Water → HCID 15870492, compound

Participants

Reaction Steps

To a mechanically stirred, cold (-74° C. dry ice-isopropanol bath) solution of (2-allyl-benzothiophen-3-yl)-(4-methoxy-phenyl)-methanone (11.27 g, 36.5 mmol) in anhydrous methylene chloride (112 mL) was added a 1 M solution of boron tribromide in methylene chloride (146 mL, 146 mmol, 4 eq) dropwise over a period of 1.25 hours under a dry nitrogen atmosphere. The reaction mixture was stirred in the warming bath overnight and at ambient temperature for 6 days. The reaction mixture was diluted with methylene chloride (total volume 500 mL) and added cautiously to water (1 L) with cooling in an ice bath. The layers were separated and the aqueous phase was extracted with ether (500 mL). The organic phases were combined, washed with a dilute aqueous solution of sodium bisulfite (2×1 L), and combined with silica gel. The solvents were removed and the adsorbate was flash chromatographed (82/18 petroleum ether/ethyl acetate) and chased with benzene and petroleum ether to provide the title compound as a white solid (5.79 g, 57%): mp 117-119° C.; NMR (CDCl3): δ 7.84 (dd, J=8, 1 Hz, 1H), 7.82 (dm, J=8 Hz, 1H), 7.45 (dd, J=8, 8, 1 Hz, 1H), 7.37-7.31 (multiplet with overlapping doublet at 7.33, J=8 Hz, 3H), 7.25 (s, 1H), 7.24 (dd, J=7, 1 Hz, 1H), 7.22 (dm, J=7 Hz, 1H), 7.10 (ddd, J=8, 7, 1 Hz, 1H), 7.01-6.98 (multiplet with overlapping doublet at 6.98, J=8 Hz, 2H); MS (EI): [M+] 276 (100%); Anal. Calc. for C18H12OS: C, 78.23, H, 4.38, N, 0.00. Found: C, 77.83, H, 4.22, N, 0.05.

Provenance & Evidence