The first example of a chiral Lewis acid-catalyzed enantioselective hetero-Diels-Alder (HDA) reaction between 1-dimethylamino-3-silyloxy-1,3-butadiene (Rawal's diene) and aldehydes is described. The cycloaddition reaction under the influence of 1 mol% of dirhodium(II) tetrakis[N-benzene-fused-phthaloyl-(S)-piperidinonate], Rh-2(S-BPTPI)(4), proceeded cleanly and gave, after treatment with acetyl chloride, the corresponding dihydropyranones in up to 99% ee.
机构:
Hokkaido Univ, Fac Pharmaceut Sci, Kita Ku, Kita 12,Nishi 6, Sapporo, Hokkaido 0600812, Japan
Ritsumeikan Univ, Res Org Sci & Technol, 1-1-1 Noji Higashi, Kusatsu 5258577, JapanMusashino Univ, Fac Pharm, Nishikyo Ku, 1-1-20 Shinmachi, Tokyo 2028585, Japan