A series of novel carbohydrate-derived thioureas were synthesized and examined as catalysts for the asymmetric Michael addition of symmetrical 1,3-dicarbonyl compounds, including dimethyl malonate, to several trans-β-nitrostyrenes. High enantioselectivities (up to 94% ee) as well as high yields (up to 98%) were attained using a bifunctional organocatalyst bearing a cinchona-based alkaloid unit.
Disclosed is a process of carrying out a Michael reaction with recovery of the catalyst, where a compound of formula (1):
is reacted with a compound of formula (2):
in the presence of a catalyst of formula (4):
where the compounds of formulae (1) and (2) undergo a Michael reaction.