An efficient synthesis of chiral isoquinuclidines by Diels-Alder reaction using Lewis acid catalyst

作者：Hirama Masafumi; Kato Yuji; Seki Chigusa; Nakano Hiroto; Takeshita Mitsuhiro; Oshikiri Noriko; Iyoda Masahiko; Matsuyama Haruo^*

来源：Tetrahedron, 2010, 66(38): 7618-7624.

DOI：10.1016/j.tet.2010.07.026

• Alkaloid
• 1,2-Dihydropyridine
• Isoquinuclidine
• Diels-Alder reaction
• Lewis acid catalyst
• Diastereoselectivity

The Diels-Alder reaction of 1,2-dihydropyridine derivatives (1-phenoxycarbonyl-1,2-dihydropyridine 1 or 1-methoxycarbonyl-1,2-dihydropyridine 4) with N-acryloyl (1S)-2,10-camphorsultam (15)-2 (or N-acryloyl (1R)-2,10-camphorsultam (1R)-2) in the presence of Lewis acid, such as titanium tetrachloride, zirconium tetrachloride, and hafnium tetrachloride afforded the endo-cycloaddition product, 2-azabicyclo[2.2.2]octane derivatives in good yields with excellent diastereoselectivity. The absolute stereochemistry assignment of the endo-cycloaddition product (15)-5a starting from N-acryloyl (15)-2,10-camphorsultam (1S)-2 has been established to be (1S,4R,7S) and the reaction mechanism was proposed.

• 出版日期2010-9-18