246
H. Zhang et al.
LETTER
(4) an der Heiden, M. R.; Frey, G. D.; Plenio, H.
Although the above procedure is clearly successful for the
coupling reaction between aryl iodides and alcohols, us-
ing the same procedure for aryl bromide provided a low
yield of the ether (entry 13). Further studies into the scope
and mechanism of this reaction are currently underway in
our laboratories.
Organometallics 2004, 23, 3548.
(5) For some recent reviews on copper-catalyzed Ullmann-type
reaction, see: (a) Kunz, K.; Scholz, U.; Ganzer, D. Synlett
2003, 2428. (b) Frlan, R.; Kikelj, D. Synthesis 2006, 2271.
(c) Beletskaya, I.; Cheprakov, A. Coord. Chem. Rev. 2004,
248, 2337. (d) Ley, S.; Thomas, A. Angew. Chem. Int. Ed.
2003, 42, 5400.
(6) (a) Wolter, M.; Nordmann, G. E.; Buchwald, S. L. Org. Lett.
2002, 4, 973. (b) Job, G.; Buchwald, S. L. Org. Lett. 2002, 4,
3703. (c) Hosseinzadeh, R.; Tajbakhsh, M.; Mohadjerani,
M.; Alikarami, M. Synlett 2005, 1101. (d) Manbeck, G. F.;
Lipman, A. Jr.; Stockland, R. A.; Freidl, A.; Hasler, A.;
Stone, J.; Guzei, I. J. Org. Chem. 2005, 70, 244.
(7) (a) Ma, D.; Zhang, Y.; Yao, J.; Wu, S.; Tao, F. J. Am. Chem.
Soc. 1998, 120, 12459. (b) Ma, D.; Xia, C. Org. Lett. 2001,
3, 2583. (c) Ma, D.; Cai, Q.; Zhang, H. Org. Lett. 2003, 5,
2453. (d) Ma, D.; Cai, Q. Org. Lett. 2003, 5, 3799.
(e) Zhang, H.; Cai, Q.; Ma, D. J. Org. Chem. 2005, 70, 5164.
(8) N,N-Dimethylglycine-Promoted Coupling Reactions of
Aryl Halides with Alcohols; General Procedure: A re-
sealable tube or test tube with a removable cap was charged
with CuI (10 mol%), N,N-dimethylglycine·HCl (20 mol%),
Cs2CO3 (2 equiv), and aryl halide (if solid, 2 mmol). The
tube was evacuated and backfilled with N2 (3 cycles).
Alcohol (2 mL) and aryl halide (if liquid, 2 mmol) were
added by syringe at r.t. under nitrogen. The sealed or capped
tube was put into the oil bath that was preheated to 110 °C
and the reaction mixture was stirred for the time specified.
The cooled mixture was partitioned between H2O (10 mL)
and EtOAc or Et2O (20 mL). The organic layer was
separated, and the aqueous layer was extracted with EtOAc
or Et2O (10 mL) each time until TLC showed no trace of
product left in the aqueous layer. The combined organic
layers were washed with brine, dried over Na2SO4 and
concentrated. Purification of the residue by flash
In conclusion, we have demonstrated that N,N-dimethyl-
glycine is an excellent ligand for Ullmann-type coupling
of aryl iodides and aliphatic alcohols. The present reac-
tion, which worked under our relatively mild conditions
using an experimentally simple catalytic system, was
applicable for a wide scope of substrates. Given these at-
tributes, it should find applications in organic synthesis.
Acknowledgment
The authors are grateful to Education Commission of Shanghai
Municipality (grant 05AX12 and B.99-0303-06-034) for their
financial support.
References and Notes
(1) (a) Yamazaki, N.; Washio, I.; Shibasaki, Y.; Mitsuru Ueda,
M. Org. Lett. 2006, 8, 2321. (b) Asano, M.; Inoue, M.;
Katoh, T. Synlett 2005, 2599. (c) Jiang, H.; Leger, J.-M.;
Huc, I. J. Am. Chem. Soc. 2003, 125, 3448. (d) Bolm, C.;
Hildebrand, J. P.; Muñiz, K.; Hermanns, N. Angew. Chem.
Int. Ed. 2001, 40, 3284. (e) Gu, W. X.; Jing, X. B.; Pan, X.
F.; Chan, A. S. C.; Yang, T. K. Tetrahedron 2000, 41, 6079.
(f) Matsumoto, Y.; Uchida, W.; Nakahara, H.; Yanagisawa,
I.; Shibanuma, T.; Nohira, H. Chem. Pharm. Bull. 2000, 48,
428. (g) Cao, B.; Haengsoon Park, H.; Joullie, M. M. J. Am.
Chem. Soc. 2002, 124, 520. (h) Temal-Laïb, T.; Chastanet,
J.; Zhu, J. J. Am. Chem. Soc. 2002, 124, 583. (i) Kawata, S.;
Hirama, M. Tetrahedron Lett. 1998, 39, 8707.
chromatography on silica gel [2 × 20 cm, PE (30–60 °C)–
EtOAc or Et2O] gave the desired product.
(9) 4-Benzoxyanisole (Table 2, Entry 3): white solid; mp 60–
62 °C (Lit.6a mp 63 °C). 1H NMR (400 MHz, CDCl3): d =
7.25–7.43 (m, 5 H), 6.91 (d, J = 8.9 Hz, 2 H), 6.83 (d, J = 8.9
Hz, 2 H), 5.02 (s, 2 H), 3.77 (s, 3 H). MS (EI): m/z = 214
[M+], 123, 95, 92, 91, 65, 63, 41.
(10) 3-(3-Methylbut-2-enyloxy)pyridine (Table 2, Entry 20):
yellow oil. 1H NMR (500 MHz, CDCl3): d = 8.32 (s, 1 H),
8.21 (s, 1 H), 7.20 (s, 2 H), 5.46–5.49 (m, 1 H), 4.56 (d, J =
7.0 Hz, 2 H), 1.80 (s, 3 H), 1.75 (s, 3 H). 13C NMR (125
MHz, CDCl3): d = 155.0, 141.9, 139.0, 138.1, 123.8, 121.4,
119.0, 65.1, 25.8, 18.3. MS (EI): m/z = 163 [M+], 162, 95, 69,
68, 67, 41. HRMS (EI): m/z [M+] calcd for C10H13NO:
163.0997; found: 163.1002.
(j) Thompson, A.; Delaney, A.; James, M.; Hamby, J.;
Schroeder, M.; Spoon, T.; Crean, S.; Showalter, H. D. H.;
Denny, W. J. Med. Chem. 2005, 48, 4628.
(2) Lindley, J. Tetrahedron 1984, 40, 1433.
(3) For some recent reports on palladium-catalyzed aryl ether
synthesis, see: (a) Vorogushin, A. V.; Huang, X.; Buchwald,
S. L. J. Am. Chem. Soc. 2005, 127, 8146. (b) Kataoka, N.;
Shelby, Q.; Stambuli, J.; Hartwig, J. J. Org. Chem. 2002, 67,
5553. (c) Kuwabe, S.; Torraca, K. E.; Buchwald, S. L. J. Am.
Chem. Soc. 2001, 123, 12202. (d) Prim, D.; Campagna, J.-
M.; Joseph, D.; Andrioletti, B. Tetrahedron 2002, 58, 2041.
(e) Hartwig, J. F. Angew. Chem. Int. Ed. 1998, 37, 2046.
(f) Palucki, M.; Wolfe, J.; Buchwald, S. L. J. Am. Chem. Soc.
1997, 119, 3395. (g) Torraca, K.; Huang, X.; Parrish, C.;
Buchwald, S. J. Am. Chem. Soc. 2001, 123, 10770.
Synlett 2007, No. 2, 243–246 © Thieme Stuttgart · New York