Abstract
The enantioselective synthesis of a seven-membered enone compound,
the key intermediate of our previous synthesis of the inside-outside framework of
13-oxyingenol in racemic form, was achieved by using asymmetric
cyclopropanation and reductive deoxygenation as key steps.
Key words
13-oxyingenol - asymmetric cyclopropanation - chiral aza-semicorrin
ligand - reductive deoxygenation - intramolecular aldol
reaction
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This asymmetric synthesis of seven-membered
enone (-)-7 had a low yield in
comparison with our previous approach in racemic form, possibly
because of the small reaction scale. The
detailed experimental procedures for the seven-membered enone (±)-7
6 in multigram scale are given
in the experimental section.