Chlorine → 4-(5-Chloro-2,3-dihydrobenzofuran-7-yl)-1,1,1-trifluoro-4-methylpentan-2-one

Participants

Reaction Steps

A solution of 4-(2,3-dihydrobenzofuran-7-yl)-1,1,1-trifluoro-4-methylpentan-2-one (20.8 g, 76.2 mmol) in 200 mL of acetic acid was treated with a solution of chlorine gas in acetic acid (˜1.19 M). The reaction was monitored by 1H-NMR. The mixture was quenched with 500 mL of water and solid sodium bicarbonate (˜500 g) was added carefully during 1 hour. The mixture was poured onto 500 mL of ethyl acetate. The phases were separated and the aqueous layer was extracted with three 500 mL portions of ethyl acetate. The combined organic layers were washed with two 100 mL portions of brine, dried over magnesium sulfate, filtered, and concentrated in vacuo to afford 23.4 g of 4-(5-chloro-2,3-dihydrobenzofuran-7-yl)-1,1,1-trifluoro-4-methylpentan-2-one (100%), which was used without purification.

Provenance & Evidence