Purification Methods
It is best to prepare it freshly from the hydrochloride (see below). Dissolve the hydrochloride (123.5g) by adding it slowly to an ice-cold mixture of H2O (500mL), K2CO3 (276g) and Et2O (200mL) and stirring rapidly. The Et2O layer is separated, the aqueous layer is extracted with Et2O (100mL), the combined Et2O layers are dried (MgSO4), evaporated and the residual oil is distilled through a glass helices packed column (70x1.2cm). The yield is 19g (22%). [Glickman & Cope J Am Chem Soc 67 1020 1945, Chaplin & Hunter J Chem Soc 1118 1937, Hunter & Ludwig Methods Enzymol 25 585 1972.]
