Abstract
Reactions of diketene with amino-heterocycles, such as aminoquinoline, thiazole and pyrimidine derivatives, were examined.
2-Aminoquinoline (VI) was converted to 2-acetoacetamidoquinoline (VII) in 82% yield, and 4-amino-isomer (VIII) was transformed to 1-(4-quinolyl)-3-acetyl-6-methyl-2, 4(1H, 3H)-pyridinedione (IX) in 60% yield. 2-Aminothiazole (X) reacted with diketene to give 2-acetoacetamidothiazole (XI) (70%) and 7-methyl-5H-thiazole [3, 2-a] pyrimidine-5-one (XII) (26%).
2-Aminopyrimidine (XIII), 2-amino-4-methoxy-6-methylpyrimidine (XVII), 2-amino-4-methylpyrimidine (XIX), 4-amino-6-chloropyrimidine (XXIII) and 4-amino-6-alkoxy-pyrimidine (CH3O (XXIV), C2H5O (XXV), (CH3)2⋅CHO (XXXI)) were converted to their acetoacetyl derivatives comparatively in good yields.
