Chemistry of Azido Quinones. Cyanophenols from 4-Alkynyl-3-azido-1,2-benzoquinones

Article abstract of DOI:10.1021/jo00388a034

4-Alkynyl-3-azido-6-chloro-5-ethoxy-1,2-benzoquinones are shown to undergo thermolysis to (2-alkynyl-2-cyanoethenyl)ketenes.These conjugated ketenes undergo intramolecular cyclization to zwitterionic intermediates that proceed to highly substituted 4-cyanophenols via inter- or intramolecular trapping by nucleophilic attack at the aryl cation site.The mechanism and scope of these unusual transformations are discussed.