Phenanthroline-polyoxometalate hybrid compounds and the observation of intramolecular charge transfer.
A phenanthroline ligand has been covalently modified at the 2 and 9 positions by an aminophenylhexamolybdate substituent. The 1H NMR spectrum indicated a strong electron-withdrawing effect of the hexamolybdate (Mo6O19(2-)) moiety on the phenanthroline ligand. UV-vis and cyclic voltammetry showed extended conjugation of the hybrid phenanthroline-polyoxometalate compound and the possibility of easy oxidation of the extended phenanathroline ligand. Further EPR experiments provided strong evidence for an intramolecular charge-transfer process with the formation of a phenanthroline cation radical and a reduced hexamolybdate.
Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, Israel 76100.
Itsik
I
Bar-Nahum
K V
KV
Narasimhulu
Lev
L
Weiner
Ronny
R
Neumann