3
Bode, H. B.; Heermann, R. Nat. Chem. Biol., 2013,
9, 573-578.
3. (a) Kozytska, M. V.; Dudley, G. B. Tetrahedron Lett.
2008, 49, 2899-2901. (b) Larsson, R.; Sterner, O.;
Johansson, M. Org. Lett. 2009, 11, 657-660. (c)
Nelson, H. M.; Gordon, J. R.; Virgil, S. C.; Stoltz, B.
M. Angew. Chem., Int. Ed. 2013, 52, 6699-6703. (d)
Wright, B. J. D.; Hartung, J.; Peng, F.; van dewater,
R.; Liu, H.; Tan, Q.-H.; Chou, T.-C.; Danishefsky, S.
J. J. Am. Chem. Soc. 2008, 130, 16786-16790. (e)
Jeso, V.; Micalizio, G. C. J. Am. Chem. Soc. 2010,
132, 11422-11424. (f) Hayakawa, I.; Takemura, T.;
Fukasawa, E.; Ebihara, Y.; Sato, N.; Nakamura, T.;
Suenaga, K.; Kigoshi, H. Angew. Chem. Int. Ed.
2010, 49, 2401-2405.
4. (a) Morrison, L. R.; Dickinson, J. M.; Ahmed, R.;
Fairlamb, I. J. S. Tetrahedron Lett. 2002, 43, 8853-
8857. (b) Afarinkia, K.; Berna-Canovas, J.
Tetrahedron Lett. 2000, 41, 4955-4958. (c) Chen, C.
H.; Liao, C. C. Org. Lett. 2000, 2, 2049-2052. (d)
Tam, T. F.; Coles, P. Synthesis 1988, 383-386. (e)
Afarinkia, K.; Vinader, V.; Nelson, T. D.; Posner, G.
H. Tetrahedron 1992, 48, 9111-9171.
5. (a) Izumi, T.; Nishimoto, Y.; Kohei, K.; Kasahara,
A. J. Heterocycl. Chem. 1990, 27, 1419-1550. (b)
Sakamoto, T.; Kondo, Y.; Yamanaka, H.
Heterocycles 1988, 27, 453-456
Figure 2: Plausible reaction mechanism
6. (a) Sakamoto, T.; Kondo, Y.; Yasuhara, A.;
Yamanaka, H. Tetrahedron 1991, 47, 1877-1886. (b)
Rossi, R.; Bellina, F.; Biagetti, M.; Catanese, A.;
Mannina, L. Tetrahedron Lett. 2001, 41, 5281-5286.
(c) Bellina, F.; Ciucci, D.; Vergamini, P.; Rossi, R.
Tetrahedron 2000, 56, 2533-2545.
7. (a) Sakamoto, T.; Kondo, Y.; Yamanaka, H.
Heterocycles 1988, 27, 2225-2249. (b) Sakamoto, T.;
Annaka, M.; Kondo, Y.; Yamanaka, H. Chem.
Pharm. Bull. 1986, 34, 2754-2759
mediated ethyl cleavage and formed the key organometallic
intermediate C in 6-endo-dig fashion. Subsequently, coordination
and insertion of olefin into the intermediate C forms another
organometallic intermediate
E which undergoes reductive
elimination to produce the desired product 3 and Pd(0) species F.
Finally the catalytic cycle is completed by regeneration of the
active Pd(II) species A through the oxidation of F with the help
of oxidant AgOAc.
In summary we have demonstrated tandem one pot Pd(II)
catalyst with X-Phos as a ligand to improve the efficiency of the
catalyst to get highly regioselective and efficient 6-endo-dig
cyclization strategies for the syntheses of multisubstituted 2-
pyrone derivetives with good and excellent yields. This
methodology may exhibit wide range of applications in the
construction of biologically active complex heterocycles.
8. Mochida S.; Hirano, K.; Satoh, T.; Miura, M., J.
Org. Chem. 2009, 74, 6295-6298.
9. Itoh, M.; Shimizu, M.; Hirano, K.; Satoh, T.; Miura,
M., J. Org. Chem. 2013, 78, 11427-11432.
10. Fukuyama, T.; Higashibeppu, Y.; Yamaura, R.;
Ryu, I. Org. Lett. 2007, 9, 587-589.
11. Luo, T.; Schreiber, S. L.; Angew. Chem. Int. Ed.
2007, 46, 8250-8253.
Acknowledgments
12. Bellina, F.; Biagetti, M.; Carpita, A.; Rossi, R.
Tetrahedron 2001, 57, 2857-2870.
We are grateful to DST [Grant No. SB/FT/CS-012/2014] and
CSIR [Grant No. 02(0201)/14/EMR-II] for funds and fellowship
to RSP and SS respectively.
13. (a) Yao, T.; Larock, R. C. Tetrahdron Lett. 2002, 43,
7401-7404. (b) Yao, T.; Larock, R. C. J. Org. Chem.
2003, 68, 5936-5942. (c) Bellina, F.; Biagetti, M.;
Carpita, A.; Rossi, R. Tetrahedron 2001, 57, 2857-
2870. (d) Wang, Y.; J. Burton, D. J. Org. Chem.
2006, 71, 3859-3862.
14. (a) Douglas, C. J.; Sklenicka, H. M.; Shen, H. C.;
Mathias, D. S.; Degen, S. J.; Golding, G. M.;
Morgan, C. D.; Shih, R. A.; Mueller, K. L.; Scurer,
L. M.; Johnson, E. W.; Hsung, R. P. Tetrahedron
1999, 55, 13683-13696. (b) Ma, S.; Yu, S.; Yin, S. J.
Org. Chem. 2003, 68, 8996-9002. (c) Hachiya, I.;
Shibuya, H.; Shimizu, M. Tetrahedron Lett. 2003,
44, 2061-2063. (d) Gilbreath, S. G.; Harris, C. M.;
References and notes
1. (a) McGlacken, G. P.; Fairlamb, J. S. Nat. Prod. Rep.
2005, 22, 369−385. (b) Goel, A.; Ram, V. J.
Tetrahedron 2009, 65, 7865−7913. (c) Kamano, Y.;
Nogawa, T.; Yamashita, A.; Hayashi, M.; Inoue, M.;
Drasar, P.; Pettit, G. R. J. Nat. Prod. 2002, 65,
1001−1005.
2. (a) Hirano, K.; Minakata, S.; Komatsu, M.;
Mizuguchi, J. J. Phys. Chem. A, 2002, 106, 4868-
4871. (b) Brachmann, A. O.; Brameyer, S.; Kresovic,
D.; Hitkova, I.; Kopp, Y.; Manske, C.; Schubert, K.;