Syntheses, structural characterisation and electronic structures of some simple acyclic amino carbene complexes.

Reactions of the vinylidene complexes [M([double bond, length as m-dash]C[double bond, length as m-dash]CH2)(PP)Cp']PF6 with NH3 readily afford the acyclic amino carbene complexes [M{C(Me)NH2}(PP)Cp']PF6 [M(PP)Cp' = Fe(dppe)Cp, Ru(dppe)Cp, Ru(PPh3)2Cp, Ru(dppe)Cp*]. Crystallographic, spectroscopic and computational data support a description of these complexes in terms of a M-{C(Me)[double bond, length as m-dash]N(+)H2} mesomeric form, and simple σ-coordination of the singlet acyclic amino carbene.