Catalytic enantioselective synthesis of chiral γ-butyrolactones
Akira Yanagisawa1, Naoyuki Kushihara, Kazuhiro Yoshida
1Department of Chemistry, Graduate School of Science, Chiba University, Chiba 263-8522, Japan. ayanagi@faculty.chiba-u.jp
Abstract:
A tandem catalytic asymmetric aldol reaction/cyclization of β,γ-didehydro-γ-lactones with aldehydes was achieved using chiral tin dibromide as a chiral precatalyst and sodium alkoxide as a base precatalyst. Optically active trans-β,γ-disubstituted γ-butyrolactones were selectively obtained in moderate to high yields with up to 99% ee from γ-aryl-substituted β,γ-didehydro-γ-butyrolactones and bulky aliphatic aldehydes.
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