1,4-Cycloheptadiene is a highly

flammable A combustible material is something that can burn (i.e., ''combust'') in air. A combustible material is flammable if it ignites easily at ambient temperatures. In other words, a combustible material ignites with some effort and a flammable mat ...

cycloalkene A cycloalkene or cycloolefin is a type of alkene hydrocarbon which contains a closed ring of carbon Atom, atoms and either one or more double bonds, but has no Aromaticity, aromatic character. Some cycloalkenes, such as cyclobutene and cyclopentene ...

that occurs as a colorless clear liquid. It can form a yellow complex with palladium.

References

Cycloalkenes Dienes Seven-membered rings {{Hydrocarbon-stub