TM-Polyene Complexes

Question 1

Polyenes

Answer 1

Ligands with extended π-systems

Question 2

Electronic structure

Answer 2

Each C contributes one p orbital and one electron to π-system, energies of π-MOs formed different according to number of nodes between Cs in the chain

Question 3

Bonding in TM-linear polyene complexes

Answer 3

Synergic bonding with e- donation from occupied ligand π-MOs reinforced by back bonding from MC to vacant ligand π-MOs

Question 4

Electronic structure cyclic polyene ligands

Answer 4

Energy of π-MOs increases with number of nodes, cyclic polyene have degeneracy, pattern from Frost diagram