Synthesis of Pyridazine Derivatives. XII. Reaction of Amino-3 (2H) pyridazinone Derivatives with Tosyl Chloride

Abstract

Reactions of 4-amino-6-methoxy-(I), 4-amino-3 (2H) pyridazinone (II) and 3-methoxy-4-amino-6 (1H) pyridazinone (VIII) with tosyl chloride in pyridine were investigated. 4-Amino-3, 6-dimethoxypyridazine (XV) was also allowed to react with tosyl chloride in pyridine andN¹-(3, 6-dimethoxy-4-pyridazinyl-(XVI), N¹-(3-oxo-6-methoxy-2, 3-dihydro-5-pyridazinyl)-p-toluenesulfonamide (XVI-) and 2Ip-toluenesulfonyl-5-amino-6-methoxy-3 (2H) pyridazinone (X) were isolated. Consideration was made on the mechanism of the formation of X.