3-Fluoro-4-nitrobenzaldehyde → (E)-3-(3-Fluoro-4-nitro-phenyl)-acrylic acid tert-butyl ester

Participants

Reaction Steps

Potassium tert-butylate (0.438 g, 3.9 mmol) was added to a suspension of tert-butoxy carbonyl methyl triphenyl phosphonium bromide (1.61 g, 3.9 mmol; CAS Reg. No. 35000-37-4) in tetrahydrofuran (10 ml). The suspension was stirred for 15 min at ambient temperature. 3-Fluoro-4-nitrobenzaldehyde (600 mg, 3.5 mmol; CAS Reg. No. 160538-51-2) was added, the mixture was stirred for 1.5 h at ambient temperature, poured onto water and extracted three times with ethyl acetate. The combined organic layers were washed with brine and dried over magnesium sulfate. The solid was filtered off and the filtrate was concentrated under reduced pressure to give a brown oil which was purified by column chromatography on silica gel using an MPLC system (CombiFlash Companion, Isco Inc.) eluting with a gradient of heptane:methyl tert-butyl ether (100:0 to 80:20 v/v) to afford the title compound as a brown oil (812 mg, 3.04 mmol; 86%).

Provenance & Evidence