A catalytic asymmetric Mannich-type reaction of alkenyl trichloroacetates with aldimines was achieved using SEGPHOS·AgOTf as the chiral precatalyst and N,N-diisopropylethylamine as the base precatalyst in the presence of 2,2,2-trifluoroethanol. Optically active β-amino ketones with up to >99% ee were syn-selectively obtained in moderate to high yields via the in situ generated chiral silver enolates.

A catalytic asymmetric O‐nitroso aldol reaction of alkenyl trifluoroacetates with nitrosoarenes was achieved by using QuinoxP*·AgOAc [(R,R)‐QuinoxP* = (–)‐(R,R)‐2,3‐bis(tert‐butylmethylphosphino)quinoxaline] as the chiral precatalyst and N,N‐diisopropylethylamine as the base precatalyst in the presence of methanol. Optically active α‐aminooxy ketones with up to 99 % ee were regioselectively obtained in moderate to high yields by the in situ generated chiral silver enolates.

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Catalytic Enantioselective Mannich-Type Reaction via a Chiral Silver Enolate. -All reaction products are isolated with 98% diastereoisomeric excess. -(YANAGISAWA*, A.; LIN, Y.; MIYAKE, R.; YOSHIDA, K.; Org. Lett. 16 (2014) 1, 86-89, http://dx.doi.org/10.1021/ol403075u ; Dep. Chem., Grad. Sch. Sci., Chiba Univ., Inage, Chiba 263, Japan; Eng.) -U. Scheffler 22-028