The flow-vacuum pyrolysis of dibenzo [CH]8 hydrocarbons 2,3,4, and 5 a
re studied at 1 Torr and in the temperature range between 400 and 650-
degrees-C. The following new transformations have been observed: 2 rev
ersible 4, 2 --> 5, 3 --> 5, 3 reversible 4, 3 --> 2, 5 --> 11, the la
st three presenting analogies in the [CH]8 and/or benzo [CH]8 series.
A reaction mechanism is suggested.