Organocatalysts derived from 1,1′-Bi-2-naphthol (BINOL) and amino acids have been developed and synthesized via a simple straightforward two-step reaction sequence using chiral BINOL and α-amino acids as starting materials. These catalysts are used to catalyze the direct asymmetric syn-aldol reactions of various aromatic aldehydes and hydroxyacetone. Owing to a favorable Z-enamine conformer of the hydroxyacetone and various non-bonded interactions, the syn-product was the favored product. Reactions involving aromatic aldehydes with substituents in the 2-position showed slight enantioselectivity.
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