反应详情

2,4,5-Trifluorobenzoic acid (3.00 g, 17.0 mmol), N-ethyl-N-isopropylpropan-2-amine (8.9 mL, 6.6 g, 51.1 mmol), 2,4,6-tripropyl-1,3,5,2,4,6-trioxatriphosphorinane-2,4,6-trioxide 50% solution in EtOAc/DMF (12.7 mL, 13.6 g, 42.6 mmol) and methanesulfonamide (3.24 g, 34.1 mmol) were suspended in THF (40 mL) and stirred under a nitrogen atmosphere at reflux for 18 hours. The reaction mixture was cooled, concentrated in vacuo and the residue suspended in water (pH=4). The mixture was acidified to pH=2 with an aqueous solution of potassium hydrogen sulfate (0.5 M). The mixture was extracted with EtOAc (1×100 mL). The organic layer was washed with brine (2×50 mL), dried over sodium sulfate, filtered and evaporated to yield the crude solid. The crude solid was triturated with hexane to yield the title compound as an off-white crystalline solid (3.08 g, 72%).

1. temperatureat reflux for 18 hours
2. temperatureThe reaction mixture was cooled
3. concentrationconcentrated in vacuo
4. extractionThe mixture was extracted with EtOAc (1×100 mL)
5. washThe organic layer was washed with brine (2×50 mL)
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. customevaporated
9. customto yield the crude solid
10. customThe crude solid was triturated with hexane