Dimethylformamide → 3-Methoxy-4-propoxy-5-nitrobenzaldehyde

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-nitrovanillin (10 g), propyl iodide (25 g), potassium carbonate (10 g) and N,N-dimethylformamide (200 ml) is stirred at 100° C. for 24 hours. After cooling, water (500 ml) is added to the reaction mixture, followed by extraction with ethyl acetate (200 ml). The extract solution is washed with water, dried and, then, distilled off under reduced pressure. The residue is purified by means of a silica gel column chromatography (hexane: ethyl acetate=2:1-1:1) to afford 4-propoxy-3-methoxy-5-nitrobenzaldehye (6 g) as a pale yellow oily product. This product is dissolved in acetone (200 ml), and potassium permanganate (18 g) is added to the solution. The mixture is stirred at room temperature overnight. To the reaction mixture are added ethanol (50 ml), water (50 ml) and acetone (200 ml). The whole mixture is stirred for two hours, and filtered off. The filtrate is concentrated under reduced pressure. Precipitating crystals are collected by filtration to give 3-methoxy- 5-nitro-4-propoxy benzoic acid (2.2 g) as colorless crystals. This product is recrystallized from a mixture of ethanol and water to give colorless needles, m.p. 121°-123° C.

Provenance & Evidence