Topological rubber glove

Flapan, E Seeman, N.C. (1995) A topological rubber glove obtained from a synthetic single stranded DNA molecule, J. Chem. Soc., Chem. Commute, 2249-2250. 

The existence of topological rubber gloves proves that the absence of rigidly achiral presentations is a necessary but not a sufficient condition for topological chirality. 

Figure 29. Enantiomorphous conformations of a [2]catenane that is a topological rubber glove.113 Unlabeled vertices represent carbon atoms, and hydrogen atoms are suppressed for clarity. The enantiomorphs are related by the mirror plane (m) and are interconverted by rotation of the 1,5-dioxynaphthalene moiety about the C-0 bonds (arrows).

Merrifield, R. E., and Simmons, H. E. (1989). Topological Methods in Chemistry, Wiley, New York. Chambron, J.-C., Sauvage, J.-R, and Mislow, K. "A Chemically Achiral Molecule with No Rigidly Achiral Presentations." /. Am. Chem. Soc., 119,9558 (1997). The "topological rubber glove". 

Topological isomerism in simple catenaries. A. A kind of "positional" isomerism that can occur in a [3]catenane witli two different kinds of ring. B. A more subtle isomerism that involves "oriented" rings, and a chemical example. C. The "toplogical rubber glove", a pair of enantiomers that can interconvert readily without ever going through an achiral conformation. 

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