Hydrochloric Acid → (E)-(5,6-dihydro-1,4,2-dioxazin-3-yl)(2-hydroxyphenyl)methanone O-methyloxime

Participants

Reaction Steps

1.2 g (0.0054 mol) of Z-(5,6-dihydro-1,4,2-dioxazin-3-yl)-(2-hydroxy-phenyl)-methanone oxime (V-1) in 5 ml of dimethylformamide are stirred at 20° C. together with 0.66 g (0.0062 mol) of sodium carbonate initially for 30 minutes. 0.83 g (0.00658 mol) of dimethyl sulphate is then added and stirring is continued at 20° C. for a further 16 hours. The reaction mixture is adjusted to a slightly acidic pH using 2 N aqueous hydrochloric acid and extracted with ethyl acetate. The organic phase is dried over sodium sulphate and the solvent is distilled off under reduced pressure. 0.8 g (50.35% of theory) of Z-(5,6-dihydro-1,4,2-dioxazin-3-yl)-(2-hydroxy-phenyl)-methanone O-methyl-oxime (1) of a purity of 80.3% (HPLC) is obtained.

Provenance & Evidence