1. (a) Qian-Cutrone, J.; Gao, Q.; Huang, S.; Klohr, S. E.; Veitch, J. A.; Shu, Y.-Z. J. Nat. Prod. 1994, 57, 1656–1660.
2. (b) Whyte, A. C.; Gloer, K. B.; Gloer, J. B.; Koster, B.; Malloch, D. Can. J. Chem. 1997, 75, 768–772.
3. Highly periselective [2,3]wittig rearrangements on dihydrofuran and dihydropyran rings
4. This reaction is helpful for our final goal, the asymmetric syntheses of 1–4, because recently we found that the asymmetric oxyselenenylation of 2,3-dihydrofuran and subsequent oxidation afforded 6 in an enantioselective manner, which could give an optically active alcohol 7 by this rearrangement.
5. The dienes subjected to Diels–Alder reaction with 12 was as follows. (a) 1,1-Dimethoxy-3-trimethylsiloxy-1,3-butadiene: Banville, J.; Brassard, P. J. Chem. Soc., Perkin Trans. 1 1976, 1852–1856. (b) 1,3-Bis(trimethylsiloxy)-5,5-dimethylcyclohexa-1,3-diene: Ibuka, T.; Mori, Y.; Aoyama, T.; Inubushi, Y. Chem. Pharm. Bull. 1978, 26, 456–465. (c) 1,3-Dimethoxy-1-trimethylsiloxy-1,3-butadiene: Savard, J.; Brassard, P. Tetrahedron 1984, 40, 3455–3464. Only 1,3-dimethoxy-1-trimethylsiloxy-1,3-butadiene did not react with 12.