (b) Kimpe, N. D.; Van T, N. Tetrahedron 2000, 56,
7969.
O
1. LDA (2 equiv)
THF, –78 °C
to r.t., 12 h
O
OH
O
NEt2
Et2N
2. HCl (2 M)
Si
NH2
N
(12) HMPA, elevated temperature, and long reaction times
required to install the ‘benzostabase’ group, see ref. 8. For
elevated temperatures, long reaction times, see:
(a) Zhichkin, P. E.; Krasutsy, S. G.; Beer, C. M.; Rennells,
W. M.; Lee, A. J.; Xiong, J.-M. Synthesis 2011, 1604.
(b) Guggenheim, T. L. Tetrahedron Lett. 1984, 25, 1253.
(13) (a) Stromgaard, K.; Bach, A. Synthesis 2011, 807. (b) For
installation of the stabase group using TMPMgCl·LiCl, see:
Stoll, A. H.; Knochel, P. Org. Lett. 2008, 10, 113. (c) For
installation of stabase using NaH, see: Metobo, S. E.; Xu, J.;
Saunders, O. L.; Butler, T.; Aktoudianakis, E.; Cho, A.;
Kim, A. U. Tetrahedron Lett. 2012, 53, 484.
12
87% yield
Si
3m
Scheme 4 Bimodal translocation of diethylamide using NHBoc and
BSB group
In conclusion, we have described a generally applicable
method for installing the BSB group onto a diverse set of
primary anilines and demonstrated its use in several an-
ionic transformations. Most notably, in the anionic ortho
Snieckus–Fries rearrangement, we have demonstrated for
the first time the complimentary use of both a directed
metalation group and a benzostabase to induce two regio-
selective translocation modes of the diethylamide.
(14) For the synthesis of the TEDI-group precursors, see:
(a) Ishikawa, M.; Sakamoto, H.; Tabuchi, T.
Organometallics 1991, 10, 3173. (b) Wetter, C.; Gierlich, J.;
Knoop, C. A.; Muller, C.; Schulte, T.; Studer, A. Chem. Eur.
J. 2004, 10, 1156.
(15) BSBCl was prepared in one step from the commercially
available silane by the method outlined in ref. 14b.
(16) Elmquist, C. E.; Stover, J. S.; Wang, Z.; Rizzo, C. J. J. Am.
Chem. Soc. 2004, 126, 11189.
(17) (a) Krizan, T.; Martin, J. J. Am. Chem. Soc. 1983, 105, 6155.
(b) Taylor, S.; Lee, D.; Martin, J. J. Org. Chem. 1983, 48,
4156.
Acknowledgment
DFW acknowledges salary support from a Canada Research Chair
Tier 1. This work was supported in part with funding from the
Canadian Institutes of Health Research.
(18) Note: We have synthesized the equivalent stabase adducts of
several of our examples and found the majority of them to be
unstable to aqueous workup.
(19) Krasovsky, A.; Straub, B. F.; Knochel, P. Angew. Chem. Int.
Ed. 2004, 43, 3333.
Supporting Information for this article is available online at
m
o
ti
References and Notes
(20) (a) Snieckus, V. Chem. Rev. 1990, 90, 879. (b) Hartung, C.
G.; Snieckus, V. In Modern Arene Chemistry; Astruc, D.,
Ed.; Wiley-VCH: Weinheim, 2002, 330.
(21) (a) Riggs, C. J.; Singh, K. J.; Yun, M.; Collum, D. B. J. Am.
Chem. Soc. 2008, 130, 13709. (b) Sibi, M. P.; Snieckus, V.
J. Org. Chem. 1983, 48, 1935.
(22) Note: For the anionic ortho Snieckus–Fries rearrangement,
LDA was used in place of LHMDS due to the ability of
LHMDS to affect efficient ortho lithiation.
(23) Seganish, M. W.; DeShong, P. J. Org. Chem. 2004, 69,
6790.
(24) For transformation of the aromatic diethylamide into the
more versatile aldehyde group, see: Zhao, Y.; Snieckus, V.
US 0145060, 2010.
(25) Note: Aniline 1m was synthesized in a fashion analogous to
that of compound 8, see the Supporting Information for the
synthesis of 8, 10, and 3m.
(1) (a) Reetz, M. T.; Drewes, M. W.; Schmitz, A. Angew.
Chem., Int. Ed. Engl. 1987, 26, 1141. (b) Smith, N. D.;
Wohlrab, A. M.; Goodman, M. Org. Lett. 2005, 7, 255.
(2) (a) Wang, Z.; Rizzo, C. J. Org. Lett. 2001, 7, 565.
(b) Macleod, C.; Hartley, R. C.; Hamprecht, D. W. Org. Lett.
2002, 4, 75.
(3) (a) Pratt, R. J.; Massey, D. W.; Pinkerton, F. H.; Thames, S.
F. J. Org. Chem. 1975, 40, 1090. (b) Deshpande, M. N.;
Wehrli, S.; Jawdosiuk, M.; Guy, J. T.; Bennett, D. W.; Cook,
J. M. J. Org. Chem. 1986, 51, 2436. (c) Smith, A. B.; Cui, H.
Org. Lett. 2003, 5, 587. (d) Takagishi, S.; Katsoulos, G.;
Schlosser, M. Synlett 1992, 360. (e) Baston, E.; Maggi, R.;
Fredrich, K.; Schlosser, M. Eur J. Org. Chem. 2001, 3985.
(f) Leroux, F.; Castagnetti, E.; Schlosser, M. J. Org. Chem.
2003, 68, 4693.
Synlett 2013, 24, 2259–2262
© Georg Thieme Verlag Stuttgart · New York