Triethylamine → 4-Bromo-N-methoxy-N-methylbenzamide

To a stirred solution of 4-bromobenzoyl chloride (20.0 g, 91.1 mmol) in dichloromethane (300 mL) at −78° C. was added triethylamine (28.0 mL, 200.0 mmol), and O,N-dimethylhydroxylamine hydrochloride (9.33 g, 95.6 mmol). The resulting solution was allowed to warm to room temperature, stirred for 1.5 hours, and then concentrated. The residue was triturated in acetone and the resulting solid was dissolved in ethyl acetate washed with water and brine. The organic layer was dried over magnesium sulfate, filtered, and concentrated to give 4-bromo-N-methoxy-N-methylbenzamide (18.6 g, 84%). To a solution of 4-bromo-N-methoxy-N-methylbenzamide (3.0 g, 12.29 mmol) in THF (30 mL) at 0° C. under nitrogen was added 2-thienyllithium (1.0 M in THF, 15 mL, 15 mmol) slowly over 10 minutes. The solution was stirred at 0° C. for 1 hour, poured into a saturated aqueous ammonium chloride solution (150 mL), and extracted several times with ethyl acetate. The combined organic layers were dried over magnesium sulfate, filtered, and concentrated. The residue was triturated with ether to give (4-bromophenyl)(thien-2-yl)methanone as a brown solid (1.1 g, 34%). MS (ES) m/z 266.9.

1. concentrationconcentrated
2. customThe residue was triturated in acetone
3. dissolutionthe resulting solid was dissolved in ethyl acetate
4. washwashed with water and brine
5. dry with materialThe organic layer was dried over magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated

ORD record

ord-c9b9aba98efb4797b9e4b00f7c5c188f

Source dataset

uspto-grants-2008_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07319152B2