Cinchonine and thiourea

In this viewpoint, we discuss the seminal work contributed by Dixon, who reported the first use of a bifunctional cinchona-derived thiourea organocatalyst for the enantioselective conjugate addition of malonate esters to nitroalkenes. Since then, this class of catalysts has been extensively utilized in a variety of fundamental transformations. We also highlight here some of the representative studies performed since the publication of this milestone work in 2005.