Nonaromatic compounds are hydrocarbon compounds that do not have a conjugate ring system, such as naphthalene, benzene or imidazole. They are sometimes referred to as aliphatic compounds.
Nonaromatic compounds do not have a loop for pi electron. Therefore, compounds with molecules containing one or more of a non-aromatic rings are collectively categorized as nonaromatic compounds. Nonaromatic compounds can be saturated, joined with single bond or unsaturated joined by double bond. Additionally, unsaturated aliphatic compounds can also have triplet bonds. Some nonaromatic compounds are flammable, which makes it possible for some hydrocarbon, such as methane, to be used as fuels in Bunsen burners and acetylene in welding.