Methylamine → 1-[4-Fluoro-2-(methylamino)phenyl]ethanone

Beteiligte Stoffe

Reaktionsschritte

A mixture of a solution of methylamine in industrial methylated spirit (33% w/w; 120 ml), industrial methylated spirit (60 ml), 2'-chloro-4'-fluoroacetophenone (51.6 g) and copper powder (0.75 g), was charged to a pressure vessel and heated to 90° for 2 hours. After cooling in an ice bath to 30° the mixture was transferred to a second vessel, heated at 50° and then a solution of sodium sulphide nonahydrate (2.88 g) in water (30 ml) added. The mixture was heated to reflux with stirring for 10 minutes and then filtered. Water (300 ml) was added to the filtrate and the solution heated to reflux. Hydrochloric acid (5M; 90 ml) was added to the hot solution and the mixture heated to reflux for a brief period. The reaction mixture was cooled to ambient temperature and aqueous sodium hydroxide solution (5M; 30 ml) added. The mixture was extracted with dichloromethane (600 ml) and then further extracted with dichloromethane (200 ml). The combined dichloromethane extracts were dried (magnesium sulphate) and evaporated in vacuo to give a crude brown oil. The oil was distilled in vacuo (b.p. 90°, 1 mmHg) to give 4'-fluoro-2'-(methylamino)-acetophenone, m.p. 52°-53°.

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