Studies on the Synthesis of Acetoacetanilide Derivatives

Acetoacetanilide 유도체 합성

Bromination of acetoacteanilide in non-polar medium gives the r-brominated derivative. This unexpected result may be due to the steric hinderance during the enolization of the substrate. The structure of r-bromoacetoacetanilide can be assigned on the basis of its 1H NMR spectrum. Additional evidence is provided by making derivatives, whick proceed without skeletal rearrangements. Structural similarity of 2-(N-phenylcarbamoyl)methylene-1,4-oxathiane with carboxin which is used as a potent fungicide prompted our investigation of the 1,4-oxathiane synthesis. It is prepared from the reaction of r-bromoacetoacetanilide with mercaptoethanol followed by acidic dehydration in high yield.

Acetoacetanilide를 브롬화한 결과 예상한 ${\alpha}$-bromo 유도체가 얻어지지 않고, r-bromo 유도체가 얻어졌다. 이것을 mercaptoethanol과 반응시켜 sulfide 유도체를 만든다음, 산성하에서 고리화시킨 결과 2-(N-phenylcarbamoyl)methylene-1,4-oxathiane이 좋은 수율로 얻어졌다. 이 물질은 살균제 농약으로 널리 사용되고 있는 carboxin과 그 구조가 매우 유사하므로 이 물질의 biological activity는 흥미있는 과제가 될 것이다.