Straightforward Access to Multifunctional π-Conjugated P-Heterocycles Featuring an Internal Ylidic Bond

We report the straightforward one-pot synthesis of novel 5- or 6-membered P-heterocycles featuring an internal ylidic bond: P-containing acenaphthylenes and phenanthrenes. The stability of the compounds tolerates post-functionalization through direct arylation to introduce electron-rich/poor substituents and the synthetic strategy is also compatible with the preparation of more elaborate polyaromatic scaffolds such as acenes and helicenes. Using a joint experimental (X-ray analysis, optical and redox properties) and theoretical approach, we perform a full structure-property relationships study on these new platforms. In particular, we show that molecular engineering allows not only tuning their absorption/emission across the entire visible range but also endowing them with chiroptical or non-linear optical properties, making them valuable dyes for a large panel of photonic or opto-electronic applications.

Automated summary

We report a straightforward synthesis method for novel P-heterocycles. These compounds exhibit good stability and can be post-functionalized with different substituents. They are also suitable for the preparation of more complex polyaromatic scaffolds. Our study shows that molecular engineering can not only tune the optical properties of these compounds but also impart them with special optical properties.