Facile [N]C−H Activation by a ( P , N )‐Chelate [3]Ferrocenophane−Ruthenium System

The chelate ligand 5 was prepared from the corresponding (dimethylamino)[3]ferrocenophane by directed ortho ‐lithiation with n ‐butyllithium followed by treatment with ClPPh 2 . The rigid ( P , N )‐chelate ligand reacts with [Ru(η 6 ‐ p ‐cymene)Cl 2 ] dimer in the presence of KPF 6 in methanol to afford two products in an almost equimolar ratio. Instead of the simple addition product of the [Ru( p ‐cymene)Cl] + cation reagent to the chelate, selective C−H abstraction at an N−CH 3 moiety occurs with the formation of the “metallaaziridinium”‐type product 8 (isolated as its PF 6 − salt). The liberated equivalent of HCl is trapped by the putative ( P , N )‐chelate [RuCl] + complex intermediate to form the corresponding internal hydrochloride complex 7 . The starting material 5 and the products 8 and 7 were characterised by single‐crystal X‐ray diffraction studies. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)