[NH2:1][C:2]([NH2:4])=[O:3].[C:5]1([CH3:13])[CH:10]=[CH:9][C:8]([CH:11]=O)=[CH:7][CH:6]=1.[C:14]([O:20][CH2:21][CH3:22])(=[O:19])[CH2:15][C:16]([CH3:18])=O.C(O)(=O)C.B(F)(F)F.CCOCC>O1CCCC1.[Cu]Cl>[CH3:18][C:16]1[NH:4][C:2](=[O:3])[NH:1][CH:11]([C:8]2[CH:9]=[CH:10][C:5]([CH3:13])=[CH:6][CH:7]=2)[C:15]=1[C:14]([O:20][CH2:21][CH3:22])=[O:19]A suspension of urea (2,70 g; 45 mmol), copper (I) chloride (0,297 g; 3 mmol), p-tolualdehyde (3,53 ml; 30 mmol), ethyl acetoacetate (3,81 ml; 30 mmol), acetic acid (0,172 ml; 3 mmol) and boron trifluoride etherate (4,90 ml; 39 mmol) in dry tetrahydrofuran (60 mL) was heated to reflux for 21 h. After cooling to room temperature, the reaction mixture was quenched by adding a saturated solution of sodium hydrogen carbonate and the aqueous solution was extracted with ethyl acetate. The organic layer was concentrated under reduced pressure, the residue was suspended in toluene and left standing at room temperature for 24 h. The formed solid was filtered, washed with toluene and dried under reduced pressure to afford 7,45 g (91%) of the title compound as a green solid.
Wird geladen…
