N#N.[C:3]([O:7][C:8](=[O:23])[NH:9][C:10]1[N:11]=[C:12]([CH2:15][CH2:16][CH2:17][CH2:18][C:19]([F:22])([F:21])[CH3:20])[O:13][CH:14]=1)([CH3:6])([CH3:5])[CH3:4].[H-].[Na+].[CH3:26][C:27]1[O:28][C:29]([C:35]2[CH:36]=[C:37]([CH3:41])[CH:38]=[CH:39][CH:40]=2)=[C:30]([C:32](Cl)=[O:33])[N:31]=1>C1COCC1.O>[C:3]([O:7][C:8](=[O:23])[N:9]([C:10]1[N:11]=[C:12]([CH2:15][CH2:16][CH2:17][CH2:18][C:19]([F:22])([F:21])[CH3:20])[O:13][CH:14]=1)[C:32]([C:30]1[N:31]=[C:27]([CH3:26])[O:28][C:29]=1[C:35]1[CH:36]=[C:37]([CH3:41])[CH:38]=[CH:39][CH:40]=1)=[O:33])([CH3:6])([CH3:4])[CH3:5]In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a solution of [2-(5,5-difluoro-hexyl)-oxazol-4-yl]-carbamic acid tert-butyl ester (74 mg, 0.24 mL) in THF (2.0 mL) was added to a suspension of NaH (26 mg, 0.60 mmol) in THF (0.5 mL) at 0° C. The resulting suspension was stirred at 0° C. for 5 min and at rt for 30 min. It was cooled to 0° C. and treated dropwise with a solution of the above prepared 2-methyl-5-m-tolyl-oxazole-4-carbonyl chloride in THF (1.5 mL). The resulting suspension was stirred for 30 min at 0° C. followed by 2 h at rt. Water was then added and the aq. layer was extracted several time with EA. The combined org. extracts were dried over Na2SO4, filtered, and the solvent was removed under reduced pressure. Purification of the residue by FC (7:3 hept-EA) gave the title compound as a colorless oil. TLC: rf (7:3 hept-EA)=0.18. LC-MS-conditions 02: tR=1.17 min, [M+H]+=504.17.
Loading…