The reaction of tetrathiafulvalene (TTF) or benzidine (Bz) with gels of V 2O 5 has been studied and some physicochemical characteristics of the two molecular bronzes thus obtained are given and compared. The reaction of TTF with V 2O 5 results in a charge transfer which shows up in the EPR, XPS and IR spectra. Up to a TTF/V 2O 5 molar ratio, x, of the order of35, the redox chemical reaction induces an amorphization of the solid. Beyond this value, a new crystalline phase is formed. The conductivity is both ionic, involving the diffusion of protons, and electronic, involving the O-V lattice. The electronic component, which involves the mixed valence character of the oxide, is strongly x-dependent, with a sharp maximum around x=0.17. The Bz-V 2O 5 gel is quite different. The reaction is a true intercalation reaction, with a maximum stoichiometry corresponding to x=1. The crystalline order of the layered solid is improved upon intercalation owing to the formation of hydrogen bonds between Bz and the host lattice. In the intercalation compound, Bz is cationic, but the electrons injected in the oxide lattice are delocalized and do not participate in the hopping mechanism of electronic conduction.