Carbon tetrabromide → 2-(Bromomethyl)-1-benzofuran

반응식

[O:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[CH:3]=[C:2]1[CH2:10]O.C(Br)(Br)(Br)[Br:13].C1(P(C2C=CC=CC=2)CCCP(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>ClCCl>[Br:13][CH2:10][C:2]1[O:1][C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[CH:3]=1

참가 물질

실험 절차

To benzofuran-2-yl-methanol (4.3 g, 29.0 mmol, 1 eq., Example 140, Step 1), dichloromethane (200 mL) was added and the solution was cooled using an ice-ethanol bath. Then carbon tetrabromide (10.6 g, 31.9 mmol, 1.1 eq.) and 1,3-bis(diphenylphosphino)-propane (6.6 g, 16.0 mmol, 0.55 eq.) were added under argon, and the reaction was allowed to slowly warm to room temperature for 2.5 hours. After work-up and flash column chromatography, 2-bromomethyl-benzofuran was obtained in quantitative yield. 1H NMR (400 MHz, DMSO-d6) δ ppm 4.9 (s, 2 H) 7.0 (dd, J=5.3, 0.5 Hz, 1 H) 7.3 (dd, 1 H) 7.4 (m, 1 H) 7.6 (m, 2 H).