反应详情

A solution of 183 mg (1.49 mmol) of 2,3-dimethylpyridine 1-oxide in 0.6 ml of conc. sulphuric acid is treated while coollng with ice with 0.2 ml of 65% nitric acid (d=1.4). The reaction mixture is stirred at 9° for 24 hours and poured on to a mixture of ice and sodium carbonate, whereupon the resulting mixture is extracted with methylene chloride and the methylene chloride phase is dried and evaporated. The residue crystallized from ethanol/n-pentane, gives 2,3-dimethyl-4-nitropyridine 1-oxide of melting point 99°-102°.

1. extractionis extracted with methylene chloride
2. dry with materialthe methylene chloride phase is dried
3. customevaporated
4. customThe residue crystallized from ethanol/n-pentane