Structures of a pair of diastereomeric salts of ephedrine and di­chloro-substituted cyclic phosphoric acid

(1) (R)-(+)-4-(2,6-Dichlorophenyl)-2-hydroxy-5,5-dimethyl-1,3,2-dioxaphosphorinane 2-oxide (1S,2R)-(-)-alpha-[(1-methylamino)ethyl]benzyl alcohol, (-)-C10H16NO+.(+)-C11H12Cl2O4P-, M(r) = 476.335, monoclinic, P2(1), a = 10.063(1), b = 8.206(1), c = 14.856(1) angstrom, beta = 104.84(1)-degrees, V = 1185.8 (2) angstrom3, Z = 2, D(x) = 1.334 Mg m-3, Mo K-alpha radiation (graphite monochromator), lambda = 0.71073 angstrom, mu(Mo K-alpha) = 0.3689 mm-1, F(000) = 500, T = 130 K, final R = 0.053, wR = 0.056 for 3504 observed unique reflections and 281 variables. (2) (S)-(-)-4-(2,6-Dichlorophenyl)-2-hydroxy-5,5-dimethyl-1,3,2-dioxaphosphorinane 2-oxide (1R,2S)-(-)-alpha-[(1-methylamino)ethyl]benzyl alcohol hydrate, (-)-C10H16NO+.(-)-C11H12Cl2O4P-.H2O, M(r) = 494.351, orthorhombic, P2(1)2(1)2(1), a = 6.502(1), b = 11.393 (1), c = 32.739 (1) angstrom, V = 2425.2 (4) angstrom3, Z = 4, D(x) = 1.354 Mg m-3, Mo K-alpha radiation (graphite monochromator), lambda = 0.71073 angstrom, mu-(Mo K-alpha) = 0.3660 mm-1, F(000) = 1040, T = 130 K, final R = 0.055, wR = 0.059 for 4225 observed unique reflections and 265 variables. For both (1) and (2), the phosphorinane ring is in the usual chair conformation and the ephedrine is in an extended form. The crystal packing of (1) can be regarded as chains parallel to the b axis consisting of phosphorinane anions and ephedrine cations linked by hydrogen bonds. In the crystal packing of (2), which can also be regarded as chains parallel to the b axis, the solvent water molecules are incorporated in the hydrogen-bonding pattern between the phosphorinane and ephedrine ions