Abstract: In order to study the effects of the substituted groups on the properties of the complexes, a series of rhenium(Ⅰ)₂,2′-bipyridyl complexes [fac-(4,4′-di-COOEt-bpy)Re(CO)₃(X—pyridine)PF₆], where bpy is 2,2′-bipyridine and X is 4-methyl, 3-hydroxy, 4-hydroxy, 4-amino, or H, were synthesized with a yield more than 90%, and characterized by ¹H NMR, ¹³C NMR, 2D-NMR( ¹H-¹H COSY, HMBC, HSQC), ESI-MS and HRMS. The δ H values on the X—pyridine ring were shifted to up-field in ¹H NMR and the MLCT absorbance maxima were red-shifted asthe X groups became more electron-donating from H to 4-methyl, 4-hydroxy or 4-amino. The ESI-MS and HRMS showed the mono-charged peaks and their isotopic peaks of the complexes. The absorption maximum of 1d(X= 4-amino) is 20 nm longer than that of 1e(X=H). It might be used to broaden the absorption range of solar cells.

Key words: Rhenium(Ⅰ) bipyridyl complex, Photosensitive dyes, Nanocrystalline photovoltaic cells