Water → 2-Methyl-6-nitrobenzaldoxime

Beteiligte Stoffe

Reaktionsschritte

A solution of 274 g (2.6 mol) of n-butyl nitrite (97% pure) and 300 g (2.0 mol) of 3-nitro-o-xylene (97% pure) in 750 ml of dimethylformamide is cooled to from −55 to −60° C., and a solution of 522 g (4.56 mol) of potassium tert-butoxide in 750 ml of dimethylformamide is added dropwise at this temperature, over a period of 2.5 hours. The color of the solution changes from yellow to deep red, and the consistency becomes viscous. The reaction is monitored by HPLC. For work-up, initially 300 ml of water are added, and subsequently approximately 300 ml of glacial acetic acid, until the pH is 5-6. During the addition, the temperature rises to −10° C., and a yellow suspension is formed. The reaction mixture is subsequently poured into 6 kg of ice-water, and the residue that has formed is filtered off with suction, washed with 5 l of water and dried in a drying cabinet at 30° C. overnight. This gives 339 g of a light-beige crude product which is freed from impurities by suspending it in approximately 3 l of toluene at 80-90° C. for 2 hours. After cooling, the product is filtered off with suction and dried. This gives 276 g of 2-nitro-6-methylbenzaldoxime.

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