Geometric and electronic structures of boron(III)-cored dyes tailored by incorporation of heteroatoms into ligands.

Complexation of a boron atom with a series of bidentate heterocyclic ligands successfully gives rise to corresponding BF2-chelated heteroarenes, which could be considered as novel boron(III)-cored dyes. These dye molecules exhibit planar structures and expanded p-conjugated backbones due to the locked conformation with a boron center. The geometric and electronic structures of these BF2 complexes can be tailored by embedding heteroatoms in the unique modes to form positional isomer and isoelectronic structures. The structure-property relationship is further elucidated by studying the photophysical properties, electrochemical behavior and quantum-chemical calculations.