反应详情

The ester 134-2 obtained in step 2 was stirred in DCM (15 ml) with trifluoroacetic acid (TFA, 3 ml) at room temperature overnight. After concentrated by evaporation, the residue was redistributed between ethyl acetate (30 ml) and 5% Na2CO3 aqueous solution (30 ml). The aqueous phase was acidified to pH around 2 with 6 N HCl solution and extracted with ethyl acetate (40 ml×2). The organic extraction was evaporated to give 2-(3-methyl-4-(pyridazin-4-yl)phenyl)acetic acid 134-3 as a solid which is used for reaction without further purification.

1. concentrationAfter concentrated by evaporation
2. extractionextracted with ethyl acetate (40 ml×2)
3. extractionThe organic extraction
4. customwas evaporated