The direct aldol reaction between methylglyoxal (40% aqueous solution) or phenylglyoxal monohydrate and ketones or aldehydes is catalyzed by N-tosyl-(S
a)-binam-l-prolinamide to afford the corresponding chiral γ-oxo-β-hydroxy carbonyl compounds, mainly as anti isomers with enantioselectivities up to 97%.
Key words
methylglyoxal - organocatalysis - aldol - prolinamide - aqueous conditions