Sodium Hydroxide → (2-Hydroxyphenyl)acetic acid

Participants

Reaction Steps

`Isopar M` (500 ml), (2-chlorophenyl)acetic acid (51.3 g, 0.3M), copper II sulphate hexahydrate (2.88 g, 10 mM) and sodium hydroxide pellets (84 g, 2.1M) were changed to a 1.5 litre hastalloy vessel equipped with a stirrer and condenser. The temperature of the vessel was increased from ambient using an oil bath, while stirring the reaction mixture. The oil bath was maintained at between 210° C. and 220° C. for 6 hours and then heating was ceased and the vessel was allowed to cool to ambient temperature. Water (500 ml) was added (exothern) and the reaction mixture was stirred for a further 30 minutes. After filtering off some insoluble material (about 600 mg) the phases were separated and the upper organic phase set aside (480-490 ml). The aqueous phase was acidified to pH1 (by test paper) by adding 36% hydrochloric acid (125-155 ml, exothern), and then extracted with isopropyl acetate (2×250 ml). The combined isopropyl acetate extracts were evaporated at 60° C. and about 20 mm Hg on a rotary evaporator to give (2-hydroxyphenyl)acetic acid as brown solid (44-45 g, purity by gas chromatography 94-99%, yield 93-96%).

Provenance & Evidence