The stepwise syntheses of germa[N]pericyclynes, including [5]pericyclynes, and their characterization are described. The yields of germa[4] and [8]pericyclynes were improved significantly compared to those obtained in previous studies. The routes reported herein afforded the novel germa[5] and [10]pericyclynes, which were characterized by X-ray crystallography, UV-Vis spectroscopy, and fluorescence emission spectroscopy. A unique fluorescence emission was observed for the large germa[10]pericyclyne ring.
![Graphical abstract: Stepwise synthesis and characterization of germa[4], [5], [8], and [10]pericyclynes](http://hg.y866.cn/compound/lib/scimg/usr/1/C5DT01411E.jpg)