A novel acid-catalyzed rearrangement of n-aryl-n′-aryloxyureas to biphenyl derivatives. A [5,5]-rearrangement involving three heteroatoms.
作者:Yasuyuki Endo、Tohru Terashima、Koichi Shudo
DOI:10.1016/s0040-4039(01)81619-1
日期:1984.1
acid, N-phenyl-N′-phenoxyurea (1a) rearranges to N-(4′-hydroxy-2-biphenylyl)urea (2a) and N-carbamoyl-2-hydroxy-diphenylamine (3a). The rearrangement is an intramolecular reaction, and the transition state of the breakage of the N-O bond is deduced to be polarized in the form Nδ- --- Oδ+. The reaction is entirely new and constitutes a fundamental aromatic rearrangement.