Cycloaddition behavior of unsymmetric cyclopentadienone. Peri- and regio-selectivities

Abstract

An asymmetrically substituted cyclopentadienone, 2-methoxycarbonyl-5-methyl-3,4-diphenylcyclopentadienone 1a, was synthesized and cycloadditions of compound 1a with various unsaturated compounds involving conjugated medium-ring polyenes were investigated. The cycloaddition behavior was analyzed by frontier molecular orbital (FMO) theory, indicating that the reactivity, stereo- and regio-selectivities observed are entirely consistent with the FMO predictions.

References

1. (a) K. Harano, M. Yasuda and K. Kanematsu, J. Org. Chem., 1982, 47, 3736; (b) M. Yasuda, K. Harano and K. Kanematsu, J. Am. Chem. Soc., 1981, 103, 3120; (c) J. Org. Chem., 1981, 46, 3836; (d) 1980, 45, 2368; (e) K. Harano, M. Yasuda, T. Ban and K. Kanematsu, ibid., 1980, 45, 4455; (f) T. Ban, Y. Wakita and K. Kanematsu, J. Am. Chem. Soc., 1980, 102, 5415; (g) K. N. Houk and R. B. Woodward, ibid., 1970, 92, 4145; (h) 1970, 92, 4143.
2. (a) K. Fukui, Kagaku Hanno to Densi no Kido (Chemical Reactions and Electron Orbitals), Maruzen, Tokyo, 1976; (b) I. Fleming, Frontier Orbitals and Organic Chemical Reactions, Wiley, London, 1976.
3. (a) S. Greenfield and K. Mackenzie, J. Chem. Soc., Perkin Trans. 2, 1986, 1651; (b) R. J. Atkins and G. I. Fray, Tetrahedron, 1979, 35, 1173.
4. D. M. White, J. Org. Chem., 1974, 39, 1951.
5. The long-range ¹³C–H couplings (³J) between the bridge carbonyl carbon and the exo and endo methylene protons of trinorboren-7-one have been reported to be 0 and 5–9 Hz, respectively: R. Y. S. Tan, R. A. Russel and R. N. Warrener, Tetrahedron Lett., 1979, 5031.
6. M. Mori, A. Hayamizu and K. Kanematsu, J. Chem. Soc., Perkin Trans. 1, 1981, 1259.
7. (a) K. Harano, K. Uchida, M. Izuma, T. Aoki, M. Eto and T. Hisano, Chem. Pharm. Bull., 1988, 36, 2312; (b) T. Jikyo, M. Eto and K. Harano, Tetrahedron, 1997, 53, 12415; (c) M. Eto, K. Uchida and K. Harano, ibid., 1994, 50, 13395; (d) G. I. Fray and A. W. Oppenheimer, Chem. Commun., 1967, 599.
8. R. Sustmann, Tetrahedron Lett., 1971, 2717, 2721.
9. (a) K. B. Astin and K. Mackenzie, J. Chem. Soc., Perkin Trans. 2, 1975, 1004; (b) P. H. Mazzocchi, B. Stahly, J. Dodd, N. G. Rondan, L. N. Domelsmith, M. D. Rozeboom, P. Caramella and K. N. Houk, J. Am. Chem. Soc., 1980, 102, 6482; (c) K. Mackenzie, Tetrahedron Lett., 1974, 1203; (d) S. Inagaki, H. Fujimoto and K. Fukui, J. Am. Chem. Soc., 1976, 98, 4054.
10. (a) P. V. Alston, R. M. Ottenbrite and D. D. Shillady, J. Org. Chem., 1973, 38, 4075; (b) P. V. Alston and R. M. Ottenbrite, ibid., 1975, 40, 1111; (c) P. V. Alston and D. D. Shillady, ibid., 1974, 39, 3402.
11. M. Sodupe, R. Rios, V. Branchadell, T. Nicholas, A. Oliva and J. J. Dannemberg, J. Am. Chem. Soc., 1997, 119, 4232 and references cited therein.
12. H. F. Allen and J. A. Vanallan, J. Am. Chem. Soc., 1950, 72, 5165.