Table 1 Rhodium-catalysed 1,4-addition of diarylindium hydroxides
ð1Þ
In summary, we have developed the rhodium-catalysed 1,4-
addition of organoindium reagents to a,b-unsaturated carbonyl
compounds, demonstrating the utility of diarylindium(III) hydro-
xide as an aryl source with rhodium catalysts.
Yield
Product 3 (%)a
Entry Substrate 1
2 (Ar)
1
2
3
4
1a
2b p-CH3C6H4 3ab
2c o-CH3C6H4 3ac
2d p-CH3OC6H4 3ad
94
99
77
85
This work was supported by Grant-in-Aid for Scientific
Research on Priority Areas 17035044 from The Ministry of
Education, Culture, Sports, Science and Technology (MEXT).
2e p-FC6H4
3ae
Notes and references
5
1b
2a
3ba
91
{ Indium trichloride (221 mg, 1.0 mmol) was placed in an oven-dried, Ar-
purged flask and dissolved with THF (1 mL). Arylmagnesium bromide
(1.0 M THF solution, 2.0 mL, 2.0 mmol) was added dropwise to the
solution at 0 uC. Then, the mixture was stirred at room temperature for
30 min to prepare diarylindium chloride. Water (0.5 mL) was added at 0 uC
to form a white suspension. After the suspension was stirred at room
temperature for 10 min, a solution of substrate 1 (0.5 mmol) in THF
(3.0 mL) and [Rh(OH)(cod)]2 (5.7 mg, 0.0125 mmol, 0.05 equiv of Rh) were
added. The resulting reaction mixture was further stirred for 6 h at room
temperature. Water (10 mL) was added, and the aqueous layer was
extracted with ethyl acetate (15 mL 6 3). The combined organic extracts
were dried over MgSO4. The solvent was removed under reduced pressure
and the residue was purified by preparative thin-layer chromatography
(hexane–ethyl acetate ) to give the product 3.
6
1c
2a
3ca
79
7
1d
1e
1f
2a
2a
2a
2a
2a
3da
3ea
3fa
3ga
3ha
88
73
85b
78
87
1 D. W. Knight in Comprehensive Organic Synthesis, ed. B. M. Trost and
I. Fleming, Pergamon Press, Oxford, 1991, vol. 3, pp. 481–520.
2 (a) K. Fagnou and M. Lautens, Chem. Rev., 2003, 103, 169; (b)
T. Hayashi and K. Yamasaki, Chem. Rev., 2003, 103, 2829.
3 For examples of rhodium-catalysed 1,4-addition of various organome-
tallic reagents, see: (a) [B]: Y. Takaya, M. Ogasawara, T. Hayashi,
M. Sakai and N. Miyaura, J. Am. Chem. Soc., 1998, 120, 5579; (b) [Si]:
T.-S. Huang and C.-J. Li, Chem. Commun., 2001, 2348; (c) S. Oi,
Y. Honma and Y. Inoue, Org. Lett., 2002, 4, 667; (d) T. Koike, X. Du,
A. Mori and K. Osakada, Synlett, 2002, 301; (e) M. Murata,
R. Shimazaki, M. Ishikura, S. Watanabe and Y. Masuda, Synthesis,
2002, 717; (f) [Bi]: S. Venkatraman and C.-J. Li, Tetrahedron Lett., 2001,
42, 781; (g) [Sn]: S. Oi, M. Moro, S. Ono and Y. Inoue, Chem. Lett.,
1998, 83; (h) [Ti]: T. Hayashi, N. Tokunaga, K. Yoshida and J. W. Han,
J. Am. Chem. Soc., 2002, 124, 12102; (i) [Zr]: A. Kakuuchi, T. Taguchi
and Y. Hanzawa, Tetrahedron, 2004, 60, 1293; (j) [Zn]: R. Shintani,
N. Tokunaga, H. Doi and T. Hayashi, J. Am. Chem. Soc., 2004, 126,
6240.
4 (a) P. Cintas, Synlett, 1995, 1087; (b) K. K. Chauhan and C. G. Frost,
J. Chem. Soc., Perkin Trans. 1, 2000, 3015; (c) M. A. Pena,
J. Pe´rez Sestelo and L. A. Sarandeses, Synthesis, 2005, 485; (d)
C.-J. Li, Chem. Rev., 2005, 105, 3095.
5 For an example of 1,4-addition of tetraorganoindium ate complexes,
see: S. Araki, T. Shimizu, S-J. Jin and Y. Butsugan, J. Chem. Soc.,
Chem. Commun., 1991, 824.
6 For an example of Ni-catalysed 1,4-addition of triphenylindium(III), see:
I. Pe´rez, J. Pe´rez Sestelo, M. A. Maestro, A. Mourin˜o and
L. A. Sarandeses, J. Org. Chem., 1998, 63, 10074.
7 K. Takami, H. Yorimitsu, H. Shinokubo, S. Matsubara and K. Oshima,
Org. Lett., 2001, 3, 1997.
8
9
10
11
12
1g
1h
1i
1j
2a
2a
3ia
3ja
57c
8 The product 3aa was obtained in 62% yield and a small amount of 1a
remained when 1.0 equiv. of PhMgBr and 0.5 equiv. of InCl3 were used.
No reaction was observed without the rhodium catalyst.
9 (a) T. Huang, Y. Meng, S. Venkatraman, D. Wang and C.-J. Li, J. Am.
Chem. Soc., 2001, 123, 7451; (b) T. Hayashi, M. Takahashi, Y. Takaya
and M. Ogasawara, J. Am. Chem. Soc., 2002, 124, 5052.
13
40
10 C. Defieber, J.-F. Paquin, S. Serna and E. M. Carreira, Org. Lett., 2004,
6, 3873. See also: R. Shintani, T. Kimura and T. Hayashi, Chem.
Commun., 2005, 3213 and references therein.
a
b
Isolated yields. 3 equiv of 2a. 1i remained after workup.
c
This journal is ß The Royal Society of Chemistry 2005
Chem. Commun., 2005, 5676–5677 | 5677