Are there any stable complexes where an (N-unsubstituted) imine is bound eta^2 to a (late) transition metal?

I've been looking for an example of a stable complex where a $\ce{C=N}$ is coordinated $\eta^2$ to a (late) transition metal, but could not find any. Do they exist at all? 


For $\ce{C=C}$ there are countless examples, Zeiss' salt, $\ce{Ni(COD)\_2}$, etc.


If no or only very few $\ce{C=N}$ analogs exist, what's the reason?


