INFIQC 05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
artículos
Título:
Flash Vacuum Pyrolysis (FVP) of Some Hexahydroquinazolin-4(1H)-ones
Autor/es:
W. J. PELÁEZ; Z. SZAKONYI; F. FÜLOP; G. I. YRANZO
Revista:
TETRAHEDRON
Editorial:
Elsevier
Referencias:
Año: 2008 vol. 64 p. 1049 - 1057
ISSN:
0040-4020
Resumen:
Some cis/trans 2-thioquinazolin-4-ones and their 2,4-dione analogs were subjected to flash vacuum pyrolysis. The cis and trans thio compounds reacted at lower temperatures than the cis and trans dioxo analogs, showing a lower thermal stability. All of these compounds afforded similar reactions: ring opening to the corresponding iso(thio)cyanate, the loss of H. and .NCS to form three isomeric cyclohexadienes, and then aromatization to form the corresponding benzamide. The cis dioxo compound also underwent a competitive retro Diels Alder (RDA) reaction, to form 3-phenylpyrimidine-2,4(1H,3H-dione(3-phenyluracil)) and butadiene. Kinetic measurements for the ring opening reaction supported a concerted b-elimination as the most probable mechanism.
