Sodium Hydroxide → Isoquinoline, 5-chloro-6-fluoro-

Participants

Reaction Conditions

Reaction Steps

7.0 g (38.1 mmol) of 6-fluoroisoquinoline (3) were dissolved in 60 mL of concentrated sulfuric acid. At 0° C. 10.18 g of N-chloro succinimide were added. After 1 h another 5.2 g of N-chloro succiminide were added and the solution was heated to 50° C. Two more portions of 5.2 g N-chloro succinimide were added successively and stirring was continued at 50° C. until the reaction was complete. The reaction mixture was cooled to room temperature, was poured on ice and adjusted to pH 10 by addition of sodium hydroxide. The precipitate was filtered off, dissolved in dichloromethane and washed with aqueous sodium hydroxide. The organic layer was dried over magnesium sulfate, evaporated and the crude product was purified by preparative HPLC to yield 4.04 g of 5-chloro-6-fluoro-isoquinoline (7) as trifluoroacetate. Rt=0.97 min (Method A). Detected mass: 182.0/184.0 (M+H+).

Provenance & Evidence