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The potential of β-alkoxy α-keto amides as pronucleophiles in the enantioselective Mannich type reaction with p-nosyl imines is presented. The proper combination of β-alkoxy α-keto amides and a squaramide-based Brønsted base catalyst produced highly enantioenriched Mannich adducts, which may be transformed into functionalized amino diols., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first enantioselective direct cross-aldol reaction of α-keto amides with aldehydes, mediated by a bifunctional ureidopeptide-based Brønsted base catalyst, is described. The appropriate combination of a tertiary amine base and an aminal, and urea hydrogen-bond donor groups in the catalyst structure promoted the exclusive generation of the α-keto amide enolate which reacted with either non-enolizable or enolizable aldehydes to produce highly enantioenriched polyoxygenated aldol adducts without side-products resulting from dehydration, α-keto amide self-condensation, aldehyde enolization, and isotetronic acid formation., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)