1871.] 



On the History of the Opium Alkaloids. 



371 



coloured the liquid, it was submitted to distillation. Only a small portion 

 came over below 40°; the thermometer rose rapidly to 180°, and nearly 

 the whole of the bromine-compound distilled at 184° to 188°. This sub- 

 stance is amylene bromide, C 5 H 10 Br 2 ; Wurtz gives the boiling-point of this 

 body at about 180°. The portion therefore boiling at 35° is mainly 

 amylene. 



Exactly similar results were obtained from the portion boiling at 65° to 

 70°. This, from its boiling-point, may be either C 6 H 12 or C 6 H u , or a 

 mixture of both. Bromine disappears instantly on adding it to the care- 

 fully cooled liquid, and on distillation by far the greater portion is found 

 to have combined with the halogen. The bromide thus obtained distils 

 with slight decomposition about 195°. Pelouze and Cahours found that 

 hexylene bromide, C 6 H 12 Br 2 , boiled at 192° to 198°. 



We are at present engaged in the further investigation of this subject, 

 and hope shortly to lay our results before the Royal Society. 



III. " Contributions to the History of the Opium Alkaloids. Part 

 I. — On the Action of Hydrobromic Acid on Codeia/" By 

 C. It. A. Wright, D.Sc. Communicated by Professor Roscoe 

 F.R.S. Received February 6, 1871. 



It has been shown by the late Dr. A. Matthiessen, in conjunction with 

 the writer *, that when codeia is heated with a large excess of strong hy- 

 drochloric acid the following reactions successively take place : — 

 Codeia. Chlorocodide. 



C 18 H 2l N0 3 + HC1=H 2 O + C M H 20 CI N0 2 . 



Chlorocodide. Apomorphia. 



C 18 H 20 CI N0 2 = CH 3 CI + C„ H 17 N0 2 . 



It appeared of interest to examine the action of hydrobromic acid under 

 similar circumstances, and for this purpose Messrs. Macfarlane, of Edin- 

 burgh, with their wonted liberality, put a considerable quantity of pure 

 codeia at the writer's disposal. 



The aqueous hydrobromic acid employed was obtained by the action of 

 H 2 S on Br in presence of water, and subsequent rectification over pulver- 

 ized KBr; it was free from S0 4 H 2 and other sulphur compounds, had a 

 sp. gr. of about 1*5, and contained about 48 per cent, of H Br. 



When codeia is heated with from three to six times its weight of this 

 acid, either on a water-bath or to gentle ebullition over a flame, the liquid, 

 which at first produces no precipitate with solution of carbonate of soda, 

 gradually darkens in colour, and acquires the property of yielding a dense 

 white precipitate with this reagent. No appreciable quantity of methyl 



* Proc. Koy. Soc. vols. xvii. p. 460, xviii. p. 83. 



