Sodium Nitrite → 5-hydroxy-6-methylisoquinolin-1(2H)-one

Participants

Reaction Conditions

Reaction Steps

5-Amino-6-methylisoquinolin-1(2H)-one (2.00 g, 11.48 mmol) was dissolved in sulfuric acid (24.3 mL, 287 mmol) (75%, 35 mL). The solution was cooled to 0° C. then a solution of sodium nitrite (12.1 mmol) in sulfuric acid (5 mL) was added dropwise over 15 min. The resulting solution was stirred at 0° C. for 45 min and then the reaction mixture was heated to 70° C. and stirred for 16 h. The reaction mixture was cooled in an ice bath for 15 min, then 100 g of ice was added. The mixture was filtered. The filter cake was washed with water for 4 times until the filtrate became neutral by pH paper. The filter cake was air dried to give 5-hydroxy-6-methylisoquinolin-1(2H)-one as a dark gray solid (1.39 g, 69% yield). MS (ESI, pos. ion) m/z: 176 [M+H]+

Provenance & Evidence