Phenylglycine-o-carboxylic acid

It is an important dyestuffs intermediate. It condenses with chloroethanoic acid to give phenylglycine-o-carboxylic acid for the synthesis of indigo. It can be diazotized and used as a first component in azo-dyes it condenses also with chloroanthraquinones to give intermediates for anthraquinone dyes. 

Phenylglycine-o-carboxylic acid. In a 750 ml. round-bottomed flask, fitted with a reflux condenser, place 14 g. of anthranilic acid (Section IV,170), 10 g. of chloroacetic acid, 20 g. of anhydrous sodium carbonate and 200 ml. of water. Reflux the mixture for. 3 hours, then pour into a beaker, cool, render shghtly acid with concentrated hy dro-chloric acid, and allow to stand overnight. Filter off the crude acid and wash it with water. Recrystalhse from hot water with the aid of a little decolourising carbon, and dry the acid at 100°. The yield of phenyl-glycine-o-carboxyhc acid, m.p. 208°, is 12 g. 

Phenylglycine-o-carboxylic acid [612-42-0] M 195.2, m 208°. Crystd from hot water (charcoal). 

Double cyclization of the phenylglycine o-carboxylic acids 611 (R = H) with acetic or benzoic anhydride by heating gave the mesoionic oxazolones 612 and 613, respectively, which upon treatment with BF3 Et20 gave 615... 

P-Phenylethyl alcohol, 812,816 Phenylethylene, 1015,1024 a-Phenylethylamine, 560, 566 P-Phenylethy,amine, 560, 567,569 Phenylethylbarbituric acid, 1003,1005 P-Phenylethyl bromide, 283 P-Phenylethyl iodide, 288 Phenylglycine-o-carboxylic acid, 980 Phenylglyoxal, 866 Phenylhydrazine, 635, 636 hydrochloride, 636, 637 Phenylhydrazine acetate reagent, 343, 721 ... 

T2 gms. caustic potash are dissolved in 100 c.cs. water, and to this are added 9-4 gms. chloroacetic acid and 13-6 gms. anthranilic acid. The solution is warmed on a water bath under a reflux for 2 hours at 60°— 80°. Hydrochloric acid is then added to neutralise. The phenylglycine-o-carboxylic acid separates out after standing and is filtered off and recrystallised from water. A further yield can be obtained by evaporating the filtrate. 

Phenylglycine-o-carboxylic acid from anthranilic acid... 

The fusion mixture from (b) is dissolved in 2 liters water at 80°C., and a vigorous stream of air is passed through the solution until no more indigo is formed in a filtered test sample when shaken with air. The precipitated dye is filtered off, washed with water, boiled with dilute hydrochloric acid to remove all of the lime, filtered again, washed thoroughly with water, and finally dried in a steam heated oven. The yield is 12 to 12.5 grams, or 80 to 82 per cent of the theoretical amount based on the phenylglycine-o-carboxylic acid. 

Indoxylcarboxylic acid from phenylglycine-o-carboxylic acid. 324... 

To a 2-L flask equipped with a condenser were added 137 g anthranilic acid (1 mol), 94.5 g chloroacetic acid (1 mol), and 1 L water the mixture was heated for 3 h. On cooling, crystals of phenylglycine-o-carboxylic acid were separated out. These were filtered off and recrystallized from hot water to give 1000 g of such acid. 

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