Methylenetriphenylphosphorane → [4-(5-Tert-butyl-4-isopropoxy-2-methyl-3-vinyl-phenylethynyl)-phenyl]acetic acid methyl ester
Reaktionsgleichung
[CH2:1]=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.[CH3:21][O:22][C:23](=[O:50])[CH2:24][C:25]1[CH:30]=[CH:29][C:28]([C:31]#[C:32][C:33]2[CH:38]=[C:37]([C:39]([CH3:42])([CH3:41])[CH3:40])[C:36]([O:43][CH:44]([CH3:46])[CH3:45])=[C:35]([CH:47]=O)[C:34]=2[CH3:49])=[CH:27][CH:26]=1>O1CCCC1>[CH3:21][O:22][C:23](=[O:50])[CH2:24][C:25]1[CH:30]=[CH:29][C:28]([C:31]#[C:32][C:33]2[CH:38]=[C:37]([C:39]([CH3:42])([CH3:41])[CH3:40])[C:36]([O:43][CH:44]([CH3:45])[CH3:46])=[C:35]([CH:47]=[CH2:1])[C:34]=2[CH3:49])=[CH:27][CH:26]=1Komponenten
4
Versuchsvorschrift
A solution of methylidene triphenyl phosphorane [5 mL of 0.1M solution, 0.5 mmol, generated from methyl triphenylphosphonium bromide (2.5 g, 7 mmol) and 1.6M n-butyllithium solution in hexanes (2.9 mL, 4.7 mmol) in 50 mL of tetrahydrofuran] was added to a solution of [4-(5-tert-butyl-3-formyl-4-isopropoxy-2-methyl-phenylethynyl)-phenyl]-acetic acid methyl ester (Intermediate 144, 0.052 g, 0.13 mmol) in tetrahydrofuran (1 mL). After 1 h the reaction mixture was quenched with water and extracted with ethyl acetate. The organic phase was washed with water and brine, dried over anhydrous sodium sulfate, filtered and evaporated in vacuo to a clear oil that after flash column chromatography over silica gel (230–400 mesh) using 5% ethyl acetate in hexane as the eluent afforded the title compound (0.02 g, 39%).