81467-55-2Relevant academic research and scientific papers
Cyclization of O-Acetoacetylbenzamide Oxime Derivatives
Tabei, Katsumi,Kawashima, Etsuko,Takada, Toyozo,Kato, Tetsuzo
, p. 336 - 340 (2007/10/02)
O-Acetoacetylbenzamide oxime derivatives (2) were prepared from benzamide oxime derivatives (1) and diketene at low temperature in almost quantitative yields.Cyclization of 2 in the presence of a strong base proceeded with elimination of acetone to afford 3-aryl-1,2,4-oxadiazolin-5-one derivatives (4) in 77-95percent yields.However, in the cases of the o-, m-, and p-nitrobenzamide oxime derivatives (2f-h), the reaction proceeded with dehydration even in the presence of a strong base to afford 5-acetonyl-3-aryl-1,2,4-oxadiazole derivatives (3f-h) in moderate yields.Possible mechanisms of these cyclization are discussed.
