Abstract
A real-time analysis of the flash-vacuum pyrolysis products of 1-vinyl-, 1-(2-methylprop-1-enyl)-, and 1-styryl-benzotriazole (
3
), (
16
), and (
18
) has been performed by tandem mass spectrometry. In the 500-700 °C temperature range, these compounds lose nitrogen yielding the
N
-phenylketenimines (
14
), (
17
), and (
19
), respectively. At higher pyrolysis temperatures (
3
) gives indole (
4
)
via
isomerization of (
14
), whereas from (
16
) the secondary products of (
17
) are benzene and methacrylonitrile. In a preparative pyrolysis of (
18
) at 800 °C 2- and 3-phenylindole (
9
) and (
10
) respectively, have also been detected.