2
18
Q.-F. Zhou et al.
LETTER
(
3) (a) Pigge, F. C.; Zheng, Z. Tetrahedron Lett. 2001, 42,
259. (b) Pigge, F. C.; Ghasedi, F.; Zheng, Z.; Rath, N. P.;
Nichols, G.; Chickos, J. S. J. Chem. Soc., Perkin Trans. 2
000, 2458. (c) Pigge, F. C.; Ghasedi, F.; Rath, N. P.
H
O
B
NR3
O
8
H
O
B
R
O
2
R
Tetrahedron Lett. 1999, 40, 8045. (d) Matsuda, K.;
Nakamura, N.; Iwamura, H. Chem. Lett. 1994, 1765.
(e) Balasubramanian, K.; Selvaraj, S.; Venkataramani, P. S.
Synthesis 1980, 29. (f) Elghamry, I. Synthesis 2003, 2301.
R
3
R N
R
R
O
10
H B
11
O
(
g) Pena, M. A.; Sestelo, J. P.; Sarandeses, L. A. Synthesis
R
2005, 485. (h) Abdel-Khalik, M. M.; Elnagdi, M. H. Synth.
Commun. 2002, 32, 159. (i) Almazroa, S.; Elnagdi, M. H.;
El-Din, A. M. S. J. Heterocycl. Chem. 2004, 41, 267.
R3N
O
NR3
O
O
NR3
O
(4) Yang, J.; Verkade, G. J. Am. Chem. Soc. 1998, 120, 6834.
(
5) (a) Modern Arene Chemistry; Astruc, D., Ed.; Wiley-VCH:
Weinheim, 2002. (b) The Chemistry of Phenols; Rappoport,
Z., Ed.; Wiley-VCH: New York, 2003.
R
R
R
R
3
(
6) (a) Nefzi, A.; Ostresh, J. M.; Houghten, R. A. Chem. Rev.
1997, 97, 449. (b) Simon, C.; Constantieux, T.; Rodriguez,
J. Eur. J. Org. Chem. 2004, 4957. (c) Li, C. Chem. Rev.
R
O
R
O
13
12
2005, 105, 3095.
Scheme 4 Plausible mechanism for the cyclotrimerization reaction
(7) (a) Hanédanian, M.; Loreau, O.; Sawicki, M.; Taran, F.
Tetrahedron 2005, 61, 2287. (b) Trost, B. M.; Dake, G. R. J.
Am. Chem. Soc. 1997, 119, 7595. (c) Hanédanian, M.;
Loreau, O.; Taran, F.; Mioskowski, C. Tetrahedron Lett.
which is endowed with high acceptor capability in conju-
gate addition. The mechanistic details of this reaction
need further investigation.
2004, 45, 7035. (d) Xue, S.; Zhou, Q.; Zheng, X. Synth.
Commun. 2005, 35, 3027.
(
8) (a) Yamada, Y. M. A.; Ikegami, S. Tetrahedron Lett. 2000,
41, 2165. (b) McDougal, N. T.; Schaus, S. E. J. Am. Chem.
Soc. 2003, 125, 12094. (c) Shi, M.; Liu, Y. H. Org. Biomol.
Chem. 2006, 4, 1468.
In summary, we have described a new and simple organo-
catalytic process of cyclotrimerization of acetylenic ke-
tones. The reaction was catalyzed by DMAP as Lewis
base in the presence of 2,4-pentanedione. Both aliphatic
and aromatic acetylenic ketones reacted smoothly under
mild conditions, affording 1,3,5-trisubstituted benzenes
with excellent yields. 2,4-Pentanedione was used as co-
catalyst to promote this annulation efficiently. Efforts are
underway to ascertain the scope and limitations of this
reaction.
(9) For selected recent reactions catalyzed by amines, see:
(
(
a) Wang, Y.; Cui, S.; Lin, X. Org. Lett. 2006, 8, 1241.
b) Sonye, J. P.; Koide, K. Org. Lett. 2006, 8, 199. (c) Shi,
Y.; Shi, M. Org. Lett. 2005, 7, 3057. (d) Tejedor, D.;
Santos-Exposito, A.; Gonzalez-Cruz, D.; Marrero-Tellado,
J. J.; Garcia-Tellado, F. J. Org. Chem. 2005, 70, 1042.
(e) Bella, M.; Jørgensen, K. A. J. Am. Chem. Soc. 2004, 126,
5672. (f) Li, C.; Shi, M. Org. Lett. 2003, 5, 4273.
(
10) Typical Procedure.
A round-bottomed flask, equipped with a stirring bar, was
charged with 2,4-pentanedione (0.15 mmol) and acetylenic
ketone (0.3 mmol) dissolved in CH Cl (2 mL) followed by
DMAP (0.03 mmol). The reaction was run at r.t. for the
indicated time (monitored by TLC). The reaction was
concentrated under reduced pressure on a rotary evaporator
and purified by silica gel chromatography using PE–EtOAc
Acknowledgment
2
2
This work is supported by the Natural Science Foundation of Anhui
province (050460302) and NSFC (20572104).
References and Notes
(
10:1 to 3:1).
1
Compound 3a: H NMR (300 MHz, CDCl ): d = 8.63 (s, 3
(1) (a) Shore, N. E. In Comprehensive Organic Synthesis, Vol.
3
1
3
H), 2.64 (s, 9 H) ppm. C NMR (75 MHz, CDCl ): d =
5; Trost, B. M.; Fleming, I.; Paquette, L. A., Eds.; Pergamon:
3
1
96.7, 138.0, 131.8, 26.9 ppm. IR (KBr): n = 1690, 1227
Oxford, 1991, 1129–1162. (b) Grotjahn, D. B. In
–
1
+
cm . HRMS (EI): m/z calcd for C H O [M] : 204.0786;
Comprehensive Organometallic Chemistry II, Vol. 12;
Hegedus, L. S.; Abel, E. W.; Stone, F. G. A.; Wilkinson, G.,
Eds.; Pergamon: Oxford, 1995, 741–770. (c) Lautens, M.;
Klute, W.; Tam, W. Chem. Rev. 1996, 96, 49. (d) Frühauf,
H.-W. Chem. Rev. 1997, 97, 523. (e) Yamamoto, Y.; Ishii,
J.; Nishiyama, H.; Itoh, K. J. Am. Chem. Soc. 2004, 126,
12 12
3
found: 204.0791.
1
Compound 3b: H NMR (300 MHz, CDCl ): d = 8.56 (s, 3
3
H), 7.25–7.10 (m, 15 H), 3.31 (t, J = 7.5 Hz, 6 H), 3.03 (t,
J = 7.5 Hz, 6 H) ppm. C NMR (75 MHz, CDCl ): d =
97.9, 140.8, 137.8, 131.3, 128.7, 128.6, 126.4, 40.8, 30.1
ppm. IR (KBr): n = 1694, 1162 cm . HRMS (EI): m/z calcd
for C H O [M] : 474.2195; found: 474.2192.
Compound 6: H NMR (300 MHz, CDCl ): d = 8.49 (d,
J = 1.5 Hz, 2 H), 8.29 (d, J = 1.5 Hz, 1 H), 7.76 (d, J = 7.6
1
3
3
1
–
1
3712. (f) Meriwether, L. S.; Colthup, E. C.; Kennerly, G.
+
W.; Reusch, R. N. J. Org. Chem. 1961, 26, 5155.
33 30
3
1
(2) (a) Saito, S.; Yamamoto, Y. Chem. Rev. 2000, 100, 2901.
3
(
b) Ardizzoia, G. A.; Brenna, S.; LaMonica, G.; Maspero,
A.; Masciocchi, N. J. Organomet. Chem. 2002, 649, 173.
c) Kotha, T.; Brahmachary, E.; Lahiri, K. Eur. J. Org.
Hz, 4 H), 7.57–7.54 (m, 2 H), 7.47–7.42 (m, 4 H), 2.63 (s, 3
1
3
H) ppm. C NMR (75 MHz, CDCl ): d = 195.4, 193.9,
(
3
1
37.4, 136.4, 135.4, 133.8, 132.2, 131.5, 129.0, 127.6, 25.8
ppm. IR (KBr): n = 1691, 1662, 1242 cm . HRMS (EI):
m/z calcd for C H O [M] : 328.1099; found: 328.1092.
Chem. 2005, 4741. (d) Xi, C.; Chen, C.; Lin, J.; Hong, X.
Org. Lett. 2005, 7, 347. (e) Zhou, L.; Jiang, H.; Huang, J.;
Tang, J. Chin. J. Org. Chem. 2006, 26, 1.
–
1
+
22 16
3
Synlett 2007, No. 2, 215–218 © Thieme Stuttgart · New York