Coumarin-embedded [5]helicene Derivatives: Synthesis, X-ray Analysis and Photoconducting Properties.

Two novel coumarin-embedded pi-extended [5]helicene derivatives (3a and 6a) have been strategically synthesized and characterized, and the structure of 3a was determined via single crystal X-ray analysis. Both of them exhibit green fluorescence in dichloromethane. In addition, molecule 3a can aggregate to form a large quantity of nanowires through the re-precipitation method. More importantly, the photoelectric conversion properties of 3a nanowire-C60 based films are much better than those of the thin film of bulk 3a-C60, indicating that the ordered nanostructures are a crucial factor for enhancing device performance. Two novel coumarin-embedded pi-extended [5]helicene derivatives (3a and 6a) have been strategically synthesized and characterized, and the structure of 3a was determined via single crystal X-ray analysis.