反应详情

A solution of 3-(4,5-dimethylpyridin-2-yl)-2,2-dimethyl-2H-benzo[e][1,3]oxazin-4(3H)-one (9 g, 0.03 mol) in concentrated hydrochloric acid (100 mL) was heated at reflux overnight. The mixture was basified by saturated solution of Na2CO3 and extracted with CH2Cl2 (100 mL×3). The combined organic layers were dried over anhydrous Na2SO4, filtered and evaporated under vacuum to give 4,5-dimethylpyridin-2-amine (3.8 g, 97%), that was directly used in the next step without further purification.

1. temperatureat reflux overnight
2. extractionextracted with CH2Cl2 (100 mL×3)
3. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
4. filtrationfiltered
5. customevaporated under vacuum