N-bromobutanimide → (+/-)-6-Bromo-2a-methyl-1,2,2a,5-tetrahydropyrrolo[4,3,2-de]quinolin-4(3H)-one
Reaction equation
[CH3:1][C:2]12[CH2:13][NH:12][C:10]3[C:11]1=[C:6]([CH:7]=[CH:8][CH:9]=3)[NH:5][C:4](=[O:14])[CH2:3]2.[Br:15]N1C(=O)CCC1=O>C(Cl)Cl>[Br:15][C:7]1[C:6]2[NH:5][C:4](=[O:14])[CH2:3][C:2]3([CH3:1])[CH2:13][NH:12][C:10]([C:11]=23)=[CH:9][CH:8]=1Participants
4
Procedure
To a solution of (±)-2a-methyl-1,2,2a,5-tetrahydropyrrolo[4,3,2-de]quinolin-4(3H)-one from Step A (525 mg, 2.79 mmol) in CH2Cl2 (15 mL) at 0° C. was added N-bromosuccinimide (496 mg, 2.79 mmol) and the mixture was allowed to warm slowly to ambient temperature. After 5 h, the reaction mixture was quenched with saturated aqueous NaHCO3 (10 mL) and extracted with EtOAc (150 mL). The organic layer was washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography, eluting with a gradient of CH2Cl2:CH3CN —100:0 to 75:25, to give the title compound. MS: m/z=267 (M+1).