Gas‐phase pyrolysis in organic synthesis: A route for synthesis of cyanamides

Abstract

in Wiley InterScience (www.interscience.wiley.com).Pyrolysis of 1,7-di-[(E)-1-morpholinomethylidene]-and 1,7-di-[(E)-1-piperidino-methylidene]-4,6,10,12-tetramethylamino-2,8-dioxo-1,7-diaza-3,5,9,11-cyclododecatetraene-3,9-dicarbonitrile 6a,b afforded pyridone 10 in addition to cyanamides 11a,b. On the other hand, pyrolysis of 1-[E-(4-(E-3-cyano-4,6-dimethyl-2-oxopyridin-1(2H)-ylimino) methylpiperazin-1-yl] methylenamino-4,6-dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile 8 gave 1-amino-4,6-dimethyl-2-oxo-1,2-dihydropyridine-3-carbonitrile 13 as well as piperazine. The mechanism of pyrolysis and the effect of stereochemistry of pyrolyzed substrates on the nature of the pyrolysates are discussed.