138723-84-9Relevant articles and documents
Electrooxidative Cyclization of N-Acylhydrazones of Aldehydes and Ketones to Δ3-1,3,4-Oxadiazolines and 1,3,4-Oxadiazoles
Chiba, Toshiro,Okimoto, Mitsuhiro
, p. 1375 - 1379 (1992)
The electrolytic oxidation of ketone N-acylhydrazones (1) in methanolic sodium acetate induced their intramolecular cyclization to the corresponding 2-methoxy-Δ3-1,3,4-oxadiazolines 3.The thermal stability of a given oxadiazoline and what products were formed by its thermal decomposition was found to depend on the natures of the substituents at C-2.Thus, 2-methoxy-2-phenyloxadiazolines preferentially yielded oxiranes 5, whereas 2-alkyl-2-methoxyoxadiazolines preferentially gave enol ethers 6. 2,2-Dimethoxyoxadiazolines decomposed to the parent ketones and many unidentified products.The electrolytic oxidation of aldehyde N-acylhydrazones 2 gave 2,5-disubstituted 1,3,4-oxadiazoles 4.The oxidative cyclization of the N-benzoylhydrazones of aliphatic aldehydes gave especially high yields of the corresponding heterocycles.
Hypervalent Iodine Oxidation of N-Acylhydrazones and N-Phenylsemicarbazone: An Efficient Method for the Synthesis of Derivatives of 1,3,4-Oxadiazoles and Δ3-1,3,4-Oxadiazolines
Yang, Rui-Yang,Dai, Li-Xin
, p. 3381 - 3383 (2007/10/02)
The oxidation of ketone N-acylhydrazones 1 by phenyliodine(III) diacetate (PIDA) in alcohol gave 2-alkoxy-Δ3-1,3,4-oxadiazolines 4 in excellent yields, while the oxidative cyclization of aldehyde N-acylhydrazone 2 by PIDA in methanolic sodium acetate gave 2,5-disubstituted 1,3,4-oxadiazoles in good yields.The oxidation of acetone 4-phenylsemicarbazone afforded 2-(N-phenylimino)-Δ3-1,3,4-oxadiazoline in excellent yield.
