Methanesulfonic Acid → 1352398-60-7

Participants

Reaction Conditions

Reaction Steps

A 1000 ml 3-neck round bottom flask, fitted with an overhead stirrer, was charged with 5,7-difluoro-2,3-dihydro-1H-indene-1-one (10 g, 59.4 mmol) followed by dry dichloromethane (100 ml) and methanesulfonic acid (71.3 ml, 1.1 mol). The reaction was cooled to 0° C. (ice bath) and to this was added sodium azide (5.41 g; 83.2 mmol) in 4 equal portions over 20 minutes. The reaction was stirred at 0° C. for 2 hours and then a 20% aqueous solution of sodium hydroxide (175 ml) was added over 30 minutes with vigorous stirring. After complete addition the mixture was transferred to a separatory funnel and the methylene chloride phase was isolated. This was shaken with an equal volume of 50% diluted brine solution. The organic phase was collected and the aqueous phases were back extracted with dichloromethane (2×80 ml). The organic phases were combined, dried (magnesium sulfate), filtered and concentrated in vacuo. The crude residue was purified via HPLC on silica gel, eluting with 40% to 95% ethyl acetate/hexanes to provide the desired product as a white solid (8.364 g). (M+H)+=184 m/e.

Provenance & Evidence