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Journal of the American Chemical Society
1
2
3
4
9
452-9474. (d) Yamaguchi, J.; Yamaguchi, A. D.; Itami, K.
Angew. Chem. Int. Ed. 2012, 51, 8960-9009.
13) Zhang, W.; Ready, J. M. Angew. Chem. Int. Ed. 2014,
3, 8980-8984.
14) Kohnen, A. L.; Mak, X. Y.; Lam, T. Y.; Dunetz, J. R.;
Danheiser, R. L. Tetrahedron 2006, 62, 3815-3822.
15) For selected Danheiser benzannulation reactions,
see: (a) Danheiser, R. L.; Gee, S. K. J. Org. Chem. 1984, 49,
672-1674. (b) Xu, S. L.; Moore, H. W. J. Org. Chem. 1989,
4, 4024-4026. (c) Danheiser, R. L.; Brisbois, R. G.; Kow-
alczyk, J. J.; Miller, R. F. J. Chem. Am. Soc. 1990, 112, 3093-
100. (d) Turnbull, P.; Moore, H. W. J. Org. Chem. 1995,
0, 644-649. (e) Dudley, G. B.; Takaki, K. S.; Cha, D. D.;
(22) (a) dpp-hexane is a poor ligand for palladium-
catalyzed CO/C H copolymerization. See: Leeuwen, P.
5
6
7
8
9
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
4
4
4
5
5
5
5
5
5
5
5
5
5
6
2
4
(
W. N. M. v.; Freixa, Z. In Modern Carbonylation Methods;
Wiley-VCH Verlag GmbH & Co. KGaA: 2008, p 10. (b) For
bite angle of Pd[PH (CH2) PH ], see: van Zeist, W.-J.;
5
(
2
6
2
Visser, R.; Bickelhaupt, F. M. Chem. Eur. J. 2009, 15, 6112-
6115.
(23) Commercially available from Chendu Aofan Pharm-
tech Co., Ltd (TEL 86-28-85655382) or available from a 1-
pot iodination-sulfonylation of the corresponding indole.
See supporting information for details.
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
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7
8
9
0
1
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5
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9
0
(
1
5
3
6
(24) N-Cbz gave 84% yield of impure material in the
coupling reaction; N-Ns decomposed during coupling
reaction; N-Ts had poor solubility for coupling reaction
and gave 21% yield.
Danheiser, R. L. Org. Lett. 2000, 2, 3407-3410. (f) Austin,
W. F.; Zhang, Y.; Danheiser, R. L. Org. Lett. 2005, 7, 3905-
1
3
908. (g) Mak, X. Y.; Crombie, A. L.; Danheiser, R. L. J.
(25) H NMR key parameters: nt = 32, d1= 4. The graph in
Org. Chem. 2011, 76, 1852-1873. (h) Lam, T. Y.; Wang, Y.-
P.; Danheiser, R. L. J. Org. Chem. 2013, 78, 9396-9414. (i)
Willumstad, T. P.; Haze, O.; Mak, X. Y.; Lam, T. Y.; Wang,
Y.-P.; Danheiser, R. L. J. Org. Chem. 2013, 78, 11450-11469.
Scheme 1B was generating by assuming [20]% + [22]% +
1
[23]% = 100%. No other products were observed in the H
NMR spectra. The hetero/homo-dimer selectivity did not
change over the course of the reaction.
(26) The starting material was reused once.
(27) (a) Schmidt, A. H.; Debo, M.; Wehner, B. Synthesis
1990, 1990, 237-242. (b) Sejwal, P.; Han, Y.; Shah, A.; Luk,
Y.-Y. Org. Lett. 2007, 9, 4897-4900. (c) Li, J.; Han, Y.;
Freedman, T. B.; Zhu, S.; Kerwood, D. J.; Luk, Y.-Y. Tetra-
hedron Lett. 2008, 49, 2128-2131.
(
1
j) Bai, Y.; Yin, J.; Liu, Z.; Zhu, G. J. Org. Chem. 2015, 80,
0226-10233.
16) Formation of carbazoles using 6π electrocyclization,
(
see: (a) Bian, M.; Wang, Z.; Xiong, X.; Sun, Y.; Matera, C.;
Nicolaou, K. C.; Li, A. J. Chem. Am. Soc. 2012, 134, 8078-
8081; (b) Meng, Z.; Yu, H.; Li, L.; Tao, W.; Chen, H.; Wan,
M.; Yang, P.; Edmonds, D. J.; Zhong, J.; Li, A. Nat. Com-
mun. 2015, 6, 6096.
(
(28) We added 2.5 equivalents of the ynol ether every 4
o
hours. Batchwise addition gave 42% of 37 at 60 C com-
17) (a) Lu, Z.; Li, Y.; Deng, J.; Li, A. Nat. Chem. 2013, 5,
pared to 38% yield when all reagents were combined at
the beginning of the reaction.
679-684; (b) Xiong, X.; Li, Y.; Lu, Z.; Wan, M.; Deng, J.;
Wu, S.; Shao, H.; Li, A. Chem. Commun. 2014, 50, 5294-
5297; (c) Li, J.; Yang, P.; Yao, M.; Deng, J.; Li, A. J. Chem.
Am. Soc. 2014, 136, 16477-16480; (d) Yang, M.; Li, J.; Li, A.
Nat. Commun. 2015, 6, 6445. (e) Yang, M.; Yang, X.; Sun,
H.; Li, A. Angew. Chem. Int. Ed. 2016, 55, 2851-2855. (f)
Yang, P.; Yao, M.; Li, J.; Li, Y.; Li, A. Angew. Chem. Int. Ed.
2016, 55, 6964-6968.
(18) Formation of multisubstituted arenes, see also: (a)
Anderson, E. A.; Alexanian, E. J.; Sorensen, E. J. Angew.
Chem. Int. Ed. 2004, 43, 1998-2001. (b) Ohmori, K.; Mori,
K.; Ishikawa, Y.; Tsuruta, H.; Kuwahara, S.; Harada, N.;
Suzuki, K. Angew. Chem. Int. Ed. 2004, 43, 3167-3171. (c)
Greshock, T. J.; Funk, R. L. Org. Lett. 2006, 8, 2643-2645.
(d) Sloman, D. L.; Mitasev, B.; Scully, S. S.; Beutler, J. A.;
Porco, J. A. Angew. Chem. Int. Ed. 2011, 50, 2511-2515.
(19) Löffler, A.; Himbert, G. Synthesis 1992, 1992, 495-
498.
(29) (a) Richter, J. M.; Whitefield, B. W.; Maimone, T. J.;
Lin, D. W.; Castroviejo, M. P.; Baran, P. S. J. Chem. Am.
Soc. 2007, 129, 12857-12869. (b) DeMartino, M. P.; Chen,
K.; Baran, P. S. J. Chem. Am. Soc. 2008, 130, 11546-11560.
(30) (a) Zuo, Z.; Xie, W.; Ma, D. J. Chem. Am. Soc. 2010,
132, 13226-13228. (b) Zi, W.; Zuo, Z.; Ma, D. Acc. Chem.
Res. 2015, 48, 702-711.
(31) The iodinated product was the only product we iso-
lated after the reaction.
(32) 41 could exist as a di-anion or one of several mono-
anions.
(33) See supporting information for details.
(34) For benzenesulfonate acting as an oxidant in the
Shapiro reaction, see: Adlington, R. M.; Barrett, A. G. M.
Acc. Chem. Res. 1983, 16, 55-59.
(35) An alternative mechanism involves migration of the
benzenesulfonate from the indole nitrogen to the pheno-
(20) Gordon, J. R.; Nelson, H. M.; Virgil, S. C.; Stoltz, B.
M. J. Org. Chem. 2014, 79, 9740-9747.
(21) (a) van Leeuwen, P. W. N. M.; Zuideveld, M. A.;
Swennenhuis, B. H. G.; Freixa, Z.; Kamer, P. C. J.; Goubitz,
K.; Fraanje, J.; Lutz, M.; Spek, A. L. J. Chem. Am. Soc.
2003, 125, 5523-5539. (b) For review, see: van Leeuwen, P.
W. N. M.; Kamer, P. C. J.; Reek, J. N. H.; Dierkes, P. Chem.
Rev. 2000, 100, 2741-2770.
late anion to form an ArOSO Ph intermediate. Enolate
2
-
2
addition to the aromatic ring with loss of PhSO
and tau-
tomerization would form carbazole 41.
(36) Wing-Wah, S. Tetrahedron Lett. 1993, 34, 6223-6224.
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