Stereoselective synthesis of 2,6-syn-dimethyl-tetrahydropyran derivatives, important segments of marine polycyclic ethers, by unique insertion of the methyl group.
Treatment of 6-methyl-tetrahydropyran derivatives, which have a 1'-mesyloxy group at the C2-side chain, with Me(3)Al effected stereoselective insertion of a methyl group at the C2-position to give 2,6-syn-dimethyl-tetrahydropyran derivatives. This reaction proceeds via removal of the mesyloxy group, 1,2-hydride shift, and stereoselective insertion of a methyl group into the resulting oxonium ion.
Maemoto
Michihiro
M
Department of Chemistry, Faculty of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan.
Kimishima
Atsushi
A
Nakata
Tadashi
T
D002384:Catalysis; D004852:Epoxy Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D004987:Ethers; D008386:Marine Biology; D015394:Molecular Structure; D011714:Pyrans / Q000737:chemistry*; D013237:Stereoisomerism
D004852:Epoxy Compounds; D004987:Ethers; D011714:Pyrans