Heterocycles from Nitrile Oxides. 3. 1,2,4-Oxadiazol-5(4H)-ones
The reaction of nitrile oxides with potassium cyanate gives 3-aryl-1,2,4-oxadiazol-5(4H)-ones (5).These heterocycles are also obtained by cyclization of the corresponding O-carbethoxyamidoximes (7) with sodium ethoxide.
Hussein, Ahmad Q.
p. 127 - 128
(2007/10/02)
CYCLIZATION OF C- AND O-ACYL DERIVATIVES OF p-TOLUAMIDE O-ACETOACETYLOXIME
Reaction of p-toluamide O-acetoacetyloxime (1) with acyl chloride (2) in the presence of basic catalyst gave the corresponding O- and C-acyl derivatives (3 and 4).Cyclization of 3 afforded 5-(2-acyloxypropenyl)-3-(p-tolyl)-1,2,4-oxadiazole derivatives (6)