Pentacoordinated Cobalt(II) and Manganese(II) porphyrin N-Heterocyclic carbenes: Isolation, characterization and spectroscopy

Abstract In this work, the first example of isolation and determinations of the cobalt (II) tetraphenylporyphyrin carbene [Co(TPP) (1,3-Me2Imd)] and a new Mn(II) analogue [Mn (TPP) (1,3-Me2Imd)] have been reported. Spectroscopic studies and comparisons with related analogues have determined low spin S = 1/2 state of the Co(II) complex and given deep insights into the behaviors of NHCs as axial ligands of metalloporphyrins. The work would push forward the research and application of these species as dyes and sensitizers.