Synthesis and Characterization of Subporphyrins with Dendritic Carbazole Arms

A series of novel dendritic carbazole‐functionalized subporphyrins, T(Cz‐G n )SubPs ( n = 1–3), have been synthesized from pyridine–tri(pyrrol‐1‐yl)borane and the corresponding aldehydes. This study has demonstrated that intramolecular energy transfer from the carbazole dendron to the subporphyrin core occurs with a high efficiency which decreases with increasing dendron generation, in accord with the Förster mechanism of energy transfer. In addition, the carbazole dendron can lead to a blueshift of the absorption and emission bands of the subporphyrin core. The light‐harvesting abilities of these compounds increase with increasing generation. Meanwhile, these dendritic macromolecules emit intense yellow‐green light and may be good candidates for photonic devices. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)