It separates in the form of small rose-red crystals, which decompose on boiling with water.
This method is adopted for substances which decompose at their boiling-points under ordinary pressure, and, generally, when it is desirable to work at a lower temperature.
In this method of preparation it is found that the secondary alcohols decompose more readily that the primary alcohols of the series, and when sulphuric acid is used, two phases are present in the reaction, the first being the building up of an intermediate sulphuric acid ester, which then decomposes into sulphuric acid and hydrocarbon: C2H 5 OH->C 2 H 5 HSO 4 ->C 2 H 4 +-H 2 SO 4.
Alkalis decompose it into picro-podophyllic acid and picro-podophyllin, minute traces of both of which occur in a free state in the rhizome.
When strongly heated they decompose, forming fatty acids, nitrogen peroxide and nitrogen.
It crystallizes in small needles, which are readily soluble in water, and on heating, decompose at about 102° C., with liberation of nitrogen, chlorine and oxygen.