Breaking the strongest bonds

A compound that can break the strongest known chemical bonds ― those in the molecules of nitrogen and carbon monoxide ― and put the different atoms back together to form a useful compound is reported in Nature Chemistry this week. Being able to make use of these simple and abundantly available gases could reduce our dependence on fossil fuels for the preparation of many important chemicals.

Paul Chirik and colleagues created a complex based on the metal hafnium that uses carbon monoxide to break the nitrogen-nitrogen bond, and at the same time make new carbon-carbon and carbon-nitrogen bonds. Adding some hydrogen, in the form of a weak acid, creates oxamide ― an important agrochemical that is currently made from fossil fuels.

The whole process operates at ambient temperature, which is remarkable given the stability of nitrogen ― 78% of the Earth's atmosphere. The reactivity of carbon monoxide is even more unexpected, as it is known to form very stable compounds with many metals.