(+ -)-THREO-3-HYDROXY-2,3-DIPHENYLPROPANOIC ACID METHYL-ESTER/

The crystal structure of methyl (+/-)-threo-3-hydroxy-2,3-diphenylprop anoate, C16H16O3, has been determined. In the crystal, the phenyl grou p at the chiral alpha-C atom and the hydroxy group at the chiral beta- C atom are in the energetically preferred trans conformation. The tors ion angle O-C beta-C(a)lpha-C-phenyl is 175.8(2)degrees. The H atoms a t the chiral C atoms are also in an antiperiplanar arrangement. Pairs of molecules are linked via a pair of weak intermolecular hydrogen bon ds between hydroxyl H and carbonyl O atoms. The IR spectrum verifies t he presence of this hydrogen bond. The dihedral angle between the leas t-squares planes through the phenyl rings is 53.0 (1)degrees. The dist ance between the alpha and beta chiral C atoms is 1.530(3) Angstrom. T he bond distances and angles of the molecule are as expected.