General Information. BiCl3, BiBr3, BiI3 and hydrazine hydrate were obtained from Sigma-Aldrich. DMF-d7 was purchased from Sigma Aldrich. All other reagents were purchased from Fluorochem and Apollo Scientific and used without further purification. HPLC-grade dimethylformamide (DMF), acetonitrile (ACN), and tetrahydrofuran (THF) were purchased from Sigma-Aldrich for the photophysical analysis. Spectroscopic Measurements. H-NMR and C-NMR spectroscopy was performed either with AVANCE III 600 or Avance Neo 500 at room temperature. The chemical shifts  are given in parts per million (ppm) and referenced to DMSO-d6 (2.50 ppm in H-NMR and 39.52 ppm in C-NMR spectroscopy), CDCl3 (7.26 ppm in H-NMR and 77.16 ppm in C-NMR spectroscopy) and DMF-d7 (8.03, 2.92, 2.75 ppm in 1 H-NMR). All the samples for photophysical studies were prepared as stock solutions in DMF and further diluted in ACN and THF for the measurements.