-Chapter 1: Introduction to Tripodal N-Heterocyclic Carbene Iron Complexes.- Chapter 2: TIMENmes - An Iron Nitride Complex. -Chapter 3: TIMENtol/3,5xyl Unexpected Reactivity Resulting from Modifications of the\nLigand Periphery. -Chapter 4: TIMEN3,5CF3 Hybrid System Capable of Cyclometallation and Nitride\nInsertion. -Chapter 5: PhB(tBuIm)3 Synthesis, Structure, and Reactivity of an Iron(V) Nitride. -Chapter 6: PhB(MesIm)3 Spin Crossover in a Four-Coordinate Iron(II) Complex.