Second generation palladium-catalyzed cyclo-alkenylation in iridoid lactone synthesis: Total syntheses of (±)-onikulactone and (±)- mitsugashiwalactone

Heterocycles

Volumn 82, Issue 2, 2010, Pages 1705-1708

  Saeki, Megumi ^a   Toyota, Masahiro ^a  

^a Osaka Prefecture University   (Japan)

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Indexed keywords

EID: 79952758749     PISSN: 03855414     EISSN: 18810942     Source Type: Journal    
DOI: 10.3987/COM-10-S(E)115     Document Type: Article

References (11)

1. (a) Catalytic conditions: A. Hibi and M. Toyota, Tetrahedron Lett., 2009, 50, 4888;
2. (b) Stoichiometric conditions: A. Hibi, K. Takeda, and M. Toyota, Heterocycles, 2009, 77, 173.
3. M. Saeki and M. Toyota, Tetrahedron Lett, 2010, 51, 4620.
4. (a) Isolations: T. Sakan, F. Murai, S. Isoe, S. B. Hyeon, and Y. Hayashi, J. Chem. Soc. Jpn., 1969, 90, 507;
5. (b) Recent total syntheses: H. Nagata and K. Ogasawara, Tetrahedron Lett, 1999, 40, 6617;
6. (c) D. Bouyssi, N. Monteiro, and G. Balme, Tetrahedron Lett, 1999, 40, 1297;
7. (d) K.-W, Liang, M. Chandrasekharam, C.-L. Li, and R.-S, Liu, J. Org. Chem, 1998, 63, 7289.
8. Reviews: (a) D. H. Grayson, Nat. Prod. Rep, 2000, 17, 385;
9. (b) A. Nangia, G. Prasuna, and P. B. Rao, Tetrahedron, 1997, 53, 14507.
10. Satisfactory analytical data were obtained for all new compounds. Compound 8: IR (neat) 1745 and 1730 cm-1. 1H NMR (400 MHz, CDC13) δ 5.74 (1H, br s), 4.35 (1H, ddd, J = 11.2, 7.6 and 3.2 Hz), 4.28 (1H, dddd, J = 11.2, 7.2, 2.8, and 0.4 Hz), 3.78 (3H, s), 3.08-3.01 (1H, m), 2.79-2.70 (1H, m), 2.22-2.06 (2H, m), 1.87 (3H, br s), and 1.77-1.69 (1H, m). 13C NMR (100 MHz, CDCl3) δ 171.1, 168.3, 137.0, 131.4, 67.7, 66.9, 53.1, 41.1, 38.1, 29.4, and 14.8. LRMS m/z 210 (M+). HRMS calcd for C11H14O4 (M+) 210.0892, found 210.0890. Compound 11: IR (neat) 1713 cm-1 1H NMR (400 MHz, CDCl3) δ 5.55 (1H, br s), 4.35-4.20 (2H, m), 3.80-3.50 (1H, m), 3.00-2.84 (1H, m), 2.74 (1H, dddd, J = 16.4, 9.2, 4.8, and 2.4 Hz), 2.14-1.98 (2H, m), 1.81 (3H, br s), and 1.72-1.61 (1H, m). LRMS m/z 152 (M+). HRMS calcd for C9H12O2 152.0837, found 152.0836.
11. H. Ohta, T. Kobori, and T. Fujiwara, J. Org. Chem, 1977, 42, 1231.