View source for Organic:atropisomerism

Atropisomerism is the distinction between two molecules that arises due to restricted rotation about a single bond, usually due to the high steric demand removing the usually free rotation.  First found in biaryl systems in the 1920's, this phenomenon is also commonly found in the "restricted rotation of substituted aromatic rings within macrocyclic structures"<ref>Lloyd-Williams, P.; Giralt, E. Chem. Soc. Rev., 2001, 30, 145</ref>, as is the case with the taxol precursor the Organic Module.

Atropisomerism is a subclass of the wider field of axial chirality, which also contains types of isomerism such as the handedness of helices.

== External links ==
* [http://www.rsc.org/ej/CS/2001/b001971m.PDF Lloyd-Williams, P.; Giralt, E. Chem. Soc. Rev., 2001, 30, 145 ]
* [http://en.wikipedia.org/wiki/Atropisomerism More expansive Wiki page on the effect]

== References ==
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