1, 2, 4-Oxadiazoles from cycloreversions of oxadiazabicyclo [3.2. 0] heptenes: 1-azetines as thiocyanate equivalents

K Hemming, MN Khan, PA O'Gorman, A Pitard

Index: Hemming, Karl; Khan, Musharraf N.; O'Gorman, Paul A.; Pitard, Arnaud Tetrahedron, 2013 , vol. 69, # 4 p. 1279 - 1284

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Citation Number: 12

Abstract

1, 3-Dipolar cycloaddition of nitrile oxides to 4-aryl-2-alkylthio-1-azetines gave a series of oxadiazabicyclo [3.2. 0] heptenes as single diastereoisomers. Heating these cycloadducts in toluene resulted in an overall [2+ 2]-cycloreversion to give 5-alkylthio-3-aryl-1, 2, 4- oxadiazoles. In this process, the 1-azetine behaves as a thiocyanate equivalent. When the nitrile oxide substituent was 2-azidobenzene, the azide could be converted into a 1, 2, 3- ...