Chiral Amino Diol Derivatives as New Modular Organocatalysts for the Enantioselective α-Chlorination of Cyclic β-Keto Esters

Highly modular chiral amino diol derivatives have been used as organocatalysts in the enantioselective alpha-chlorination of cyclic beta-keto esters. Optimization of the catalyst structure and the reaction conditions has allowed the synthesis of optically active alpha-chlorinated products with high enantioselectivities (up to 96% ee) using inexpensive commercially available N-chlorosuccinimide (NCS) as the chlorine source under mild conditions.