Synthesis and optical properties of subphthalocyanine homo- and heterodimers axially connected via a hydroquinone linker.

Axially linked trifluoroethoxy (TFEO)-coated subphthalocyanine (SubPc) homo- and heterodimers were synthesized by two different axial ligand substitution methods. TFEO-SubPc homodimers were obtained directly from TFEO-SubPc boron chloride with o-, m-, and p-hydroquinones, while TFEO-SubPc heterodimers were synthesized via stepwise construction using a combination of the TFEO method and Torres' triflate method. The optical properties of the dimers obtained were investigated using UV-Vis and fluorescence spectrometry. Electron transfer was observed in the heterodimers, and TFEO-SubPc acted as an electron acceptor in the process. The electron transfer process differs depending on the o-, m-, and p-geometries of the hydroquinone linker, and is supported by computational calculations.