Angewandte
Chemie
activation/borylation reaction. The regioselectivity of the
process can be switched by a slight change in the reaction
[1] a) C. C. Tzschucke, J. M. Murphy, J. F. Hartwig, Org. Lett. 2007, 9,
761; b) T. Ishiyama, J. Takagi, Y. Yonekawa, J. F. Hartwig, N.
Miyaura, Adv. Synth. Catal. 2003, 345, 1103; c) I. A. I. Mkhalid,
D. N. Coventry, D. Albesa-Jove, A. S. Batsanov, J. A. K. Howard,
R. N. Perutz, T. B. Marder, Angew. Chem. 2006, 118, 503; Angew.
Chem. Int. Ed. 2006, 45, 489; d) J.-Y. Cho, M. K. Tse, D. Holmes,
R. E. Maleczka, M. R. Smith, Science 2002, 295, 305; e) R. E.
Maleczka, J. Shi, D. Holmes, M. R. Smith, J. Am. Chem. Soc. 2003,
125, 7792; f) N. Miyaura, Imeboron-XII Conference, IL-03, 2005,
Sedai, Japan.
À
conditions. To our knowledge this is the first one-pot C C
À
bond-forming reaction that involves catalytic C H bond
functionalization of unactivated alkenes based on boronation.
Experimental Section
Allylation reactions (Method A):
A
mixture of catalyst
2
(0.003 mmol, 2 mol%, 2 mg), boronate 3 (0.15 mmol, 38 mg), and
DBU (0.075 mmol, 11.4 mg) was dissolved in neat 1a (1.97 mmol,
0.2 mL). Then this reaction mixture was stirred at 708C for 4 h. After
the reaction mixture had cooled to room temperature, the appro-
priate aldehyde 6a–d (0.18 mmol) was added to the mixture, and
stirring was continued for the times and temperatures given in Table 1
(see column labeled Coupling). The crude reaction mixture was
concentrated to dryness, and the residue was purified by silica gel
column chromatography.
Vinyl functionalization (Method B): A mixture of catalyst 2
(0.003 mmol, 2 mol%, 2 mg) and boronate 3 (0.15 mmol, 38 mg) was
dissolved in neat 1a–c (0.1mL). The reaction mixture was stirred for
the given times and temperatures in Table 1(Boronation). After the
reaction mixture had cooled to room temperature, it was diluted with
a dioxane/water (4:1) mixture (0.25 mL). The appropriate aryl iodides
5a–c (0.15 mmol), Cs2CO3 (0.30 mmol, 97 mg), and [Pd(PPh3)4]
(0.0075 mmol, 5 mol%, 8 mg) were added. The reaction mixture
was stirred for the times and temperatures given in Table 1
(Coupling).
[2] a) D. G. Hall, Boronic Acids. Preparation, Applications in
Organic Synthesis and Medicine, Wiley-VCH, Weinheim, 2005;
b) J. W. J. Kennedy, D. G. Hall, Angew. Chem. 2003, 115, 4880;
Angew. Chem. Int. Ed. 2003, 42, 4732.
[3] a) S. Sebelius, V. J. Olsson, O. A. Wallner, K. J. Szabꢀ, J. Am.
Chem. Soc. 2006, 128, 8150; b) V. J. Olsson, S. Sebelius, N.
Selander, K. J. Szabꢀ, J. Am. Chem. Soc. 2006, 128, 4588; c) N.
Selander, S. Sebelius, C. Estay, K. J. Szabꢀ, Eur. J. Org. Chem.
2006, 4085; d) S. Sebelius, O. A. Wallner, K. J. Szabꢀ, Org. Lett.
2003, 5, 3065; e) S. Sebelius, K. J. Szabꢀ, Eur. J. Org. Chem. 2005,
2539; f) G. W. Kabalka, B. Venkataiah, G. Dong, J. Org. Chem.
2004, 69, 5807.
[4] a) R. B. Coapes, F. E. S. Souza, R. L. Thomas, J. J. Hall, T. B.
Marder, Chem. Commun. 2003, 614; b) A. Caballero, S. Sabo-
Etienne, Organometallics 2007, 26, 1191; c) Y. Yamamoto, R.
Fujikawa, T. Umemoto, N. Miyaura, Tetrahedron 2004, 60, 10695.
[5] a) N. Miyaura, A. Suzuki, Chem. Rev. 1995, 95, 2457; b) A. Suzuki,
J. Organomet. Chem. 1999, 576, 147; c) S. R. Chemler, D. Trauner,
S. J. Danishefsky, Angew. Chem. 2001, 113, 4676; Angew. Chem.
Int. Ed. 2001, 40, 4544; d) N. Miyaura, Top. Curr. Chem. 2002, 219,
11; e) S. Kotha, K. Lahiri, D. Kashinath, Tetrahedron 2002, 58,
9633.
Received: June 8, 2007
Published online: August 2, 2007
[6] a) T. M. Boller, J. M. Murphy, M. Hapke, T. Ishiyama, N. Miyaura,
J. F. Hartwig, J. Am. Chem. Soc. 2005, 127, 14263; b) T. Ishiyama,
J. Takagi, K. Ishida, N. Miyaura, J. Am. Chem. Soc. 2002, 124, 390;
c) T. Ishiyama, N. Miyaura, Chem. Rec. 2004, 3, 271; d) P. Nguyen,
H. P. Blom, S. A. Westcott, N. J. Taylor, T. B. Marder, J. Am.
Chem. Soc. 1993, 115, 9329.
À
Keywords: alkenes · allylation · boron · C H activation ·
homogeneous catalysis
.
Angew. Chem. Int. Ed. 2007, 46, 6891 –6893
ꢀ 2007 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim