2,3-Diaryl-3-hydroxypropionic acid intermediates in the synthesis of threo forms of 1,2-diaryl-1,3-propanediols.

Racemic threo-3-hydroxy-2,3-diphenylpropionic acid, C15H14O3, (I), crystallizes from ethyl acetate as a conglomerate of separate (+)- and (-)-crystals. The geometries of (I) and its methyl ester are compared. Reduction of (I) gives threo-1,2-diphenyl-1,3-propanediol. The synthesis of threo forms of 1,2-diaryl-1,3-propanediols via 2,3-diaryl-3-hydroxypropionic acids is discussed.