Nitrate NO more

Now, the group has found that the triflate salt of these complexes, N(afa^Cy)₃FeOTf₂, is effective for transient coordination of nitrate and perchlorate to the metal, forming intermediates that readily react to form the desired iron nitrosyl and chloride complexes. Comparison to the redox-inert zinc analogues showed that the secondary coordination sphere was not involved in coordinating the oxyanions. It was, however, required for reduction, playing a significant role in stabilizing the metal–oxo centre. The team then demonstrated catalytic reductions, resulting in 3.5 turnovers for nitrate and 3 turnovers for perchlorate — while low, even a few turnovers for such challenging reactions is impressive. Although there is work to come in developing a more practical reduction process, these results show that well-designed small-molecule catalysts can handle even the toughest of redox reactions.