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Luis Cuellar

What are skew positions in the conformation of cyclohexane?

Brittany Roma  Follow

It also appeared that the term skew position (or symmetrical skew) was used to refer to the chair conformation in some early research papers. I found two papers published in the early 1960s where the term was used in that way.

...with the growing interest in the family of cyclohexane conformations which include the boat and the symmetrical skew as extreme cases...

The symmetrical skew cyclohexane with neither bond length nor bond angle distortion, alternatively referred to as the stretched conformation or the "halfrotated" form, is shown by the numerical analysis to have dihedral angles of 33.1, 33.1, and 70.67", and not the 30, 30, 60" values quoted, for instance, by Klyne and Prelog (1960).

The skew conformation has the minimum energy of the flexible form...

References

Angyal, S. J., & Hoskinson, R. M. (1962). 578. Cyclitols. Part XIII. The conformation of cyclic diketals: the skew conformation. Journal of the Chemical Society (Resumed), 2991-2995.

Bottomley, G. A., & Jefferies, P. R. (1961). The Dihedral Angles of Cyclohexane. Australian Journal of Chemistry, 14(4), 657-659.

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Brent Meeker  Follow

I googled "conformation skew staggered" and found:

The infinite number of possible intermediate conformations between the two extreme conformations are referred to as skew conformations. In these conformations, hydrogen atoms are closer than in staggered but away than in eclipsed conformation.enter image description here

Source: https://knowledgebin.org/entry/stereochemistry-7/

Then I googled "torsion angles boat chair conformation" and found:

enter image description here

Source: Libretexts

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