Preparation of 2-(4-aminophenoxy)acetic acid
20 g of 4-nitrophenoxyacetic acid are dissolved in a slight excess of dilute ammonia and the solution is poured in a thin stream into a vigorously stirred, boiling solution of 7 molecular equivalents (one in excess) of ferrous sulfate (FeSO4 · 7H2O) in 2.5 parts of water. The reaction takes place according to the equation:
Small portions of concentrated aqueous ammonia are then immediately added, stirring the solution vigorously after each addition and continuing the addition of ammonia until the solution remains definitely alkaline pH after stirring and boiling. The mixture is boiled 5 minutes, making certain that the reaction remains alkaline, and is filtered hot through a large Buchner funnel which, with the suction flask, has previously been warmed to prevent cracking. The precipitate of iron hydroxides is washed with a little amount of hot dilute ammonia solution and the filtrate concentrated in vacuum until the ammonium salt filtrate of the 2-(4-aminophenoxy)acetic acid begins to separate owing to the salting-out action of the ammonium sulfate present. The mixture is then heated until the salt dissolves and treated with an excess of acetic acid, yielding 15.7 g of 2-(4-aminophenoxy)acetic acid which precipitate almost at once. The 2-(4-aminophenoxy)acetic acid crystallizes with one molecule of water of crystallization.
An advanced laboratory manual of organic chemistry, M. Heidelberger, 46-48, 1923
2-(4-aminophenoxy)acetic acid, (4-Aminophenoxy)acetic acid, 2298-36-4, 4-aminophenoxyacetic acid, (p-Aminophenoxy)acetic acid, Acetic acid, (4-aminophenoxy)-, GIFGMEWQGDEWKB-UHFFFAOYSA-N, 23557-77-9, PubChem16282, ChemDiv2_003232, AC1L3V3Z, AC1Q1H3Y, Oprea1_812941, SCHEMBL655820, (4-Amino-phenoxy)-acetic acid, CHEMBL368851, Acetic acid, (p-aminophenoxy)-, NIOSH/AF3520000, CTK4F0628, MolPort-001-815-617, Acetic acid,2-(4-aminophenoxy)-, BB_SC-1486, HMS1378C20, KST-1A2983, AC1Q5253, ALBB-008749, NSC36983, ZERO/001282, EINECS 218-947-5, ANW-47293, AR-1A5423, BBL013866, NSC-36983, SBB001635, STK500580, AKOS000103919, MCULE-5505108288, AJ-09152, AK-34236, AN-50663, BR-34236, EN002293, KB-14651, KB-88730, LS-10980, ST057195, AB0023591, M B 2754, ST2416095, TC-136038, AF35200000, FT-0679420, W4673, S-5691, I01-8106