126 THE SIMPLER NATURAL BASES 



Isobutylamine hydrochloride does not melt at 160, as stated in 

 Beilstein, but at 177-178 (Thorns and Thiimen [1911]). 



The platinichloride forms golden yellow crystals, very soluble in 

 alcohol and in water, decomposing at 224-225 and melting at 230- 

 232. 



Isolation of isoamylamine from putrid horse meat. The material 

 had undergone putrefaction anaerobically for eight to ten days at 37. 

 The proteins were coagulated, the filtrate was evaporated to a syrup, 

 mixed with sand and extracted with acetone. After distilling off the 

 acetone, hydrochloric acid was added to the residue, which was washed 

 with chloroform to remove fatty acids, etc., and then rendered alkaline 

 and again extracted with chloroform. After evaporation of the solvent 

 the base was distilled and converted into the crystalline oxalate. 



Isoamylamine hydrochloride forms deliquescent crystals ; the hydro- 

 bromide is non-deliquescent. The acid oxalate C 5 H 13 N, H 2 C 2 O 4 is ob- 

 tained by mixing ethereal solutions of oxalic acid and of the base ; 

 m.p. 169 ; it slowly loses amylamine at 100 and should be dried in 

 vacuo. 



The platinichloride forms golden yellow leaflets, readily soluble in 

 hot water. 



Isolation and Separation of Putrescine and Cadaverine. 



Both bases are very common in putrefaction. They are not 

 readily volatile with steam, nor can they readily be extracted from 

 aqueous solution by ether or by chloroform. They can be precipi- 

 tated by phosphotungstic acid, and after treatment with silver nitrate 

 and baryta they are found in the lysine fraction (see above). From 

 this they can be precipitated by mercuric chloride in alcoholic solution, 

 or they may be precipitated directly by this reagent, as was done by 

 Brieger, without previous use of phosphotungstic acid. He precipi- 

 tated both bases from an alcoholic extract of a putrefaction mixture 

 by means of alcoholic mercuric chloride and afterwards fractionally 

 crystallised the platini- and aurichlorides (putrescine aurichloride 

 is the less soluble in water). It is, however, more convenient to 

 separate the hydrochlorides, that of putrescine being but little soluble 

 in 96 per cent, alcohol, whereas the corresponding cadaverine salt 

 dissolves readily. 



From urine Udranszky and Baumann [1888, I, 1889] separated 

 both bases as dibenzoyl compounds by shaking with benzoyl chloride in 

 sodium hydroxide solution ; this process is quantitative even in a I : 

 10,000 solution of the base. The benzoyl derivatives are washed with 



