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Collectively, these alkaloids occur mainly in the Papaveraceae, Ranunculaceae,. Berberidaceae, and Menispermaceae; Papaver somniferum (opium poppy) Collectively, these alkaloids occur mainly in the Papaveraceae, Ranunculaceae,. Berberidaceae, and Menispermaceae; Papaver somniferum (opium poppy) Collectively, these alkaloids occur mainly in the Papaveraceae, Ranunculaceae,. Berberidaceae, and Menispermaceae; Papaver somniferum (opium poppy) Collectively, these alkaloids occur mainly in the Papaveraceae, Ranunculaceae,. Berberidaceae, and Menispermaceae; Papaver somniferum (opium poppy)
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  8 Dr. C. R. A. Wright^s Contributions to the [Nov. 16^ and there may be considerable likelihood thatconditions explained orrendered probable under the statical theory would have some correspond-ing explanation or confirmation under any true theory by which the statical might come to be superseded. With a view to brevity, how- ever, and to the avoidance of putting forward speculations perhaps partly rash, though, I think, not devoid of realsignificance, I shall not at pre- sententer on details of these considerations, but shall leave them with merely the slight suggestion now offered, and with the suggestion men- tioned in an earlier part of the present paper, of thequestion whether in an extremely thin lamina of gradual transition from a liquid to its own gas, at their visible face of demarcation, conditions may not exist in a stable state having a correspondence with the unstable conditions here theoretically conceived, II,   Contributions to the History ofthe Opium Alkaloids. — Part III.^^ By C. R. A. Wright, D.Sc, Lecturer on Chemistry in St. Mary's Hospital Medical School. Communicated by Dr. H. E. RoscoE. ReceivedJuly 21, 1871. § 1 . Action ofHydriodic Acid onGodeia in presence of Phosphorus, In Parts I. and II. of these researches the action of hydrobromic acid on codeia and its derivatives has been partially investigated ; and as the action of this acid appears to be in some respects similar to, but in others different from, that of hydrochloric acid, it appeared to be of interest to examine the action of hydriodic acid also. Some preliminary experiments on this subject made two orthree years ago in conjunction with the late Dr. A. Matthiessen, showed that when codeia is boiled with a large excess ofstrong hydriodic acid, no appreciable quantityof methyl iodide is evolved even after some hours' treatment ; a brown tarry mass containing much free iodine was produced, but at the time nothing fit for analysis was obtained from this ; since then, Dr,Matthiessen and Mr. Burnside ^ have corroboratedthe non-formation of methyl iodide under these circumstances. If, however, phosphorus be added simultaneously with the hydriodic acid, so asto prevent the accumulation of free iodine, methyl iodide is evolved at 100° and upwards in quantity close upon that required for the equation Codeia. Morphia. C,3 H,, NO3 + HI= CH3 1 -f C,, H,9 NO3 hitherto, however, no body of this latter formula has been isolated from the products of the reaction, thesubstances ultimately formed being derived from a basecontaining H^ more than morphia. The hydriodic acid was obtained in the 'first instance by the action of * Proc. Roy. Soc. vol.xix. p. 71.  ISyi.] History of the Opium Alkaloids, 9 hydric sulphide on iodine and water : in the dilute acid thus got, iodine was dissolved, and the whole digested at a Tery gentle heat with phosphorus, more iodine solution being added from time to time ; finally the whole was distilled several times from potassium iodide. A colourless acid of sp. gr. 1 -7-1  755 and containing 50-55 per cent, of HI, was thus obtained, and preserved colourless by keeping a stick of phosphorus in the bottle. The codeia used in these experiments was part of a further supply most libe- rally presented by Messrs. Macfarlane,of Edinburgh, On heating on the water-bath a mixture of 10 parts codeia, 30 to 50 of this acid, and 1 of phosphorus, the evolution of methyl iodide is noticed in a fewminutes ; simultaneously the liquid becomes brown, indicating the separation of free iodine ; after two or three hours the brown colour dis- appears, and the evolution of methyl iodide ceases. If the liquid be heated to gentle ebullition,at first the same effects ensue, but more quickly ; the resulting product, however, varies in composition according to the tempe- rature at which the reaction was efi^ected. In one experiment 55 grammes of codeiayielded by condensation 22*5 grammes of methyl iodide, the theoretical yield being 24 '6 from crystallized codeia, 0^^ H^, NO3, H^O ; hence upwards of 90 per cent, ofthe theoretical yield was obtained. In order to prove the elimination of -f^ part of the carbon in the form of methyl iodide, 4*3045 grammes of codeia, dried at 140°-150° C, was heated to gentle ebullition with 30 grammes of 55 per cent, hydriodic acid and about 2 of phosphorus ; the vapours evolved were passed through a flask to condense aqueous vapour, and then through a combustion-tube filled with red-hot lead chromate, the CO^ produced being absorbed in theusual way, an aspirator being attached at the far end so asto create a diminished pressure throughout the apparatus, and thus guard against loss ofmethyl-iodide vapour by leakage at any of the nume- rous corks and joints*. After three hours a current of pure oxygen was led through the apparatus, to sweep outthe last traces ofmethyl-iodide vapour from the flasks and ensure the perfect combustion of deposited carbonaceous particles. 4*3045 grms. codeia thus gave 0*617 grm.COg. 0*3720 grm. codeia, burnt in theusual way, gave 09 830 CO^. Found. Calculated^ (A) Percentage of carbon evolved as CEI33*91 4*013(B) „„ in codeia used . 72*0772*241 Eatio of A to B ««««»«ã»««ã«»ã 3*91 ^ 1 72*07 18*2 4*013 1 72*241 18 In another experiment, not carriedto a complete conclusion, the COg col- lected represented3*7 per cent, of the codeiaused. The methyl iodide produced was found, after washing with water, dry- * This device may be applied withadvantage to the ordinary processes for combus- tion, blowing out of the tube as wellas loss by traces of leakage being thus avoided.  10 Dr. C. R. A. Wright^s Contributions to the [Nov. 16, ing over Ca Cl^, and distillation, to be free from traces of dissolved phos- phorus, to boilat 42°-45° C, and to correspond in every respect withthe ordinary methyl iodide. If the reaction with hydriodic acid takes place on thewater-bath, the resulting product appears to have the composition Cgg H^g I^ N^ O^^, 4HI ; but if the mixturebe heated to gentle ebullition throughout, the tempera- ture not being allowed to exceed 110^-115° from loss of aqueous fluid by evaporation, the substanceobtained contains the elements of two molecules of water less, = Cgg Hgg Ig N^ O^q, 4HI ; whilst if the mixture be rapidly boiled, so that by evaporation the boiling-point rises to 130° and upwards, the ultimate product contains less oxygen than this last body, being Cgg Hggig N^Og, 4HI. These three formulse might each be halved; but inasmuch as compounds containing not less than Cgg have been got from these products by simple treatments, the higher formulae are more probable. All three substances are, while moist, colourless tars, drying at 100° to brittle waxy-looking masses, not fusing at 100° when perfectly dry ; they aresoluble in hot water, a decomposition being thereby produced ; while moist they appear to absorb oxygen with avidity, rapidly becoming yellow ororange. They are also extremely hygroscopic ; and from the high per- centage of iodinecontained, the ease with which they decompose on heat- ing, and the difficultly combustible carbon left, their analysis is a matter of some considerable difficulty. From all these circumstances combined, the numbers obtained do notalways accord quite as closely as might be expected in the case of crystalline and easily purified substances. To obtain the compound Ogg Hgg I^ N^ O^^, 4HI, 10 parts of codeia, 30 of 55 per cent, hydriodic acid, and 1 of phosphorus may be heated on the water-bath for three to four hours, at the end of which time the evolution of methyl iodide has entirely ceased : by filtering the syrupy hot liquid through asbestos to separate particles of amorphous phosphorus and addi- tion of a little water when cold, a colourless tar is precipitated, which soon sets to a hard brittle mass ; this is broken up and thoroughly washed with water to separate the phosphorus acids produced simultaneously, and finally freed from moisture as far as possible by pressure between filter paper, and dried at 100°. The same body may also be obtained by dissolving the srcinal substance in slightly warm water, precipitating with sodium carbonate, and extraction ofthe mass thus thrown down with ether and agitation of the first portions ofthe ether extract with hydriodic acid : the tar thus got is identicalin all respects with the srcinal substance. After drying at 100° thefollowing numbers were obtained* : (A) Prepared by first method : 0-3785 grm. gave 0*588 CO, and 0-173 Hg O. 0-359 grm. gave 0*2535 Agl. * All combustions given in this paper were made with lead chromate and oxygen ; and theiodine determinations by boiling with nitric acid and silver nitrate.  1871.] History of the Opium Alkaloids, 11 (B) Prepared by etherprocess : 0-357 grm. gave 0-5655 00^ and 0-165 H^ 0. 0-2635grm. gave 0-1895 Agl. (C) Another specimen prepared by etherprocess : 0-316 grm. gave 0493 CO^ and 0-135 H, O. 0-2865 grm. gave 0-2025 Ag. Found. Calculated. A c H I N O 68 90 4 12 816 90 762 5619242-59 4-70 3977 2-9210*02 C,3H,J,N,0,„4HI 1916 100-00 A. 42-36 5-08 38-16 B. 43-20 5-14 38-87 c 42-54 4-75 38-19 Mean. 42-70 4-99 38-41 The falling short in the percentage of iodine found in these specimens is readily accounted for by the action of the water which necessarily adheres to the tarry product got by either of the above processes ; it will be sub- sequently shown that by the action of water on this body the elements of HI are removed from it. This compound is apparently formed by the reaction Codeia hydriodate. New body. 4(C,,H,, NO3, HI)+14HI=4CH3l + I, + C,JI,J,N,0,,, 4HL The iodine thus set free is of course reconverted into HI by the action of the phosphorus, a mixture of phosphorous and phosphoric acids being thereby produced. The reaction 3I, + P, + 6H,0 = 2H3P03-f6HI requires for 50 grms. ofcodeia 3*45grms. of phosphorus to be converted into phosphorous acid ; whilst the equation 5I,+P,4-8H2 = 2113 PO^+SHI requires 2*07 grms. to be converted into phosphoric acid. In one experi- ment 2*8 grms. of phosphorus, as nearly as could be estimated, were found to have become converted into the mixture of the two acids, 50 grms. of codeia havingbeenemployed. On attempting to procure the free base C^g Hgg I^ Ng O^^ from thehydrio-dategot as above, by precipitation with sodium carbonate, a snow-white mass was obtained containing,besides a small quantityofthe desired base (solublein ether), a large quantityof two otherbasesderived from this one (but sparingly soluble in ether). The description of the products thus got will be given in a subsequent section. By treating codeia with hydriodic acid and phosphorus as above de- scribed, but at atemperature of gentle ebullition not rising above 115°, a
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