Annelated, chiral π-conjugated systems: Tetraphenylenes and helical β-oligothiophenes

Compounds with highly annelated, chiral π-systems, such as tetraphenylenes and [n]helicenes, are known to possess strong chiral properties and high configurational stability, which are prerequisites for many chiral materials. This account describes the unfolding story about our research on the synthesis and X-ray crystallographic characterization of functionalized nonracemic tetraphenylenes and helical β-oligothiophenes, as well as related [n]helicene derivatives. 1 Introduction 1.1 Riley' s Three-Dimensional Graphite 1.2 Annelated Helical β-Oligothiophenes: Carbon-Sulfur [n]Helicenes 2 Tetraarylenes 2.1 Double Helical Octaphenylene 2.2 Biphenylene Dimer 2.3 Enantiopure Tetranaphthylene: Binaphthyl Dimer 2.4 Asymmetric Synthesis of Tetraphenylenes: Greek Cross Dodecaphenylene 3 Synthesis of Annelated Helical β-Oligothiophenes 3.1 [7]Helicene 3.2 [7]Helicene: McMurry Reaction 3.3 [11]Helicene 3.4 Toward [n]Helicenes with n >11: Progress Report 4 Discovery of Conjoined Double Helicenes 5 Future Directions.