[F:1][C:2]1[CH:3]=[C:4]2[C:8](=[CH:9][CH:10]=1)[NH:7][CH:6]=[C:5]2[CH2:11][CH2:12]O.C(Cl)Cl.[Br:17]C(Br)(Br)Br.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>O>[Br:17][CH2:12][CH2:11][C:5]1[C:4]2[C:8](=[CH:9][CH:10]=[C:2]([F:1])[CH:3]=2)[NH:7][CH:6]=12-(5-Fluoro-1H-indol-3-yl)-ethanol (20.0 g, 112 mmol) was dissolved in abs. CH2Cl2 (250 ml), and tetrabromomethane (56.0 g, 170 mmol) was added at RT. Triphenylphosphine (44.0 g, 165 mmol) was then added in portions at RT, while cooling with water. The solution was stirred at RT for 2.5 h and then concentrated i. vac. The residue was absorbed on to silica gel and divided into two equal portions. The crude product was purified by flash chromatography over 2 columns each with 500 g of silica gel and cyclohexane/ethyl acetate (9:1→4:1). Yield: 25.4 g (93%), red solid
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