Dissolve it in alkali, extract with ether (discard), then the aqueous phase is acidified with hydroxylamine hydrochloride, and the nitro compound is collected and fractionally distilled under reduced pressure. [Pearson & Dillon J Am Chem Soc 75 2439 1953, Beilstein 1 H 101, 1 III 202, 1 IV 173.]
