Regioselective C8-metalation of N-phosphine tethered adenine derivatives via C8-H activation.

Two new adenine derivatives bearing a N-methylene (1) or N-ethylene (2) tethered diphenylphosphine group have been reacted with [MIIICl2Cp*]2 (M = Ir, Rh) or [RuIIClCp*]4. The formation of Werner-type phosphine complexes [3]-[6] and upon heating their subsequent rearrangement into complexes bearing an NH,NR-NHC^PRPh2 chelate ligand in [7]Cl (M = Ir) and [8] (M = Ru) have been observed.