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

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%).

1. addition160538-51-2) was added
2. stirringthe mixture was stirred for 1.5 h at ambient temperature
3. additionpoured onto water
4. extractionextracted three times with ethyl acetate
5. washThe combined organic layers were washed with brine
6. dry with materialdried over magnesium sulfate
7. filtrationThe solid was filtered off
8. concentrationthe filtrate was concentrated under reduced pressure
9. customto give a brown oil which
10. customwas purified by column chromatography on silica gel using an MPLC system (CombiFlash Companion, Isco Inc.)
11. washeluting with a gradient of heptane:methyl tert-butyl ether (100:0 to 80:20 v/v)

ORD record

ord-68bd1c32871d4fd0a369144c0ca504bd

Source dataset

uspto-grants-2011_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08008505B2