Synthesis and Characterisation of Transition Metal Complexes of a Novel 1,5‐benzodiazepine‐Functionalised Tertiary Phosphine

The one-step synthesis (44 % isolated yield) of the 1,5-benzodiazapine functionalised phosphine 1, C31H31N2OP, is reported. Bridge cleavage {MCl(μ-Cl)(η5-Cp*)}2 (M=Ir, Rh) with 2 equiv. 1 in CH2Cl2 gave mononuclear compounds [MCl2(η5-Cp*)(P-1)] a; M=Rh, b) which functions as a P-monodentate ligand. Rapid C(sp3)−H bond activation, at room temperature, observed for leading to unusual cyclometallated complex [Ir(η5-Cp*)(P,N,C-1)]Cl2 3 (or 3‘) bearing an anionic P/Namine/C-terdentate Reaction [Pt(CH3)Cl(η4-cod)] one led [Pt(CH3)Cl(P,N-1)] 4, suggesting that may form via intermediate IrIII cationic species ligand P,N-bound. IrI [IrCl(η4-cod)(P-1)] 5 does not, under similar conditions, show any evidence C−H activation. Single crystal X-ray studies on a, b, 3, 3‘, and reveal intramolecular N ⋅⋅⋅ H−O H-bonding all cases.