N-bromobutanimide → 5-Bromo-2-ethyl-2,3-dihydro-benzofuran

Participants

Reaction Steps

N-Bromosuccinimide (8.66 g, 48.6 mmol) was added to a solution of 2-ethyl-2,3-dihydrobenzofuran (preparation 98) in dichloromethane (70 mL) and the mixture was stirred at room temperature for 18 hours. The mixture was then diluted with dichloromethane (200 mL) and washed with water (200 mL) and sodium meta-bisulphite (200 mL). The organic solution was dried over magnesium sulfate and concentrated in vacuo to give a yellow oil that was purified by HPLC using a Chiralcel OJ 250*20 mm column and hexane:isopropanol (95:5) as the eluant to afford the first enantiomer of the title compound. Further elution provided the second isomer of the title compound, 2.95 g. 1H NMR (400 MHz, CDCl3) δ: 7.24 (1H, m), 7.18 (1H, m), 6.62 (1H, d), 4.75 (1H, m), 3.30-3.20 (1H, m), 2.92-2.80 (1H, m), 1.77-1.88 (1H, m), 1.75-1.65 (1H, m) 1.00 (3H, m) ppm.

Provenance & Evidence