Chlorosulfonic acid → 1-(chloromethyl)-3-(trifluoroacetyl)-1,2-dihydro-3H-benzo[e]indole-7-sulfonyl chloride
Reaction equation
[Cl:1][CH2:2][CH:3]1[C:11]2[C:10]3[CH:12]=[CH:13][CH:14]=[CH:15][C:9]=3[CH:8]=[CH:7][C:6]=2[N:5]([C:16](=[O:21])[C:17]([F:20])([F:19])[F:18])[CH2:4]1.[Cl:22][S:23](O)(=[O:25])=[O:24]>>[Cl:1][CH2:2][CH:3]1[C:11]2[C:10]3[CH:12]=[CH:13][C:14]([S:23]([Cl:22])(=[O:25])=[O:24])=[CH:15][C:9]=3[CH:8]=[CH:7][C:6]=2[N:5]([C:16](=[O:21])[C:17]([F:20])([F:18])[F:19])[CH2:4]1Participants
3
Conditions
- Temperature
- 60 °C
Procedure
Solid 108 (1.6 g, 5.1 mmol) was gradually added to chlorosulfonic acid (6.0 mL, 90 mmol) with ice bath cooling. The mixture was then heated to 60° C. for 2 h, and the reaction was quenched by pouring slowly, with stirring, into ice-water. The precipitated solid was collected, washed with water, dried and chromatographed on silica gel. Elution with EtOAc/petroleum ether (from 1:4 to 1:1) gave 1-(chloromethyl)-3-(trifluoroacetyl)-1,2-dihydro-3H-benzo[e]indole-7-sulfonyl chloride (113) (0.53 g, 25%) as a pale yellow solid: mp (EtOAc/petroleum ether) 189-192° C.; 1H NMR (CDCl3) δ 8.70-8.64 (m, 2H), 8.13-8.08 (m, 2H), 8.00 (d, J=9.0 Hz, 1H), 4.72-4.68 (m, 1H), 4.55-4.48 (m, 1H), 4.33-4.25 (m, 1H), 3.98-3.93 (m, 1H), 3.68-3.61 (m, 1H), 13C NMR δ 154.9 (q, JC-F 38.4 Hz), 143.9, 140.7, 132.7, 131.8, 130.1, 130.0, 125.8, 124.8, 123.2, 119.6, 115.9 (q, JC-F 288 Hz), 52.8, 45.4, 42.4. Anal. (C15H10Cl2F3NO3S) C, H, N, Cl.