Purify it via the semicarbazone (m 179,5-180.5o from 90% MeOH) and regenerate it by steam distilling a mixture of 13.1g of semicarbazone, 22g of phthalic anhydride and 45mL of H2O. After collecting 300mL of distillate, the latter is extracted with Et2O. The dried extract (MgSO4) gives on evaporation 8.4g of ketone b 100-101.5o/15mm. The oxime has m 76.5-77.5o ( 7 9o from MeOH) and the iso-oxime has m 138-139o [Ruzicka et al. Helv Chim Acta 32 548 1949.] It has also been repeatedly sublimed at 0.05-0.1mm pressure. [Blomquist et al. J Am Chem Soc 74 3639, 3645 1952, Beilstein 7 III 110, 7 IV 62.]
