Synthesis and Chiroptical Properties of a Saddle-Shaped Quadruple Helicene with a Cyclooctatetrapyrrole Core

A quadruple helicene with a cyclooctatetrapyrrole core was synthesized via a simple Ullmann reaction. Its single-crystal structure exhibits a saddle shape. The compound shows fluorescence emission with λem = 575 nm and good chiroptical properties, including a dissymmetric absorption factor (|gabs|) of 5.84 × 10–3 and a dissymmetric emission factor (|glum|) of 1.21 × 10–2.