Reaktion #9721

Reaktionsgleichung

hydrochloric acid

ethyl[4-(acetyloxy)-2-methylphenoxy]acetate

intermediate 6

ethyl[4-(acetyloxy)-2-methylphenoxy]acetate

sodium ethoxide

→

solution

ethyl(4-hydroxy-2-methylphenoxy)acetate

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture as cooled to 22° C.

Vorschrift

A solution of ethyl[4-(acetyloxy)-2-methylphenoxy]acetate (intermediate 6, 148 g) in ethanol (1300 ml) was treated with sodium ethoxide (41.3 g) and the mixture heated to 45° C. for 2.5 hours. The mixture as cooled to 22° C. and concentrated hydrochloric acid added to give a neutral (pH 7) solution. The resulting mixture was concentrated and the residue dissolved in a mixture of t-butylmethyl ether, water and brine. The organic layer was separated, washed with brine and dried over sodium sulfate and filtered. The filtrate was concentrated to give a brown solid which was further purified by precipitation from a solution in dichloromethane (100 ml) on addition of cyclohexane (710 ml) to give the title compound as a brown solid.

Quelle