N-H versus C-H activation of a pyrrole imine at {Cp*Ir}: A computational and experimental study

Reaction of a pyrrole imine with [IrCl2Cp*](2)/NaOAc leads to N- H activation in preference to C-H activation at the pyrrole; howeVer, with the N- methylated ligand C- H activation occurs. Density functional calculations show that N- H bond activation is both kinetically and thermodynamically preferred to C- H activation. Both reactions occur with relatively low energy barriers by an electrophilic agostic interaction with the metal with simultaneous intramolecular hydrogen bonding with acetate leading to deprotonation Via a six- membered transition state.