Dimethyl Sulfate → Methyl 4-amino-5-chloro-2-hydroxybenzoate

Beteiligte Stoffe

Reaktionsschritte

A solution of 4-amino-5-chloro-2-hydroxybenzoic acid (1.88 g, 0.010 mole) in absolute methanol (20 ml) was treated with 25% sodium methoxide/methanol (2.16 g, 0.010 mole), stirred for 30 minutes, and concentrated in vacuo. The solid residue was taken up in anhydrous acetone (30 ml), treated with dimethyl sulfate (1.64 g, 0.013 mole) and refluxed for 2 hours. The resultant solution was diluted with water (100 ml), and the precipitate was filtered, washed with water, and dried exhaustively in vacuo to afford 1.75 g (87%) of the title compound as fine colorless needles. The material was recrystallized from ethyl acetate/hexane; mp 138°-139° C.

Herkunft & Nachweise