Chlorotrimethylsilane → 5-(Trimethylsilyl)furan-3-carbaldehyde
Reaktionsgleichung
Br[C:2]1[O:6][CH:5]=[C:4]([CH:7]=[O:8])[CH:3]=1.C([Li])(C)(C)C.[CH3:14][Si:15](Cl)([CH3:17])[CH3:16]>>[CH3:14][Si:15]([CH3:17])([CH3:16])[C:2]1[O:6][CH:5]=[C:4]([CH:7]=[O:8])[CH:3]=1Komponenten
4
Versuchsvorschrift
According to the above procedure, 3-furaldehyde is brominated to give 5-bromo-3-furaldehyde which is then reacted with a Grignard reagent (R3MgX) and the resulting mixture treated with t-butyl lithium and trimethylsilyl chloride to give 4-[R3 --CH(OH)]-2-trimethylsilylfuran. Alternatively, 5-bromo-3-furaldehyde is converted to the dimethylacetal, then treated with t-butyl lithium and trimethylsilyl chloride to give 5-trimethylsilyl-3-furaldehyde which is reacted with R3MgX or R3Li to give 4-[R3 --CH(OH)]-2-trimethylsilylfuran. Treating this intermediate with oxygen and irradiation using an initiator such as Rose Bengal gives 4-[R3 --CH(OH]-5-hydroxy-2(5H)-furanone.