P(Cl)(Cl)(Cl)=O.CN([CH:14]=[O:15])C1C=CC=CC=1.[C:16]([C:20]1[S:21][CH:22]=[CH:23][CH:24]=1)([CH3:19])([CH3:18])[CH3:17].C(=O)(O)[O-].[Na+]>>[C:16]([C:20]1[S:21][C:22]([CH:14]=[O:15])=[CH:23][CH:24]=1)([CH3:19])([CH3:18])[CH3:17]Phosphorus oxychloride (24.04 g, 0.157 mol) was added dropwise to N-methylformanilide (21.24 g, 0.157 mol) and a yellow solid was produced. This was cooled to 0° C. for 1/2 hour, then 2-t-butylthiophene (20 g, 0.143 mol) was added dropwise and the mixture stirred at room temperature for 3 hours. The mixture was poured into ice/water, neutralised with sodium bicarbonate and extracted into diethyl ether. The ethereal extracts were washed with water, dried over anhydrous sodium sulphate and the solvent removed to give a brown liquid. Purification by column chromatography (silica eluted with petroleum ether/ethyl acetate 9:1) gave 5-t-butyl-2-thiophenecarboxaldehyde (21.01 g, 87%) as a yellow liquid.
Wird geladen…
