Methyl iodide → 7-Chloro-5-(2'-chloro-phenyl)-1,3-dihydro-3-(dimethylaminomethylene)-1-methyl-2H-1,4-benzodiazepin-2-one

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Reaction Steps

35.6 gm of a methanolic 30% sodium methylate solution were added dropwise to a solution of 46.5 gm of 7-chloro-5-(2'-chloro-phenyl)-1,3-dihydro-3-(dimethylamino-methylene)-2H-1,4-benzodiazepin-2-one in 300 ml of dry dimethylformamide at room temperature, accompanied by stirring, and the resulting mixture was stirred for 30 minutes more at room temperature and subsequently cooled to +5°C while stirring. Then, while maintaining that temperature by cooling, 58 gm of methyl iodide were added at a slow dropwise rate, again while stirring, and the resulting mixture was stirred for 90 minutes more at +5°C. Thereafter, the yellow precipitate which had formed was collected by vacuum filtration, washed with much water, dried and recrystallized from isopropanol, yielding the compound named in the heading above, which had a melting point of 199°-200°C.

Provenance & Evidence