An organocatalytic asymmetric sulfa-Michael addition of thiols to β-trifluoromethyl β,β-disubstituted (E)-enones in the presence of 10 mol% of a cinchona alkaloid-derived thiourea catalyst provides direct and simple access to chiral trifluoromethyl tertiary thioethers in high yields and up to 76% ee.
Key words
asymmetric catalysis - enones - Michael additions - organocatalysis - thiols - sulfides