90701-75-0Relevant academic research and scientific papers
The Thermolysis of Polyazapentadienes. Part 3. Cyclisation of C-Methyl-1,2,5-triazapentadienes and Related Compounds: The Role of an Intermediate Spirodienyl Radical
McNab, Hamish
, p. 371 - 376 (2007/10/02)
A series of C-methyl-1,2,5-triazapentadienes and 2,5-diaza-1-oxapentadienes are prepared from pyruvaldehyde phenylhydrazones and oxime anils respectively.The 4-methyl derivatives show E/Z isomerism about the 4,5-double bond.Pyrolysis of the 5-phenyl derivatives (1), (3), (5), (7), and (10) causes cyclisation to 2-methylquinoxaline, though 2-phenyliminopropanonitrile is obtained from the oxime ester (9).Pyrolysis of the 5-p-tolyl derivatives (2), (4), (6), (8), and (11) qives mixtures of 2,6- and 2,7-dimethylquinoxaline.There are formed predominantly by the rearrangement reaction which involves the spirodienyl radical (19), but also by direct cyclisation of the iminyl radicals (17) and (18).
