反应详情

300 ml of concentrated sulphuric acid are added slowly while cooling with dry ice to 230 ml of concentrated nitric acid (68%; d=1.41), whereby the temperature of the mixture does not exceed 5°. A solution of 38.7 g (0.25 mol) of 2-chloromethyl-3-methylpyridine 1-oxide is added thereto and the mixture is stirred at 80° for 2 hours. The reaction mixture is poured on to a mixture of ice and methylene chloride, the aqueous phase is washed several times with methylene chloride and the methylene chloride solution is extracted with 10% sodium bicarbonate solution. The organic phase is dried with sodium sulphate and concentrated. The residue is recrystallized from ethyl acetate, there being obtained 2-chloromethyl-3-methyl-4-nitropyridine 1-oxide. The product exhibits a melting point of 126°-129°.

1. customdoes not exceed 5°
2. washthe aqueous phase is washed several times with methylene chloride
3. extractionthe methylene chloride solution is extracted with 10% sodium bicarbonate solution
4. dry with materialThe organic phase is dried with sodium sulphate
5. concentrationconcentrated
6. customThe residue is recrystallized from ethyl acetate, there