Ethyl 2-(triphenylphosphoranylidene)propionate → (E)-ethyl 2-methyl-3-(3,4,5-trifluorophenyl)acrylate
反応式
[F:1][C:2]1[CH:3]=[C:4]([CH:7]=[C:8]([F:11])[C:9]=1[F:10])[CH:5]=O.C1(P(C2C=CC=CC=2)(C2C=CC=CC=2)=[C:19]([CH3:25])[C:20]([O:22][CH2:23][CH3:24])=[O:21])C=CC=CC=1>CN(C=O)C>[CH3:25]/[C:19](=[CH:5]\[C:4]1[CH:3]=[C:2]([F:1])[C:9]([F:10])=[C:8]([F:11])[CH:7]=1)/[C:20]([O:22][CH2:23][CH3:24])=[O:21]参加物
4
実験手順
To a solution of dry DMF (50 mL) under N2 was added 3,4,5-trifluorobenzaldehyde (4.26 g, 26.6 mmol) followed by ethyl 2-(triphenylphosphoranylidene)propionate (10.6 g, 29.3 mmol) in portions, keeping the solution at room temperature. After 1 hour, TLC (10% EtOAC in Hexanes) showed complete conversion, and the solvent was removed by rotary evaporation. The resulting material was brought up in 50 mL methyl t-butyl ether (MBTE) and the precipitate removed by filtration and washed with additional MBTE (3×50 mL). After concentration, the resulting filtrate was applied onto a silica gel column (25% EtOAc in hexanes) resulting in 6.0 g of the title compound (93%) as a white powder.