Mixed Aromatic Acyloin Condensations with Recombinant Benzaldehyde Lyase: Synthesis of α‐Hydroxydihydrochalcones and Related α‐Hydroxy Ketones

Recombinant benzaldehyde lyase (BAL), expressed and purified from E. coli strain JM‐109, was used to catalyze the condensation of a series of methoxybenzaldehydes and phenylacetaldehyde in the synthesis of α‐( R )‐hydroxydihydrochalcones. Enantiomerically pure 1‐hydroxy‐1,3‐diphenylpropan‐2‐ones and o ‐anisoin were also obtained as products of the BAL reaction. The R absolute configurations of chiral centers were determined by CD spectroscopy. α‐( R )‐Hydroxydihydrochalcones and 1‐hydroxy‐1,3‐diphenylpropan‐2‐ones are valuable synthons for chemoenzymatic syntheses of flavonoids. This is the first synthesis of α‐( R )‐hydroxydihydrochalcones by a microbial enzyme.