Hydrochloric Acid → 5-Formyl-3-methyl-thiophene-2-carboxylic acid (2,2,2-trifluoro-ethyl)-amide
Reaction equation
Cl.[F:2][C:3]([F:20])([F:19])[CH2:4][NH:5][C:6]([C:8]1[S:9][C:10]([CH:14]2OCC[O:15]2)=[CH:11][C:12]=1[CH3:13])=[O:7]>CC(C)=O>[F:20][C:3]([F:2])([F:19])[CH2:4][NH:5][C:6]([C:8]1[S:9][C:10]([CH:14]=[O:15])=[CH:11][C:12]=1[CH3:13])=[O:7]Participants
4
Procedure
HCl (2N, 4 ml) is added to a solution of 5-[1,3]dioxolan-2-yl-3-methyl-thiophene-2-carboxylic acid (2,2,2-trifluoro-ethyl)-amide (450 mg) in acetone (10 ml). After 4 hours at 50° C. and one night at room temperature, the reaction is quenched with water. The reaction mixture is extracted three times with ethyl acetate. The combined organic phases are dried over Na2SO4 and concentrated in vacuo. The crude product is purified on a semi-preparative HPLC to yield 5-formyl-3-methyl-thiophene-2-carboxylic acid (2,2,2-trifluoro-ethyl)-amide (196 mg) as a yellowish oil. MS (HPLC/MS): 252 (MH+). Retention time: 2.54 min.