Hydrochloric Acid → Sodium 4-hydroxyphenylglycolate

Participants

Reaction Steps

Sodium hydroxide solution (50% w/w, ca 650 ml) was added dropwise over about one hour to a stirred mixture of phenol (1.098 kg), aqueous glyoxylic acid (50% w/w solution, 720 ml) and water (3 l) at 15° C. until a pH of 10.5 had been reached. The reaction mixture was then stirred and tested at 35° C. for 3 hours. The solution was adjusted to pH7 with concentrated hydrochloric acid and extracted at 35° C. with methyl isobutyl ketone to remove excess phenol. The aqueous solution was adjusted to pH2 with concentrated hydrochloric acid and continuously extracted in a counter-current extractor with ethyl acetate at an organic to aqueous flow rate of 1 to 1.

Provenance & Evidence