The rearrangement of acetylene, benzene, ethane, ethylene, methane and naphthalene in a microwave discharge

The rearrangement of ethane, ethylene and methane (Group A) and of acetylene, benzene and naphthalene (Group B) was studied in a microwave discharge. Hydrogen was the major gaseous rearrangement product of Group A hydrocarbons with small amounts of low‐molecular weight hydrocarbons. No gases were detectable on rearrangement of Group B hydrocarbons. A film with a characteristic H/C ratio was the rearrangement product of any of the gases. All films took up additional hydrogen from a hydrogen discharge and approached a limiting H/C ratio of 1·6. Films with lower H/C ratios took up proportionally greater amounts of hydrogen. X ‐Ray and electron diffraction studies of the films showed that the films were amorphous. Other properties of the films produced from the two groups were markedly different. Infra‐red analyses indicated that the films from Group B were more unsaturated than those from Group A but neither set contained aromatic bonding. The films from Group B exhibited high concentrations of free spins. The results are consistent with a rearrangement mechanism which is independent of the type of bonding in the original hydrocarbon. The mechanism may involve CH.