Dedicated to Prof. Guo-Qiang Lin for his 80th birthday.
A series of optically active 3,3′-pyrrolidinyl-dispirooxindole derivatives containing
a CF3 moiety have been efficiently constructed through asymmetric catalytic cascade reactions
catalyzed by cinchona-derived bifunctional squaramide catalyst, bearing four contiguous
stereogenic centers, two of which are vicinal spiro-stereocenters. Additionally, a
wide range of substituted products were achieved with moderate to high yields (up
to 99% yield) and excellent stereoselectivities (up to >20:1 dr for all cases and up to 99% ee).
Key words
organocatalysis - dispirooxindole - cascade reactions - four contiguous stereogenic
centers - new substrates