Benzyl chloroformate → 2,6-Difluoro-3-nitro-benzoic acid benzyl ester

Participants

Reaction Steps

2,4-Difluoro-1-nitro-benzene (46, 1.4 mL, 13.0 mmol) and benzyl chloroformate (31, 10.42 g, 61.1 mmol) in 20 mL of tetrahydrofuran is cooled to −78° C. and stirred for 1 hour. Lithium diisopropylamine (1.5 g, 14.0 mmol) is added dropwise and the reaction is stirred at −78° C. for 1 hour, then warmed to room temperature over 2 hours. The reaction was purified by silica gel chromatography, eluting with hexane:ethyl acetate 90:10. Appropriate fractions are combined and concentrated under vacuum, then washed with methanol and the solid collected by filtration to provide the desired compound (47, 110 mg).

Provenance & Evidence