Ibrahim El-Sayed El-Kholy

Pyrone series. Part X. Reactivity of 4,5,6-triaryl-2-pyrones and the corresponding thio-analogues

Several 4,5,6-triaryl-3-bromo-2-pyrones have been prepared and converted by alcoholic alkali into furancarboxylic acids. These 3-bromo-2-pyrones and some triaryl-2-pyrones when treated with phosphorus pentasulphide gave the corresponding 2-thiopyrones, from which 1-methyl-2-thiopyridones, 2-pyrone phenylhydrazones, open-chain thioamides, and 1-thio-2-pyrones were obtained. 2-Pyridones, 1-amino-2-pyridones, 1-methyl-2-pyridones, 2-methoxypyridines, and 1-methoxy-2-pyridones have also been prepared. The i.r. and u.v. spectra of these compounds are recorded.

Pyrone series. Part IX. Some reactions of 1-amino-4,5,6-triaryl-2-pyridones

Six-membered copper bis-(1-salicylideneamino-4,5,6-triaryl-2-pyridone) complexes and a number of 1-arylidene-amino-, 1-phthalimido-, 1-succinimido-, and 1-maleimido-4,5,6-triaryl-2-pyridones have been prepared. Of these, the 1-arylideneamino-derivatives are not hydrolysed by hydrochloric acid, but copper chloride or 2,4-dinitrophenylhydrazine catalyses the formation of the free amine and the corresponding aldehyde.

Pyrone series. Part XI. Reactivity of 4,6-diaryl-2-pyrones and cyclopropane derivatives obtained from 2-pyrazolines

4,6-Diaryl-2-pyrones and ethyl 2-aroyl-3-arylcyclopropanecarboxylates have been prepared from 2-pyrazolines. The structure of the pyrones was established by fission with alkali. Treatment of the cyclopropane derivatives with hydrazine hydrate gave diazabicycloheptenones, from which N-acetyl and N-methyl derivatives were prepared. The 2-pyrazolines were also converted into pyrazine derivatives (III), which gave N-oxides. The pyrones could be converted into 2-pyridones, 1-methyl-2-pyridones, 2-methoxypyridines, 1-amino-2-pyridones, 2-thiopyrones, 1-methyl-2-thiopyridones, and 1-thio-2-pyrones. The structures assigned to the products were established by u.v. and i.r. spectroscopy.