A New Class of Ligands for Aqueous Lanthanide-Catalyzed Enantioselective Mukaiyama Aldol Reactions

摘要

The development of aqueous methods to generate enantiopure β-hydroxy carbonyl compounds is an important goal because these subunits compose many bioactive compounds, and the ability to synthesis these groups in water has environmental and cost benefits. In this communication, we report a new class of ligands for aqueous, lanthanide-catalyzed, asymmetric Mukaiyama aldol reactions to synthesize chiral β-hydroxy ketones. Furthermore, we use luminescence-decay measurements to unveil mechanistic information regarding the catalytic reaction via changes of water-coordination number. The precatalysts presented here yielded β-hydroxy carbonyls from aliphatic and aryl substrates with outstanding syn:anti ratios and enantiometric excesses of up to 49:1 and 97%.