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The boat and twist-boat conformations, as said, lie along a continuum of zero angle strain. If there are substituents that allow the different carbon atoms to be distinguished, then this continuum is like a circle with six boat conformations and six twist-boat conformations between them, three "right-handed" and three "left-handed".
The boat conformation (C, 6.9 kcal/mol, C 2v symmetry) is a local energy maximum for the interconversion of the two mirror image twist-boat conformers, the second of which is converted to the other chair confirmation through another half-chair. At the end of the process, all axial positions have become equatorial and vice versa.
There is a peak/local maximum at the boat conformation (C), and there are valleys/local minimums at the twist-boat conformations (B). In addition, cyclohexane conformations can be used to indicate if the molecule has any 1,3 diaxial-interactions which are steric interactions between axial substituents on the 1,3, and 5 carbons. [8]
While simple molecules can be described by these types of conformations, more complex molecules require the use of the Klyne–Prelog system to describe the different conformers. [6] More specific examples of conformations are detailed elsewhere: Ring conformation Cyclohexane conformations, including with chair and boat conformations among others.
The chair and twist-boat are energy minima and are therefore conformers, while the half-chair and the boat are transition states and represent energy maxima. The idea that the chair conformation is the most stable structure for cyclohexane was first proposed as early as 1890 by Hermann Sachse, but only gained widespread acceptance much later.
English: Cyclooctane twist boat-chair conformation. Source for name and structure: PW Pakes, TC Rounds, HL Strauss (1981). Conformations of cyclooctane and some related oxocanes. The Journal of Physical Chemistry. 85 (17): 2469–2475.
Twistane (IUPAC name: tricyclo[4.4.0.0 3,8]decane [2]) is an organic compound with the formula C 10 H 16. [3] It is a cycloalkane and an isomer of the simplest diamondoid, adamantane, and like adamantane, is not very volatile.
Hendrickson noted that "cyclooctane is unquestionably the conformationally most complex cycloalkane owing to the existence of many conformers of comparable energy". The boat-chair conformation (below) is the most stable form. [4] This conformation was confirmed by Allinger and co-workers. [5] The crown conformation (below) [6] is