Aliphatic Hydrocarbons

Abstract The aliphatic hydrocarbons discussed in this chapter are open‐chain compounds that may be saturated or unsaturated. The saturated compounds, known as paraffin hydrocarbons or alkanes, include methane and its homologs having the empirical formula C n H 2 n +2 . The unsaturated compounds fall into a number of homologous series: ( 1 ) those containing one double bond (ethene and its homologs) and having the formula C n H 2n are known as olefins or alkenes; ( 2 ) those containing one triple bond (acetylene and its homologs) are called acetylenes or alkynes and have the formula C n H 2 n −2 ; ( 3 ) those having two double bonds (allene, 1,3‐butadiene, and 1,4‐pentadiene represent three types) are diolefins or alkadienes and also have the formula C n H 2 n −2 ; ( 4 ) those having a large number of double or triple bonds or both double and triple bonds are named in analogous fashion as alkatrienes , alkatetraenes , alkadiynes , alkenynes , and alkadienynes . Aliphatic hydrocarbons have the potential to act as asphyxiants and central nervous system (CNS) depressants. Serious toxic effects of aliphatic hydrocarbons include asphyxia and chemical pneumonitis for many of the compounds in this category. There is evidence in humans of axonal neuropathy for n ‐hexane and cancer for 1,3‐butadiene. The hepatic and renal systems can be impacted by target organ toxicity, some of which may not be relevant to human.