Cycloalkane

In organic chemistry, the cycloalkanes (also called naphthenes, but distinct from naphthalene) are the monocyclic saturated hydrocarbons. In other words, a cycloalkane consists only of hydrogen and carbon atoms arranged in a structure containing a single ring (possibly with side chains), and all of the carbon-carbon bonds are single. The larger cycloalkanes, with more than 20 carbon atoms are typically called cycloparaffins. All cycloalkanes are isomers of alkenes. The cycloalkanes without side chains are classified as small (cyclopropane and cyclobutane), common (cyclopentane, cyclohexane, and cycloheptane), medium (cyclooctane through cyclotridecane), and large (all the rest). Besides this standard definition by the International Union of Pure and Applied Chemistry (IUPAC), in some authors' usage the term cycloalkane includes also those saturated hydrocarbons that are polycyclic. In any case, the general form of the chemical formula for cycloalkanes is CnH2(n+1−r), where n is the number of carbon atoms and r is the number of rings. The simpler form for cycloalkanes with only one ring is CnH2n. IUPAC nomenclature Alkanes Unsubstituted cycloalkanes that contain a single ring in their molecular structure are typically named by adding the prefix "cyclo" to the name of the corresponding linear alkane with the same number of carbon atoms in its chain as the cycloalkane has in its ring. For example, the name of cyclopropane (C3H6) containing a three-membered ring is derived from propane (C3H8) - an alkane having three carbon atoms in the main chain. The naming of polycyclic alkanes such as bicyclic alkanes and spiro alkanes is more complex, with the base name indicating the number of carbons in the ring system, a prefix indicating the number of rings ( "bicyclo-" or "spiro-"), and a numeric prefix before that indicating the number of carbons in each part of each ring, exclusive of junctions. For instance, a bicyclooctane that consists of a six-membered ring and a four-membered ring, which share two adjacent carbon atoms that form a shared edge, is [4.