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A convenient and novel oxazol-5-one addition to nitrostyrenes is reported. The reaction is catalyzed by tertiary amines and yields the corresponding adducts with total regio- and diastereoselectivity. The addition exclusively takes place at the C-2 position of oxazol-5-ones, furnishing diastereopure N,O-aminals.

The first examples of highly enantioselective organocatalytic Mannich reactions of ferrocenecarbaldehyde are disclosed. The reaction is catalyzed by simple amino acids and gives access to β-arylamino-β-ferrocenylketones in high yields and with up to 99% ee.

Financial support from the MEC (Projects CTQ2004-00808/BQU, CTQ2007–62771/BQU and Consolider INGENIO 2010 CSD2007-00006), from the Generalitat Valenciana (GRUPOS05/11, GV05/144, GV/2007/142) and the University of Alicante.

A convenient and novel oxazol-5-one addition to nitrostyrenes is reported. The reaction is catalyzed by tertiary amines and yields the corresponding adducts with total regio- and diastereoselectivity. The addition exclusively takes place at the C-2 position of oxazol-5-ones, furnishing diastereopure N,O-aminals.

Organocatalysts 1, derived from L-proline and (1S,2R)-cis-1-aminoindan-2-ol or (R)-1-aminoindane, are evaluated as promoters in the direct asymmetric aldol reaction between ketones and aromatic aldehydes in the presence of water and under solvent-free reaction conditions. L-Prolinethioamides 1c and 1d exhibited higher enantioselectivity than the corresponding prolinamides 1a and 1b in the model aldol reaction between cyclohexanone and 4-nitrobenzaldehyde in the presence of 4-nitrobenzoic acid as cocatalyst. In particular, L-prolinethioamide 1d (5 mol%), derived from L-proline and (R)-1-aminoindane, is shown as the most efficient organocatalyst studied promoting the direct aldol reaction of cycloalkyl, alkyl, and α-functionalized ketones with aromatic aldehydes in the presence of water and under solvent-free reaction conditions employing only 2 equivalents of nucleophile. Generally, anti-aldol products are obtained in high yields and excellent diastereo- and enantioselectivities (up to >98/2 anti/syn, up to 98% ee). Solvent-free conditions give slightly higher dr and ee than using water as solvent. In addition, organocatalyst 1d can be easily recovered by extractive work-up and reused. Prolinethioamide 1d (5 mol%) in combination with 4-NO2C6H4CO2H (5 mol%) is also a very effective organocatalytic system for the asymmetric solvent-free intramolecular Hajos-Parrish-Eder-Sauer-Wiechert reaction with comparable or higher levels of enantioselectivity (up to 88% ee) to other reported catalysts in organic solvents. Financial support from the MEC (Projects CTQ2004-00808/BQU, CTQ2007–62771/BQU and Consolider INGENIO 2010 CSD2007-00006), from the Generalitat Valenciana (GRUPOS05/11, GV05/144, GV/2007/142) and the University of Alicante.