Topological and Supramolecular Stereochemistry

Topologically, the triangle, circle, and square are all just closed loops (as long as we do not consider the corners of the triangle and square to be vertices). 

Interconversion of the enantiomers of 2-butanol can be accomplished by flexing and bending without crossing any bonds, and so the two enantiomers are topologically equivalent. 

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