An Efficient One-Pot Synthesis of 3-Aryl-5-(Dialkoxymethyl)-1,2,4-Oxadiazoles under Solvent-Free Conditions

Abstract

An efficient and simple synthesis of 3-aryl-5-(dialkoxymethyl)-1,2,4-oxadiazoles is described. The in situ prepared amidoximes from the reaction between nitriles and hydroxylamine are condensed with alkyl 2,2-dialkoxyacetates under solvent-free conditions to produce the title compounds in excellent yields.

An efficient synthesis and antimicrobial evaluation of 5-alkenyl- and 5-styryl-1,2,4-oxadiazoles

“…11 Moreover, 5-alkenyl-and 5styryl-1,2,4-oxadiazoles are actively employed in organic synthesis, including Michael addition reactions [12][13][14] , 1,3-dipolar cycloadditions 15,16 , Rh-catalyzed 17,18 or metal-free arylations. 19 Most of the traditional methods for the preparation of 1,2,4-oxadiazole, such as condensation of amidoximes with carboxylic acids and their derivatives or 1,3-dipolar cycloadditions of nitrile oxides to nitriles, [20][21][22][23] require harsh conditions (high temperature, microwave irradiation or high pressure). 24,25 These conditions pose a serious limitation for labile organic compounds, especially those containing C=C double bonds and typically yield multiple side-products along with low yields of target compounds.…”