Highly Enantioselective Sulfur-Michael Addition (SMA) Of 1,4-Dicarbonyl But-2-enes

Organocatalysis have received great attention in asymmetric synthesis for its enzyme mimic, metal-free, atomatically economic and low toxic characters. In this thesis, the catalytic effects of the cinchona alkaloid-derived thiourea bifunctional catalysts as organocatalysts to asymmetric sulfa-Michael addition were investigated. The addition of tert-butyl mercaptan to 1, 4-dicarbonly but-2-enes including (E)-4-oxo-4-arylbutenamides and (E)-4-oxo-4-arylbutenones is developed to synthesize a series of chiral sulfur-substitutedα-stereogenic amides and ketones with high regioselectivity and enantioselectivity (ee values up to 97%).