A triangulane is a

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and hydrophobic, and their odors are usually weak or ...

consisting exclusively of a series of spiro-linked

cyclopropane Cyclopropane is the cycloalkane with the molecular formula (CH2)3, consisting of three methylene groups (CH2) linked to each other to form a ring. The small size of the ring creates substantial ring strain in the structure. Cyclopropane itself i ...

rings. Triangulanes are named according to the rules of systematic nomenclature for

spiro compound In organic chemistry, spiro compounds are compounds that have at least two molecular rings with only one common atom. The simplest spiro compounds are bicyclic (having just two rings), or have a bicyclic portion as part of the larger ring sy ...

s. The pattern of their

common names In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...

is " 'n''riangulane", where ''n'' is the number of cyclopropane units. The simplest such chemical, riangulane, is named spiro .2entane by systematic nomenclature. Chains consisting of four or more cyclopropane units— riangulane and higher—can form

chiral Chirality is a property of asymmetry important in several branches of science. The word ''chirality'' is derived from the Greek (''kheir''), "hand", a familiar chiral object. An object or a system is ''chiral'' if it is distinguishable from i ...

helices. This property is unusual for a molecule that contains no

stereogenic In stereochemistry, a stereocenter of a molecule is an atom (center), axis or plane that is the focus of stereoisomerism; that is, when having at least three different groups bound to the stereocenter, interchanging any two different groups cr ...

atoms; the chiral nature is due to restricted mobility of the chain ends analogous to

helicene In organic chemistry, helicenes are ortho-condensed polycyclic aromatic compounds in which benzene rings or other aromatics are angularly annulated to give helically-shaped chiral molecules. The chemistry of helicenes has attracted continuin ...

molecules. The rings can form a branched or cyclic patterns. For example, otane is a branched riangulane; it consists of one additional cyclopropane attached to the central ring of a riangulane chain.

References

Hydrocarbons Cyclopropanes Spiro compounds {{Hydrocarbon-stub