Bazı N-substitue amidoksimler ve 3,4- disubstitue A2-1,2,4-oksadiazolin-5-on`ların sentezi

Abstract

Asethidroksamik asit klorürün benzilaminle reaksiyonundan N-benzil- asetamidoksim ©İde edildi. N-benzilasetamidoksimin etil kloroformatla reaksiyonundan 3-metil-4-benzil- A -1, 2, 4- oksadiazolin-5-on bileşiği elde edildi. Bu reaksiyonda yan ürün olarak N-benzilasetamidoksim hid- roklorürü ele geçti. Piridin hidroksamik asit klorür hidroklorürlerinin primer aminler le reaksiyonundan N-substitue piridin karboksamidoksimler elde edildi. N`substitüe piridin karboksamidoksimlerin etil kloroformatla reaksiyo- nundan 3-piridil-4-substitue- A -1, 2, 4-oksadiazolin-5-onlar leldd edildi.

The reaction of aliphatic aldehyde oximes with chlorine gives aliphatic hydroxamic acid chlorides. The reaction of pyridine aldehyde oximes with chlorine also gives pyridine hydroxamic acid chlorides. N-Substituted amidoximes are obtained from the reaction of hydroxamic acid chlorides with primary amines.,N- Alky 1 amidoximes react with ethyl chloroformate in chloroform or benzene and give 3,44dialkyl- A -1, 2,4- oxadiazolin-5-one. N-Alkyl pyridine carboxamide oximes are obtained from the reactions of pyridine hydroxamic acid chloride hydrochlorides with primary amines. The reaction of N-alkyl pyridine carboxamide oximes with ethyl chloroformate in chloroform or in benzene also gives 3-pyridyl-4- alky 1- A - 1» 2, 4- oxadiazolin-5-ones. In our work, first acetaldehyde oxime and acethydroxamic `'Jdcid chloride were prepared. The reaction of acethydroxamic acid chloride with benzylamine gave N-benzyl-acetamidoxime. This compound was treated 2 with ethyl chloroformate in toluene and gave 3-methyl-4-benzyl- A 1 > 2, 4-oxadiazolin-5-one. The structure of this compound was determined ' yby` 3 its ir, nmr and micro analysis. At the second stage of our work, we reacted pyridine hydroxamic acid chloride hydrochlorides with primary amines and i' aöbfediiied' ';_. i N-substituted pyridine carboxamide oximes. The substituents were n-propyl, n-butyl, phenyl and benzyl. At the last stage of our work, we reacted some of 'these: new N-substituted pyridine carboxamide. oximes with ethyl chloroformate to investigate the occurrence of cyclization reaction. When the; reaction was run in toluene at the boiling point it proceeded slowly and gave a mixture of O-carbethoxy-N-substituted ;:.` iriyridlne carboxamide oximes and cyclization product. However, in xylene the reaction was completed and gave pure yields of cyclization products: 2 l 3-pyridyl-4-alkyl (or aryl)- A +1» 2, 4-oxadiazolin-5-ones.