LETTER
Chemoselective Synthesis of 2-Aryloxazolines and Bis-oxazolines
2749
Scheme 3
It is also noteworthy that alkylnitriles did not produce the
corresponding 2-oxazolines under the same reaction con-
ditions. With this objective, a set of competitive reactions
was conducted between arylnitriles and alkylnitriles, the
results of which are shown in Scheme 3. The results indi-
cate that the present protocol is potentially applicable for
the chemoselective conversion of arylnitriles to their cor-
responding 2-oxazolines in the presence of alkylnitriles.
Finta, Z.; Horvath, Z. Tetrahedron Lett. 2002, 43, 3985.
c) Bandgar, B. P.; Pandit, S. S. . Tetrahedron Lett. 2003, 44,
331.
(
2
(
6) (a) Miller, D.; Umbricht, G.; Weber, B.; Pfaltz, A. Helv.
Chim. Acta 1991, 74, 232. (b) Zhou, P.; Blubaum, J. E.;
Burns, C. T.; Natale, N. R. Tetrahedron Lett. 1997, 38, 7019.
7) (a) Clarke, D. S.; Wood, R. Synth. Commun. 1996, 26, 1335.
(b) Jnaneshwara, G. K.; Deshpande, V. H.; Lalithambika,
M.; Ravindranathan, T.; Bedekar, A. V. Tetrahedron Lett.
(
1
998, 39, 459.
8) (a) Corey, E. J.; Ishihara, K. Tetrahedron Lett. 1992, 33,
807. (b) Lafargue, P.; Guenot, P.; Lellouche, J. P.
Heterocycles 1995, 41, 947.
In conclusion, we have demonstrated a new and efficient
method for the synthesis of 2-aryloxazolines using cata-
lytic amounts of Bi(TFA) , Bi(OTf) and BiOClO ·xH O
(
6
3
3
4
2
as novel catalysts. Furthermore, easy handling, low cost
and non-toxicity of the catalysts make this method eco-
friendly and environmentally acceptable. Moreover, high
product yields, short reaction times, easy work-up and
also high degree of chemoselectivity are other noteworthy
advantages of this new method, which will make it a use-
ful and important addition to the present methodologies.
(9) Badiang, J. G.; Aube, J. J. Org. Chem. 1996, 61, 2484.
10) Minakata, S.; Nishimura, M.; Takahashi, T.; Oderaotoshi,
Y.; Komatsu, M. Tetrahedron Lett. 2001, 42, 9019.
11) (a) Reglinski, J. In Chemistry of Arsenic, Antimony and
Bismuth; Norman, N. C., Ed.; Blackie Academic and
Professional: New York, 1998, 403–440. (b) Suzuki, H.;
Ikegami, T.; Matano, Y. Synthesis 1997, 249. (c) Leonard,
N. M.; Wieland, L. C.; Mohan, R. S. Tetrahedron 2002, 58,
(
(
8373. (d) Anderson, A. M.; Blazek, J. M.; Garg, P.; Payne,
B. J.; Mohan, R. S. Tetrahedron Lett. 2000, 41, 1527.
Acknowledgment
(
(
e) Chakraborti, A. K.; Shivani, G. R. Synlett 2003, 1805.
f) Sabitha, G.; Venkata Reddy, E.; Swapna, R.; Mallikarjun
We are thankful to the Office of Graduate Studies of the University
of Isfahan for their financial support.
Reddy, N.; Yadav, J. S. Synlett 2004, 1276. (g) Yadav, J. S.;
Reddy, B. V. S.; Premalatha, K. Synlett 2004, 963.
(
h) Grouch, R. D.; Romany, C. A.; Kreshock, A. C.;
Menconi, K. A.; Zile, J. L. Tetrahedron Lett. 2004, 45,
279. (i) Ghosh, R.; Maiti, S.; Chakraborty, A. Synlett 2005,
References
1
(
1) (a) Genet, J. P.; Thorimbert, S.; Touzin, A. M. Tetrahedron
Lett. 1993, 34, 1159. (b) Wipf, P.; Venkatraman, S. Synlett
115. (j) Nattier, B. A.; Eash, K. J.; Mohan, R. S. Synthesis
2001, 1010.
1997, 1. (c) Li, Q.; Woods, K. W.; Claiborne, A.; Gwaltney,
(12) (a) Mohammadpoor-Baltork, I.; Aliyan, H. Synth. Commun.
1998, 28, 3943. (b) Mohammadpoor-Baltork, I.; Aliyan, H.
Synth. Commun. 1999, 29, 2741. (c) Mohammadpoor-
Baltork, I.; Tangestaninejad, S.; Aliyan, H.; Mirkhani, V.
Synth. Commun. 2000, 30, 2365. (d) Mohammadpoor-
Baltork, I.; Aliyan, H.; Khosropour, A. R. Tetrahedron
2001, 57, 5851. (e) Mohammadpoor-Baltork, I.;
S. L.; Barr, K. J.; Liu, G.; Gehrke, L.; Credo, R. B.; Hua Hui,
Y.; Lee, J.; Warner, R. B.; Kovar, P.; Nukkala, M. A.;
Zielinski, N. A.; Tahir, S. K.; Fitzgerald, M.; Kim, K. H.;
Marsh, K.; Frost, D.; Ng, S.-C.; Rosenberg, S.; Sham, H. L.
Bioorg. Med. Chem. Lett. 2002, 12, 465.
(
(
(
2) (a) Gant, T. G.; Meyers, A. I. Tetrahedron 1994, 50, 2297.
(b) Yang, D.; Yip, Y.-C.; Wang, X.-C. Tetrahedron Lett.
Khosropour, A. R.; Aliyan, H. J. Chem. Res., Synop. 2001,
280. (f) Mohammadpoor-Baltork, I.; Khosropour, A. R.;
Aliyan, H. Synth. Commun. 2001, 31, 3411.
1997, 38, 7083.
3) Greene, T. W.; Wutz, P. G. M. In Protecting Groups in
Organic Synthesis, 2nd ed.; John Wiley and Sons: New
York, 1991.
(g) Mohammadpoor-Baltork, I.; Khosropour, A. R.
Molecules 2001, 996. (h) Firouzabadi, H.; Mohammadpoor-
Baltork, I.; Kolagar, S. Synth. Commun. 2001, 31, 905.
(i) Mohammadpoor-Baltork, I.; Kharamesh, B.; Kolagar, S.
Synth. Commun. 2002, 32, 1633. (j) Mohammadpoor-
Baltork, I.; Khosropour, A. R. Monatsh. Chem. 2002, 133,
189. (k) Mohammadpoor-Baltork, I.; Khodaei, M. M.;
Nikoofar, K. Tetrahedron Lett. 2003, 44, 591.
4) (a) Jiang, Y.; Jiang, Q.; Zhu, G.; Zhang, X. Tetrahedron Lett.
1
997, 38, 215. (b) McManus, H. A.; Barry, S. M.;
Andersson, P. G.; Guiry, P. J. Tetrahedron 2004, 60, 3405.
c) Lee, A.; Kim, W.; Lee, J.; Hyeon, T.; Kim, B. M.
(
Tetrahedron: Asymmetry 2004, 15, 2595.
(5) (a) Vorbrüggen, H.; Krolikiewicz, K. Tetrahedron Lett.
1993, 34, 9353. (b) Cwik, A.; Hell, Z.; Hegedüs, A.;
Synlett 2005, No. 18, 2747–2750 © Thieme Stuttgart · New York