Asymmetric Intramolecular Rauhut-Currier Reaction and Its Desymmetric Version via Double Thiol/Phase-Transfer Catalysis.

An asymmetric intramolecular Rauhut-Currier reaction of linear bis(enones) has been achieved via double activation catalysis of thiols and phase transfer substances, furnishing both enantioenriched cyclohexene and cyclopentene derivatives (up to 95% ee). Furthermore, the desymmetric version of prochiral substrates was developed under similar catalysis, producing the frameworks bearing an additional tertiary or even quaternary stereogenic center with moderate to excellent diastereo- and enantioselectivity (up to 95% ee, >19:1 dr).