反应详情

Trifluoroacetic acid (5 mL) was added to a solution of tert-butyl 2,2-difluoro-4-(5-methylthiophene-2-carbonyl)-1-oxa-4,9-diazaspiro[5.5]undecane-9-carboxylate (example 37, step d) (0.4 g) in dichloromethane (20 mL) at 20° C. The solution was allowed to stand at 20° C. for 25 minutes. Toluene (40 mL) was added and the solvents were removed under reduced pressure. The residue was evaporated down twice with acetonitrile. The resultant gum was triturated with ether to afford the subtitled compound. Yield 0.39 g.

1. customthe solvents were removed under reduced pressure
2. customThe residue was evaporated down twice with acetonitrile
3. customThe resultant gum was triturated with ether