Deoxyephedrine - mandelic acid diastereomers

Resolution of mandelic acid with (-)(R)-deoxyephedrine in 95% ethanol produ ces essentially nondiscriminating unsolvated binary mandelate salts. (R)-de oxyephedrinium (R)-mandelate (I) is orthorhombic, P2(1)2(1)2(1), a = 8.076( 2) Angstrom, b = 8.926(3) Angstrom, c = 23.242(15) Angstrom, V = 1675.3(14) Angstrom(3). Z = 4. (R) -deoxyephedrinium (S)-mandelate (II) is monoclinic , P2(1), a = 16.061(14) Angstrom, b = 8.902(8) Angstrom, c = 19.585(20) Ang strom, beta = 111.76(8)degrees, V = 2600(4) Angstrom(3), Z = 6 With three i on pairs comprising the asymmetric unit. The principle interionic interacti ons are ribbon-like chains of salt-bridge hydrogen bonds which associate pr otonated secondary ammonium ions with carboxylates in I and II along crysta llographic screw axes with a six-atom repeating unit H-N+-H ... O-C--O [C-2 (2)(6)]. The (R)-mandelate additionally shows intraion hydrogen bonding and the (S)-mandelate shows interanion hydrogen bonding. Solubilities (in 95% ethanol), fusion points and heats of fusion indicate essentially no diaster eometric discrimination. From acetone, the (S)-mandelate salt forms a efflo rescent hemiacetone solvated binary phase (III), triclinic, P1, a = 10.869( 9) Angstrom, b = 10.838(13) Angstrom, c = 17.138(18) Angstrom, alpha = 90.3 2(9)degrees, beta = 91.34(8)degrees, gamma = 108.20(8)degrees V = 1917(4) A ngstrom(3), Z = 4. Ions form hydrogen bonded chains similar to those in II; acetones are unassociated. In I, columns form with the polar hydrogen bond ed chains at the core and nonpolar aryl rings radiating and interdigitating adjacent columns. Packing in II and III produces bilayers of alternating p olar and nonpolar regions, with acetones of III in the nonpolar regions.