Crystal Structure of (±)-2-14-(4-Chlorophenoxymethy1)-phenoxylpropionic Acid

The crystal structure of (±)-2-[4-(4-chlorophenoxymethyl)phenoxy]propionic acid has been determined by direct methods using three-dimensional X-ray diffraction data. The crystals are triclinic, P1, Z 2, a 9·345(2), b 12·602(2), c 6·741(1) Å, α 101·37(1), β 97·42(1), γ 101·75(1)°. The structure refined to give a final R 0·084 for 2172 observed reflections. The acid molecules form centrosymmetric hydrogen bonded cyclic dimers [O ··· 0, 2 · 619(4) Å] about a centre of symmetry in the cell. The oxopropionic acid side chain has a synplanar-synplanar (carbonyl) conformation while the planar p-chlorophenoxymethyl substituent in the p-position has a synclinal orientation relative to the primary phenoxy residue.