Abstract

A dicationic 6helicene congener captured on the racemization pathway in its saddle-shaped geometry is introduced. Synthesis, structure, resolution, and dynamic properties of this chiral 6saddlequat in-between and its highly stereocontrolled transformation into enantiopure 6helquat are discussed and demonstrated. The dynamic aspects established by experiment and supported by detailed DFT-D calculations are presented visually in the form of a movie (electronic table-of-contents and electronic supplementary information). The title 6saddlequat was found to be an isolable chiral species on the entirely chiral enantiomerization pathway of a 6helquat that is discussed as an example of Mislow's "rubber glove" molecule. © The Royal Society of Chemistry 2011.