Dimethylformamide → 2-Methyl-6-nitrobenzaldoxime

Participants

Reaction Conditions

Reaction Steps

1200 ml of anhydrous DMF are initially charged in a 4 l reaction flask and cooled to −40° C. At this temperature, 336.5 g (4.56 mol) of potassium methoxide (95%) are added and suspended with stirring. A mixture of 300 g (1.92 mol) of 3-nitro-o-xylene (97%) and 274 g (2.52 mol) of n-butyl nitrite (95%) is then added dropwise at −40° C. over a period of 7 hours (if the mixture is cooled accordingly, the duration of this addition can be reduced as desired; a longer period of addition has not yet been tested; temperature variations between −35 and −45° C. are tolerated). The complete conversion of the starting material is checked by HPLC. The reaction discharge is then added with stirring, at from −5 to 0° C., to a mixture of 300 ml of water and 300 ml of glacial acetic acid. The reaction mixture is then poured onto 6 kg of ice-water and the solid is separated off by filtration (without any problems, filter resistance has not yet been determined) and washed twice with in each case 500 ml of water (careful: the crude product smells strongly). The crude product (HPLC: 96 area %) is purified by suspending the moist solid in 800 ml of toluene for 1.5 h. The solid is filtered off (without any problems, the filter resistance has not yet been determined) and dried at 50° C. in a vacuum drying cabinet.

Provenance & Evidence