反应详情

A solution of 1-tert-butoxycarbonyl-4-(5-fluoro-3-(2,2,2-tri-fluoroethyl)-2-oxo-1-benzimidazolinyl)piperidine (4.17 g, 10 mmol.) in chloroform (50 mL) containing trifluoroacetic acid (5.5 mL) was stirred at room temp. under an inert atmosphere for 6-12 hours until reaction was complete. The solvent and excess TFA were removed and the residue redissolved in chloroform. This solution was washed with Na2CO3 /NaOH solution. The organic layer was dried (Na2SO4), filtered through a pad of charcoal, and the solvent evaporated to give 4-(5-fluoro-3-(2,2,2-trifluoroethyl)-2-oxo-1-benzimidazolinyl)piperidine as a viscous oil which was used as is. A sample of this material was converted to the HCl salt and after crystallization from methanol gave a white solid, mp: >280° C.

1. customThe solvent and excess TFA were removed
2. dissolutionthe residue redissolved in chloroform
3. washThis solution was washed with Na2CO3 /NaOH solution
4. dry with materialThe organic layer was dried (Na2SO4)
5. filtrationfiltered through a pad of charcoal
6. customthe solvent evaporated