Action of sodium amalgam on methylene ethers / by Arthur H. Salway.

  • Salway, Arthur Henry.
Date:
1910
Catalogue details

Licence: In copyright

Credit: Action of sodium amalgam on methylene ethers / by Arthur H. Salway. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

    4/9 (page 2414)
    uu no account was given in the previous communications, has now been isolated in sufficient quantity to render its complete examination possible. The purified compound was found to possess the properties of a phenol and of a carboxylic acid, and gave analyses corresponding with the empirical formula C10H]2O4. It is evident that the pro- duction of such a compound from 3-methoxy-4: 5-methylenedioxy- cinnamic acid (I) can only be explained by the simultaneous reduction of the aliphatic side-chain and the substitution of a hydroxyl group for the methyleuedioxy-complex. The constitution of the resulting compound would therefore appear to be represented by one of the two formulse A and B : oh <V>h:ch.cosh 2 °\/ OMe (I.) ho/\ch2-ch2-co2h \y OMe (A.) or HOs J oh2-oh2-co2h OMe (B.) In order to decide between these formulse, the substance was converted by means of methyl sulphate into a dimethoxyphenyl- propionic acid, which melted at 61—62°. The dimethoxy-acid corresponding with B, namely, B-3: 4-dimethoxyphenylpropionic acid, melts, according to Tiemann and Nagai (Ber., 1878, 11, 653), at 97°, whilst the 3: 5-dimethoxy-acid corresponding with A does not appear to have been hitherto described. Formula B is thus shown to be inadmissible, and consequently A most probably repre- sents the constitution of the substance under examination. Positive evidence in support of this conclusion was obtained by converting the dimethoxypropionic acid into the corresponding dimethoxy- benzoic acid by oxidation with alkaline permanganate solution. The product of oxidation melted at 180—181°, and was found to be identical with 3: 5-dimethoxybenzoic acid. It is thus shown that in the reduction of 3-methoxy-4: 5-methylenedioxycinnamic acid (I), the normal reaction is accompanied by a secondary change involving the disruption of the methylenedioxy-complex and the formation of j8-5-hydroxy-3-methoxyphenylpropionic acid (III), according to the scheme on p. 2415. It was next deemed of interest to ascertain whether other methylene ethers are capable of undergoing a similar change, and accordingly piperonylacrylic acid (IV) was subjected to the action of sodium amalgam. In this case, also, it was found that reduction