544-47-8

white crystalline powder

Identification of organic acids.

Crystallise the salt from conc HCl by addition of water. Dry it in a vacuum over P2O5. Also crystallise it from EtOH, wash the crystals with EtOH, then Et2O to give the lower melting form m 177-178o. By evaporating the filtrate and washings to a quarter of the volume and adding an equal volume of Et2O the higher melting form m 201-203o is obtained. [Harvey & Jensen J Org Chem 28 470 1963, Beilstein 6 III 1639, 6 IV 2778.]