Tris(trifluoromethyl)germylethynyl derivatives of biphenyl and anthracene: Synthesis, structure, and evidence of the intramolecular charge transfer on the germanium center

Symmetrical and unsymmetrical 4,4′-biphenyl, and 9,10-anthracene derivatives with tris(trifluoromethyl)germylethynyl –CC–Ge(CF3)3 substitutes have been prepared, their properties have been studied and compared with those of dimethyl(phenyl)silylethynyl –CC–Si(Ph)Me2 compounds. UV–visible absorption, steady-state, and time-resolved fluorescence spectra in solution for this germanium and silicon compounds have been investigated. The process of photoinduced electron-transfer from the aromatic group to the germanium center has been found in the unsymmetrical 4-biphenyl –CC–Ge(CF3)3 molecule. Anthracene derivatives with –CC–Ge(CF3)3 substitutes have been characterized crystallographically.