1-(4-Bromo-2-thienyl)ethan-1-one → 2-Bromo-1-(4-bromo-2-thienyl)ethanone

To 1-(4-bromothiophen-2-yl)ethanone (10 g, 48.8 mmol) in methanol (98 mL) and dichloromethane (163 mL) is added tetra-n-butylammonium tribromide (28.8 g, 58.5 mmol). The reaction mixture is concentrated under reduced pressure at 50° C. to give a residue which is purified by silica gel chromatography, eluting with dichloromethane to give crude 2-bromo-1-(4-bromo-2-thienyl)ethanone. To a solution of the crude 2-bromo-1-(4-bromo-2-thienyl)ethanone in acetonitrile (200 ml) is added potassium carbonate (20.2 g, 146 mmol) and diallylamine (9.48 g, 97.5 mmol). The reaction is stirred at room temperature for 2 hours. Water is added and the solution is extracted with ethyl acetate. The organic phases are combined, dried over sodium sulfate, filtered, and concentrated under reduced pressure to give the crude title compound. ES/MS (m/e): (79Br/81Br) 300/302 (M+H).

1. concentrationThe reaction mixture is concentrated under reduced pressure at 50° C.
2. customto give a residue which
3. customis purified by silica gel chromatography
4. washeluting with dichloromethane

ORD record

ord-480a16c86cde4487aa6330925aa96a1d

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08889856B2