The synthesis of BN-embedded tetraphenes and their photophysical properties

A series of intensely blue fluorescent BN-embedded tetraphene derivatives have been synthesized by the catalytic cyclization of BN-naphthalenes with alkynes. The BN-tetraphene can be selectively functionalized to give a substituted derivative via bromination followed by a cross-coupling reaction. The electronic and photophysical properties of the novel BN-tetraphene system were investigated using UV-vis and fluorescence spectroscopy, electrochemical cyclic voltammetry, and DFT calculations, which disclosed its distinct electronic and photophysical properties from the analogous hydrocarbon system.