Rigg. — Montan Wax. 287 



The first step (a) took place without difficulty ; in step (b) the a hydroxy 

 acid was readily obtained, but all attempts to prepare the pure unsaturated 

 acid were unsuccessful, and step (c) could not therefore be attempted. 



Le Seur,* in the degradation of stearic acid to palmitic, also experienced 

 considerable difficulty in the isolation of pure unsaturated acid (A a oleic 

 acid). He only obtained a 10-per-cent. yield. 



The following is a brief description of the compounds isolated and the 

 experiments made in connection with the degradation of montanic acid 

 to cerotic : — 



Brommontanic Acid. — Hell and Sadomsky's methodt was used for the 

 preparation of this compound. 6 grams of ethyl montanate were ground 

 with 0-19 grams of dried red phosphorus, which had been previously freed 

 from phosphorous acid by repeated washing with water. Anhydrous 

 bromine was now added drop by drop to the mixture contained in a flask. 

 There was no violent action such as Le Seur records in the case of the 

 formation of bromstearic acid. The contents of the flask were then 

 warmed on the water bath for two hours under a reflux condenser. The 

 condenser was now removed, and the excess of bromine allowed to escape. 

 The molten mass thus obtained was poured into cold water. The crude 

 brommontanic acid was melted twice in fresh water to decompose any 

 acid bromide. 



The crude brommontanic acid was then crystallized from acetic acid 

 and motor spirit. By this means a pure compound was obtained, which 

 melted at 75° C. The melting-point did not change on further crystal- 

 lization. 



Brommontanic acid crystallizes from acetic acid in colourless hexagonal 

 plates. It is easily soluble in acetic acid and motor spirit ; the yield 

 obtained after two crystallizations was 60 per cent, of the theoretical. 



Calc. for C 28 H 55 Br0 2 . Found. 



Br. = 15-90 15-81 



Attempts to remove hydrobromic acid from brommontanic acid by 

 means of pyridine, quinoline, and a concentrated solution of caustic potash 

 did not result in the production of the unsaturated acid, as had been 

 expected. 



The hydroxy acid could easily be obtained, mixed with the unsaturated 

 acid, by the action of 30-per-cent. alcoholic potash on brommontanic acid, 

 but all attempts to remove water from it by means of ortho-phosphoric 

 acid which had previously been heated to 200° were unsuccessful. 



In conclusion, the author wishes to thauk Professor Easterfield for 

 suggesting this subject for research, and also for much practical advice, 

 without which the writer could not have undertaken this investigation. 



*»• 



* Journ. Chem. Soc. 1904, p. 1708. 

 t Berichte, vol. 24, 1891, p. 2390. 



