Purification Methods
The amine is mixed with aqueous 10N NaOH and extracted with toluene. The extract is washed with saturated aqueous NaCl, dried over K2CO3, and transferred to fresh K2CO3 until the solution is clear, and is filtered. The filtrate is distilled. If a short column packed with glass helices is used, the yield is reduced but a purer product is obtained. [Ingersoll Org Synth 25 89 1945, Snyder & Brewster J Am Chem Soc 71 291 4165 1949, Cope et al. J Am Chem Soc 71 3931 1949.] The (-)-picrate has m 140-141o from EtOH). The racemate [1126-71-2] has b 88-89o/16mm, 92-94o/30mm, 194-195o/760mm, d4 0.908. [Beilstein 13 III 2392.]