A new class of tethered-arene ruthenium(II) complexes with pendant P and C donor atoms: synthesis of eta6:eta1:eta1 phosphonio-azabutadienyl ruthenabicycles via allenylidene intermediates.

The activation of 1,1-diphenyl-2-propyn-1-ol by complexes [RuCl(eta(6)-p-cymene)[eta(2)-P,N-Ph(2)PCH(2)P([=NR)Ph(2)]](+) results in the formation of the unusual tethered (eta(6)-arene)-ruthenium(ii) derivatives, via an unprecedented iminophosphorane-allenylidene coupling process.