Methanesulfonic Acid → 6-Fluoro-1,2,3,4-tetrahydroisoquinolin-1-one

Participants

Reaction Steps

To a solution of 5-fluoro-1-indanone (1.5 g, 10 mmol) and methanesulfonic acid (6 ml, 90 mmol) in anhydrous dichloromethane (6 ml) was added sodium azide (1.30 g, 20 mmol) whilst maintaining the temperature of the reaction between 21 and 26° C. The reaction was stirred for 15 hrs and then cooled in ice and basified using 5N sodium hydroxide solution. The organic phase was separated and the aqueous phase extracted with dichloromethane (2×10 ml). The combined organics were washed with water and brine, then dried (MgSO4) and evaporated in vacuo. The resulting residue was purified by flash column chromatography (50% ethyl acetate in dichloromethane) to afford the title compound as a light brown solid (1.0 g, 61%). HPLC retention time 3.18 min. Mass spectrum (ES+) m/z 166 (M+H).

Provenance & Evidence