Further syntheses of p-hydroxphenylethylamine / by George Barger and George Stanley Walpole.

  • Barger, George, 1878-1939
Date:
[1909?]
Catalogue details

Licence: Public Domain Mark

Credit: Further syntheses of p-hydroxphenylethylamine / by George Barger and George Stanley Walpole. Source: Wellcome Collection.

    4/8 (page 1723)
    0-1326 gave 0’2836 C02 and 0'0712 H20. C = 58'2; H = 5'9. 0'0869 „ 10‘2 c.c. N2 (moist) at 19° and 762 mm. N = 13’5. C10H12O3N2 requires C = 578; H = 5'8; N = 135 per cent. The nitro-compound thus obtained was reduced, the crude amino- compound diazotised, and the resulting solution was concentrated until it contained about 30 per cent, of sulphuric acid, and heated to 140°. ^'Hydroxyphenylethylamine was then extracted by amyl alcohol and isolated as the dibenzoyl derivative (m. p. 169—170°), but none of the intermediate compounds were characterised. p-N it ro phenyl ethyl amine, N02*C6H4*CH2,CH2,NH2. This substance is readily obtained, mixed with its isomerides, when benzylidenephenylethylamine, CH2Ph*CH2*NICHPh (melt¬ ing at about 70°; prepared by warming the components), is nitrated in sulphuric acid solution by the addition of the calculated quantity of potassium nitrate. On diluting with water and removing, by steam distillation, the benzaldehyde formed, a yellow oil remains, which, on acetylation and benzoylation, yields the derivatives (melting respectively at 142° and 162°), which have been described above. The benzoyl derivative was hydrolysed by heating with ten times its weight of concentrated hydrochloric acid to 170° for four hours. p-Nitrophenylethylamine was thus obtained as a yellow syrup, which could not be crystallised, and was readily soluble in most organic solvents. It absorbed carbon dioxide from the air, forming a crystalline carbonate. The hydrochloride forms leaflets, melting at 214°, and was analysed: 0-2141 gave 0'1522 AgCl. Cl = 17*6. C8H10O2N2,HCl requires Cl = 17'5 per cent. II.—Synthesis of p-Hydroxyphenylethylamine from Anisoldehyde. The ^'ro^hoxyphenylpropionic acid required was prepared according to the same method as that employed by Perkin and Robinson (Trans., 1907, 91, 1079) for the preparation of 3: 4-di- methoxyphenylpropionic acid. Anisaldehyde (100 grams) was condensed with ethyl acetate (245 grams) by means of finely-divided sodium (245 grams). After one hour, 102 grams of potassium hydroxide, dissolved in methyl alcohol, were added; after removal of the alcohol by distillation, the solution was treated with 3000 grams of 2J per cent, sodium amalgam. The resulting methoxyphenylpropionic acid was crystal¬ lised from water; yield 46 grams, melting point 104°,