Metal Phthalocyanine−Fullerene Dyads: Promising Lamellar Columnar Donor−Acceptor Liquid Crystal Phases

Liquid crystal (LC) shape‐amphiphiles with a disc tethered to a fullerene have been intensely studied for the application in photovoltaics, and helical nanosegregation of C$_{60}$ has been claimed around the π‐stacking disks based on X‐ray results. The most promising materials reported to date have been resynthesized and studied comprehensively by XRS, density measurements, modelling, and electron density reconstruction. In contrast to previous reports, the results indicate that metal phthalocyanine−fullerene mesogens pack in lamellar columnar phases with p2gm symmetry. Fullerenes assemble in layers and are flanked by phthalocyanine columns, thus explaining the balanced charge carrier mobility of electrons and holes. Such variable donor−acceptor structures are promising for organic electronic applications

Metal Phthalocyanine−Fullerene Dyads: Promising Lamellar Columnar Donor−Acceptor Liquid Crystal Phases

Liquid crystal (LC) shape‐amphiphiles with a disc tethered to a fullerene have been intensely studied for the application in photovoltaics, and helical nanosegregation of C$_{60}$ has been claimed around the π‐stacking disks based on X‐ray results. The most promising materials reported to date have been resynthesized and studied comprehensively by XRS, density measurements, modelling, and electron density reconstruction. In contrast to previous reports, the results indicate that metal phthalocyanine−fullerene mesogens pack in lamellar columnar phases with p2gm symmetry. Fullerenes assemble in layers and are flanked by phthalocyanine columns, thus explaining the balanced charge carrier mobility of electrons and holes. Such variable donor−acceptor structures are promising for organic electronic applications

π-π Catalysis Made Asymmetric—Enantiomerization Catalysis Mediated by the Chiral π-System of a Perylene Bisimide Cyclophane

Enzymes actuate catalysis through a combination of transition state stabilization and ground state destabilization, inducing enantioselectivity through chiral binding sites. Here, we present a supramolecular model system that employs these basic principles to catalyze the enantiomerization of [5]helicene. Catalysis is hereby mediated not through a network of functional groups but through π-π catalysis exerted from the curved aromatic framework of a chiral perylene bisimide (PBI) cyclophane offering a binding pocket that is intricately complementary with the enantiomerization transition structure. Although transition state stabilization originates simply from dispersion and electrostatic interactions, enantiomerization kinetics are accelerated by a factor of ca. 700 at 295 K. Comparison with the mesocongener of the catalytically active cyclophane shows that upon configurational inversion in only one PBI moiety the catalytic effect is lost, highlighting the importance of precise transition structure recognition in supramolecular enzyme mimics

π−π\pi-\pi Catalysis Made Asymmetric—Enantiomerization Catalysis Mediated by the Chiral π\pi‐System of a Perylene Bisimide Cyclophane

Enzymes actuate catalysis through a combination of transition state stabilization and ground state destabilization, inducing enantioselectivity through chiral binding sites. Here, we present a supramolecular model system which employs these basic principles to catalyze the enantiomerization of [5]helicene. Catalysis is hereby mediated not through a network of functional groups but through $\pi-\pi$ catalysis exerted from the curved aromatic framework of a chiral perylene bisimide (PBI) cyclophane offering a binding pocket that is intricately complementary with the enantiomerization transition structure. Although transition state stabilization originates simply from dispersion and electrostatic interactions, enantiomerization kinetics are accelerated by a factor of ca. 700 at 295 K. Comparison with the meso-congener of the catalytically active cyclophane shows that upon configurational inversion in only one PBI moiety the catalytic effect is lost, highlighting the importance of precise transition structure recognition in supramolecular enzyme mimics