A novel recyclable prolinamide-derived ionic-liquid-supported organocatalyst of asymmetric cross-aldol reactions in aqueous medium has been developed. In its presence, aromatic aldehydes react with cyclic or linear ketones to afford chiral aldol adducts in moderate to high yields and with ex-

The undesirable side‐processes responsible for the fast deactivation of primary amino acid derived organocatalysts in asymmetric aldol reactions are identified. A new ionic‐liquid‐supported (S)‐valine‐/(S)‐α,α‐diphenylserinol‐derived catalyst (9) is designed on the basis of these results and exhibits much better recyclability in asymmetric syn‐aldol reactions between hydroxyacetone and aldehydes. Furthermore, this catalyst appeared to be useful for the stereoselective synthesis of the naturally occurring 1(3H)‐isobenzofuran‐1‐one scaffold through an asymmetric syn‐aldol/lactonization cascade reaction.

A simple and efficient synthesis of enantiomerically pure (1S,2S)-1,2-di(pyridin-2-yl)- and (1R,2R)-1,2-di(pyridin-4-yl)-ethane-1,2-diamines from commercial picolinaldehyde or isonicotinaldehyde and 2,2'-((1S,2S)-1,2-diaminoethane-1,2-diyl)diphenol (HPEN) via a stereospecific diaza-Cope rearrangement has been developed. Diamine (R,R)-2b was readily converted to novel diastereomeric ionic group-supported bis-prolinamides (R,S)-1b and (R,R)-1b which appeared to be efficient organocatalysts of asymmetric cross-aldol reactions in aldehyde/aldehyde, ketone/ketone or ketone/aldehyde reagent systems under neat conditions to afford corresponding aldols in high yields and with up to 99% ee. Furthermore, catalyst (R,S)-1b could be reused over 15 times in the same or similar catalytic reactions exhibiting close to original activity and a high level of stereoinduction.

A novel recyclable threonine-derived ionic-liquid-supported organocatalyst of asymmetric cross-aldol reactions has been developed. In its presence, aromatic aldehydes react with hydroxyacetone, methoxyacetone and 2-butanone to afford the corresponding syn-aldol products in moderate to high yields with excellent diastereo-(syn/anti up to 96:4) and enantio-selectivity (up to 95 % ee), which was retained over five recycling experiments.

Mono-and Bis-Aldol Reactions in the Presence of Water. -A novel recyclable prolinamide-derived ionic-liquid-supported organocatalyst of asymmetric cross-aldol reactions in aqueous medium is developed. In its presence, aromatic aldehydes react with cyclic or linear ketones to afford chiral aldol adducts in moderate to high yields and with excellent diastereo-and enantioselectivities that do not tend to decline over ten recycles of the catalyst. Furthermore, this catalyst allows a highly enantioselective synthesis of linear bis-aldols in aqueous medium. -(KUCHERENKO, A. S.; GERASIMCHUK, V. V.; LISNYAK, V. G.; NELYUBINA, Y. V.; ZLOTIN*, S. G.; Eur. J. Org. Chem. 2015, 25, 5649-5654, http://dx