Why have one type of metal-nitrogen bond when you can have three? Well, a team from Michigan State University have done just that! A fascinating nitrogen analogue of the Schrock and Clark “yl-ene-yne” complex, W(CBut)(CHBut)(CH2But)(dmpe), has been published in Chemical Science today.
The compound and Schrock’s carbon analogue were both analysed using a combination of Mayer bond orders and Natural Resonance Theory (see above), which were both in good agreement and showed triple, double and single bonds to all be present in each compound.
The new compound unsurprisingly gave interesting reaction products with different electrophiles. Indeed, reactions with methyl iodide and acetic anhydride occur at the imido nitrogen, which may be predictable since you might expect a more negative charge to be located there. However, pivaloyl chloride reacts at the nitrido nitrogen atom, giving a rare example of a transition metal nitrido complex containing a carboxyl group on the nitrogen. This outcome may be down to sterics, but it would be very interesting to see the scope of reactivity with this new complex and other electrophiles.
All in all, this is a pretty cool new compound, and I’m sure we’ll see lots of interesting chemistry coming from it.