Abstract
We developed an enantioselective organocascade Michael/Henry reaction in the presence
of a bifunctional organocatalyst to construct chiral polyfunctionalized 3,4-dihydro-2H-thiopyrano[2,3-b]quinolines. The resulting optically active products with three contiguous stereocenters,
one quaternary and two tertiary, were obtained in moderate to good yields and with
good to excellent enantioselectivities. Remarkably, the resulting products were readily
converted into polyfunctionalized optically active furo[2′,3′:4,5]thiopyrano[2,3-b]quinoline, 3,4-dihydro-2H-thiopyrano[2,3-b]quinoline 1-oxide and 2,3-dihydro-4H-thiopyrano[2,3-b]quinolin-4-one derivatives.
Key words
Domino reaction - Michael addition - Henry reaction - thiopyranoquinolines - polyheterocycles
- cascade reaction