[S:1]([N:11]1[C:19]2[C:14](=[C:15]([CH:20](O)[CH3:21])[CH:16]=[CH:17][CH:18]=2)[CH:13]=[CH:12]1)([C:4]1[CH:10]=[CH:9][C:7]([CH3:8])=[CH:6][CH:5]=1)(=[O:3])=[O:2].P(Br)(Br)[Br:24].C([O-])(O)=O.[Na+]>C(Cl)Cl.CCOCC>[Br:24][CH:20]([C:15]1[CH:16]=[CH:17][CH:18]=[C:19]2[C:14]=1[CH:13]=[CH:12][N:11]2[S:1]([C:4]1[CH:10]=[CH:9][C:7]([CH3:8])=[CH:6][CH:5]=1)(=[O:3])=[O:2])[CH3:21]To a solution of 282 (400 mg, 1.27 mmol) in dry DCM (2 mL) and dry Et2O (2 mL) at 0° C. under Argon was added PBr3 (515 mg, 1.91 mmol) and the mixture was stirred at RT overnight. The mixture was poured into cold NaHCO3 (aq.) and extracted with EtOAc. The combined extracts were washed sequentially with water and brine, dried (Na2SO4), filtered and concentrated in vacuo to afford 450 mg (92%) of 4-(1-bromoethyl)-1-tosyl-1H-indole (284) give as a yellow oil, which was used in the next step without further purification: 1H NMR (400 MHz, CDCl3) δ 7.94 (d, J=8.0 Hz, 1H), 7.78 (d, J=8.0 Hz, 2H), 7.65 (d, J=2.8 Hz, 1H), 7.35-7.23 (m, 4H), 6.89 (d, J=2.8 Hz, 1H), 5.53-5.50 (m, 1H), 2.36 (s, 3H), 2.13 (d, J=6.8 Hz, 3H).
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