Nitrogen fixation: Part I. Electrochemical reduction of titanium compounds in the presence of catechol and N2 in MeOH or THF

The cyclic voltammetry of Cp₂TiCl₂ was studied in both MeOH and THF, at either glassy carbon or platinum electrodes. The effect of catechol added, as a complexation agent, on the shape of the voltammograms is also described. Controlled potential electrolysis (CPE) was employed to reduce CP₂TiCl₂ under an N₂ atmosphere in the presence of catechol. Ammonia was formed in low chemical yields (up to 0.11%), but selectively. The reduction was also investigated in the presence of a base (MeONa) and divalent cation (Mg²⁺). The ammonia yield increased to 0.65% and 1.45%, respectively. Other titanium compounds ((acac)₂TiCl₂, (i-PrO)₄Ti, TiCl₄, TiCl₃) were reduced under similar conditions and found to be less efficient for N₂ reduction than Cp₂TiCl₂.