Acetic acid, 2-(triphenylphosphoranylidene)-, methyl ester → 3-(6-Bromopyridin-3-yl)acrylic acid methyl ester
Reaction equation
[CH3:1][O:2][C:3](=[O:24])[CH:4]=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[Br:25][C:26]1[N:31]=[CH:30][C:29]([CH:32]=O)=[CH:28][CH:27]=1>C1COCC1>[CH3:1][O:2][C:3](=[O:24])[CH:4]=[CH:32][C:29]1[CH:30]=[N:31][C:26]([Br:25])=[CH:27][CH:28]=1Participants
4
Procedure
20 g (59.8 mmol) of 2-(triphenylphosphoranylidene)acetic acid methyl ester were added, by portion, to a solution of 11.1 g (59.8 mmol) of 6-bromopyridine-3-carbaldehyde in anhydrous THF at 0° C. The mixture was stirred at 0° C. to room temperature for 4 h. The solvent was removed in vacuo and the residue was purified by chromatography (silica gel, cyclohexane/ethyl acetate 95:5) to give 13.1 g (90.4%) of the title compound (trans/cis ratio 95:5) as a white solid.