Thermal fragmentation and rearrangement of N-aryl-2-furamide oximes I

Abd El-Aal M Gaber, Hussni A.

Abstract

Thermolysis of N-aryl-2-furamide oximes 1a-c (R=, H, CH3 and Cl) under nitrogen gives rise to benzimidazoles as the major products (37-50%), in addition to 2-furonitrile, arylamines, 2-furoic acid, phenols, 2-furanilides, 2- (furan-2-yl)benz- oxazoles and carbazoles. In the presence of naphthalene, thermolysis of 1a gave a- and b- naphthols (20%) beside the previous products. Also pyrolysis of 1a in boiling tetralin lead to the formation of 1- hydroxytetralin, a-tetralone and 1,1'-bitetralyl as the major products.The isolated products have been interpreted in the terms of a free radical mechanism involving the homolysis of N-O and/or C-N bonds.