Researches on the constitution of physostigmine. Pt. 3 / by Arthur H. Salway.

  • Salway, Arthur H. (Arthur Henry)
Date:
[1913?]
Catalogue details

Licence: Public Domain Mark

Credit: Researches on the constitution of physostigmine. Pt. 3 / by Arthur H. Salway. Source: Wellcome Collection.

    5/12 (page 1990)
    It was observed, however, that the nitro-group of 3-nitro-p-tolyl- acrylic acid (VI) was more readily attacked by reducing agents than the cinnamyl residue, so that the first product of the reaction was not a substituted propionic acid (VII), but 3-amino-p-tolyl- acrylic acid (VIII), which by further reduction then became con¬ verted into 13-3-ami no-’p-tolylpropioriic acid (IX) : Me/ \cii:cil*coji —> Me/ \ch:cii*co9h; —> \_/ “ \ _/ NOo NH2 (VI.) (VIII.) Me/ /cII,-CII2-C02H nh; (IX.) Under no condition of reduction investigated by the author was it possible to reduce the 3-nitro-p-tolylacrylic acid (VI) without affecting the nitro-group. Experimental. I. Preparation of 2:5-Dimethylindole from m-4.-Xy Udine. In order to ascertain whether m-4-xylidine could be converted into 2 :5-dimethylindole, a quantity of the former was acetylated, and the resulting acetyl derivative (m. p. 129°; b. p. 170°/10 mm.) heated for a short time at 250—300° with an equal weight*of dry sodium ethoxide in the absence of air. After the vigorous reaction which ensued had subsided, water was added, and the mixture distilled in a current of steam. The first portion of the distillate contained xylidine, but subsequently a solid compound began to pass over into the receiver. This was collected separately, and purified by crystallisation from a mixture of benzene and light petroleum, when glistening leaflets melting at 114° were obtained (Found, 0 = 82*7; H = 7-7. C10HnN requires 0=82-8; TI = 7-6 per cent.). This substance readily gave the pine-shaving colour reaction typical of indoles, and wTas evidently identical with 2 :5-dimethyl¬ indole (compare Raschen, Annalen, 1887, 239, 227). The yield of the latter amounted to 40 per cent, of the acetoxylidide employed in the reaction. 2: i-Xylylsuccinamic Acid (III, p. 1989). For the preparation of this compound six parts of w-4-xylidine were added to a solution of five parts of succinic anhydride in hot chloroform, and the mixture allowed to cool. In a very short time colourless, slender needles of the succinamic acid were deposited, the yield amounting to 80 per cent, of the theoretical. The sub-