Triangulane

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[2]Triangulane, the simplest triangulane compound, consists of a chain of two spiro-linked cyclopropane rings Spiro(2.2)pentane skeletal.svg
[2]Triangulane, the simplest triangulane compound, consists of a chain of two spiro-linked cyclopropane rings

A triangulane is a hydrocarbon consisting exclusively of a series of spiro-linked cyclopropane rings. [1]

Triangulanes are named according to the rules of systematic nomenclature for spiro compounds. [2] The pattern of their common names is "[n]triangulane", where n is the number of cyclopropane units. The simplest such chemical, [2]triangulane, is named spiro[2.2]pentane by systematic nomenclature. Chains consisting of four or more cyclopropane units—[4]triangulane and higher—can form chiral helices. [1] This property is unusual for a molecule that contains no stereogenic atoms; the chiral nature is due to restricted mobility of the chain ends analogous to helicene molecules.

The rings can form a branched or cyclic patterns. For example, [3]rotane is a branched [4]triangulane; it consists of one additional cyclopropane attached to the central ring of a [3]triangulane chain. [3]

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References

  1. 1 2 Zefirov, Nikolai S.; Kozhushkov, Serge I.; Kuznetsova, T. S.; Kokoreva, O. V.; Lukin, K. A.; Ugrak, B. I.; Tratch, Serge S. (1990). "Triangulanes: stereoisomerism and general method of synthesis". J. Am. Chem. Soc. 112 (21): 7702–7707. doi:10.1021/ja00177a034.
  2. Moss, G. P. (1999-03-30). "Extension and revision of the nomenclature for spiro compounds". Pure and Applied Chemistry. 71 (3): 531–558. doi: 10.1351/pac199971030531 . ISSN   1365-3075.
  3. de Meijere, Armin; Kozhushkov, Sergei I.; Fokin, Andrey A.; Emme, Ingo; Redlich, Stefan; Schreiner, Peter R. (2003). "New structurally interesting cyclopropane derivatives. A world of wonders and surprises" (PDF). Pure Appl. Chem. 75 (5): 549–562. doi:10.1351/pac200375050549. S2CID   15320567.