Synthesis and Isotope Effects on the Excited State Properties of N^N Bound [Ir(polypyridyl)2Cl2]PF6 Complexes

Abstract

A versatile approach to the preparation of [Ir(LL)2Cl2](PF6) type complexes is reported, in which LL is an N^N bound polypyridyl ligand [X2bpy, X2phen, where X = H-, CH3-, (CH3)3C-, or phenyl-, and bpy = 2,2′-bipyridyl, phen = 1,10- phenanthroline] as well as their deuterated analogues. In the synthesis of [Ir(bpy)2Cl2]PF6 (I) and its deuterated analogue (III), the cyclometallated complexes [Ir(bpy)2(bpy-C–N)](PF6)2 (II) and [Ir([D8]-bpy)2([D8]-bpy-C–N)](PF6)2 (IV) were also obtained. The complexes are characterised by 1H NMR, UV/Vis absorption and emission spectroscopy. The effect of deuteration on emission quantum yields and emission lifetimes is discussed. The ready availability of these complexes through efficient scaleable synthetics routes opens new opportunities for their use, especially in energy related applications.