Synthesis, Characterization, and Electronic Properties of Porphyrins Conjugated with N-Heterocyclic Carbene (NHC)–Gold(I) Complexes

Abstract

International audiencePorphyrins fused to peripheral N-heterocyclic carbenes (NHC) across two neighboring β,β-pyrrolic positions were used for the synthesis of different mono- and bis-carbenic gold(I) complexes. These studies also revealed how it is possible to modulate the reactivity of the peripheral NHC by deprotonating the inner NH groups of the fused free base porphyrin core. All complexes were fully characterized and displayed high stability, allowing the formation of mono-carbenic and also stable homoleptic and heteroleptic bis-carbenic Au(I) complexes. Optical and electrochemical properties of bis-carbenic Au(I) revealed no or weak electronic communication between the porphyrins, which behave as two independent groups

Porphyrins Conjugated with Peripheral Thiolato Gold(I) Complexes for Enhanced Photodynamic Therapy

“…We have previously shown that Ni‐porphyrin fused to imidazolium salt Ni‐I could be used as NHC precursor for the synthesis of the monocarbenic Au I complex [NiAuCl] . First, the NHC‐Ag I complex was obtained by reacting Ni‐I with Ag 2 O.…”

Gadolinium(III) Porpholactones as Efficient and Robust Singlet Oxygen Photosensitizers

“…The determined turnover numbers( TONs)i ncreased from 68-84( Gd-1-2)t o1 12 and 108 for Gd-3 and Gd-4,r espectively,h ighert han the previously reported results for metalloporphyrins. [35] These results indicated that lactonization may be an ew access route to improve the reactivity of Gd porphyrinates in photoredox catalysis for their highers inglet oxygen sensitization ability.…”

Molecular complexes and main-chain organometallic polymers based on Janus bis(carbenes) fused to metalloporphyrins

“…We have previously shown that porphyrins fused to imidazolium rings could be used as NHC precurors to anchor different metal ions such as palladium, 34,35 rhodium, 36 silver 37 and gold 38,39 at their periphery. Recently, we reported the synthesis of porphyrins containing two imidazolium rings fused to two opposite pyrrole units.…”