Macrocyclic system 1 was synthesized using an approach similar to a previously published procedure for macrocyclic motors (Figure ). However, different to earlier macrocyclic motors from our group, motor 1 incorporates the asymmetric biaryl moiety in ortho-position to the sulfur atom, which gives rise to a 90° angle of the biaryl axis with respect to the photoisomerizable double bond. Introduction of the bromide at this position in the precursor HTI was achieved by an unexpected halogen migration from para-to ortho-position during the intramolecular Friedel-Crafts acylation of precursor 2. The resulting benzothiophenone 3 was condensed with indanone 4 to form the corresponding brominated HTI 5. After attachment of a short polyethylene glycol (PEG) chain 6 via an azide-alkyne Huisgen click-reaction to yield 7, an intramolecular Suzuki cross-coupling leads to the macrocyclized HTI 8. Final oxidation of the sulfur to the corresponding sulfoxide 1 introduces the chiral information necessary for unidirectional motor rotation. With oxidation of the sulfur, two molecular half-spaces are established relative to the position of the sulfoxide oxygen with respect to the plane of the thioindigo fragment. We arbitrarily termed the half space containing the sulfoxide oxygen as top half-space and the opposite as bottom half-space (Figure ). For detailed synthetic information see the Supporting Information chapter 2. Taking together all stereo-elements present in 1, eight diastereomers are possible for one configuration of the sulfoxide stereo-center (Figure ).