Synthesis and structure of Fe(TIM)(CNBPh3)2: TIM = 2,3,9,10-tetramethyl-1,4,8,11-tetraazacyclotetradeca-1,3,8,10-tetraene. Conversion of BPh4- into CNBPh3-

The reaction of a solution of FeCl2 in methanol, TIM, and acetic acid with NaCN and then with NaBPh4 gives trans-Fe(TIM)(CNBPh3)2, (TIM = 2,3,9,10tetramethyl-1,4,8,11-tetracyclotetradeca-1,3,8,10-tetraene). The complex has an octahedral geometry with equatorial-TIM-ligand and axial-CNBPh3 ligands. The reaction mechanism involves abstraction of a phenyl anion from BPh4-. The resulting BPh3 reacts with the biscyano-Fe complex, which is electron rich and acts as a lewis base. The sensitivity of organometallic compounds to acid poses a limitation to the process.