[NH2:1][C:2]1[CH:14]=[C:13]2[C:5]([C:6]3[C:11]([CH2:15][CH2:16][CH2:17][CH3:18])([CH2:12]2)[CH2:10][CH2:9][C:8](=[O:19])[CH:7]=3)=[CH:4][C:3]=1[F:20].BrC1C(=O)C(Br)=C(Br)C(C)([N+:29]([O-:31])=[O:30])C=1Br>FC(F)(F)C(O)=O.CCOC(C)=O>[NH2:1][C:2]1[CH:14]=[C:13]2[C:5]([C:6]3[C:11]([CH2:15][CH2:16][CH2:17][CH3:18])([CH2:12]2)[CH2:10][CH2:9][C:8](=[O:19])[C:7]=3[N+:29]([O-:31])=[O:30])=[CH:4][C:3]=1[F:20]A solution of 7-amino-9a-butyl-6-fluoro-1,2,9,9a-tetrahydro-3H-fluoren-3-one (34.6 mg, 0.126 mmol) in trifluoroacetic acid (0.25 mL) was treated with 2,3,5,6-tetrabromo-4-methyl-4-nitro-2,5-cyclohexadien-1-one (59 mg, 0.126 mmol). The resulting mixture was placed under a N2 atmosphere, sonicated briefly, and stirred at room temperature for one hour. The mixture was diluted with EtOAc (15 mL), washed successively with water, 5% NaHCO3 and brine, dried over MgSO4, filtered, and evaporated under vacuum to a brown oil (86 mg). The crude product was purified by preparative layer chromatography on a 0.1×20×20 cm silica gel GF plate, developing with 2:1 hexanes-EtOAc. The major UV visible band was eluted with 5% MeOH in CH2Cl2, the eluant was concentrated under vacuum to an orange oil (16 mg, 40%), and the oil was lyophilized from benzene to afford 7-amino-9a-butyl-6-fluoro-4-nitro-1,2,9,9a-tetrahydro-3H-fluoren-3-one as an amorphous solid.
Wird geladen…