Enantioselective Addition of Thiols to Imines Catalyzed by Thiourea–Quaternary Ammonium Salts Hong-Yu Wang Jia-Xing Zhang Dong-Dong Cao Gang Zhao 10.1021/cs400594e.s002 https://acs.figshare.com/articles/journal_contribution/Enantioselective_Addition_of_Thiols_to_Imines_Catalyzed_by_Thiourea_Quaternary_Ammonium_Salts/2369968 Asymmetric phase-transfer catalysis was first applied to the synthesis of chiral N,S-acetals by using amino acid-based bifunctional thiourea-ammonium salt catalysts. The reaction could be performed on the gram scale to give up to 93% ee and 99% yield with a catalyst loading as low as 0.1 mol % within 5 min. 2013-10-04 00:00:00 Imines Catalyzed Thiol Enantioselective Addition Ammonium ee synthesis 5 min 0.1 gram scale SaltsAsymmetric catalysi mol Thiourea bifunctional chiral catalyst loading