Communication
Chem. Commun., 2009, 7294 - 7296, DOI: 10.1039/b919535a
Highly enantioselective hetero-Diels–Alder reactions between Rawal
s diene and aldehydes catalyzed by chiral dirhodium(II) carboxamidatesYudai Watanabe, Takuya Washio, Naoyuki Shimada, Masahiro Anada and Shunichi Hashimoto
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], Rh2(S-BPTPI)4, proceeded cleanly and gave, after treatment with acetyl chloride, the corresponding dihydropyranones in up to 99% ee.
