A triarylborane-based biphenyl exhibiting abrupt fluorescence enhancement at a specific high temperature.

A triarylborane-based biphenyl, 4,4'-dibromo-2-dimesitylboryl-2'-(N,N-dimethylamino)biphenyl (Br2-BN-BPh), exhibits very unique temperature-dependent fluorescence behavior. Although Br2-BN-BPh is weakly emissive at room temperature, its fluorescence increases abruptly at a specific high temperature (68 °C in MOE, 88 °C in toluene). In addition, the fluorescence still remains very strong even after cooling to room temperature, providing the possibility of the fluorescence detection of a specific high temperature.