New chemistry of diazafulvenium methides: one way to pyrazoles

• Author(s): Melo, Teresa M. V. D. Pinho e ; Soares, Maria I. L. ; Gonsalves, António M. d'A. Rocha
• Date: 2006
• Persistent ID: http://hdl.handle.net/10316/5093
• Origin: Estudo Geral - Universidade de Coimbra
• Subject(s): Diazafulvenium methides; Vinyl-1H-pyrazoles; Pyrazolo[1,5-a]pyridines; Pyrazolo[1,5-a]pyrrolo[3,4-c]pyridine; [8[pi]+2[pi]] Cycloaddition; Sigmatropic shift
• Document Type: Article
• Language: English

Description

Diazafulvenium methides generated from the solution pyrolysis of pyrazolo[1,5-c][1,3]thiazole-2,2-dioxides participate in [8[pi]+2[pi]] cycloadditions giving pyrazolo[1,5-a]pyridine derivatives. 1-Methyl-diazafulvenium, generated under flash vacuum pyrolysis reaction conditions, undergoes an intramolecular sigmatropic [1,8]H shift giving 1-vinyl-1H-pyrazoles. http://www.sciencedirect.com/science/article/B6THS-4HR7298-7/1/af0dd8d679e7977f53bc0d4af9a5b688