Oxidative chemical vapour deposition of (5,15‐diphenylporphyrinato)nickel(II) (NiDPP) with iron(III) chloride as oxidant yielded a conjugated poly(metalloporphyrin) as a highly coloured thin film, which is potentially useful for optoelectronic applications. This study clarified the reactive sites of the porphyrin monomer NiDPP by HRMS, UV/Vis/NIR spectroscopy, cyclic voltammetry and EPR spectroscopy in combination with quantum chemical calculations. Unsubstituted meso positions are essential for successful polymerisation, as demonstrated by varying the porphyrin meso substituent pattern from di‐ to tri‐ and tetraphenyl substitution. DFT calculations support the proposed radical oxidative coupling mechanism and explain the regioselectivity of the C−C coupling processes. Depositing the conjugated polymer on glass slides and on thermoplastic transparent polyethylene naphthalate demonstrated the suitability of the porphyrin material for flexible optoelectronic devices.

Reversing the metal-to-ligand charge transfer ( 3 MLCT)/metal-centered ( 3 MC) excited state order in iron(II) complexes is ac hallengingo bjective, yet would finally result in long-sought luminescent transition-metal complexes with an earth-abundant central ion. One approacht oa chieve this goal is based on low-energy charge-transfer absorptions in combination with as trong ligand field. Coordinating electron-rich and electron-poor tridentate oligopyridine ligands with large bite angles at iron(II) enables both low-energy MLCT absorption bands around 590 nm and as trong ligand field. Variations of the electron-rich ligand by introducing longer alkyl substituents destabilizes the iron(II) complex towards ligand substitution reactions while hardly affecting the optical properties. On the other hand, N-deprotonation of the ligand backbone is feasible andr eversible, yielding deep-green complexes with charge-transfer bands extending into the near-IRr egion.T ime-dependent density functional theory calculations assign these absorption bands to transitions with dipole-allowed ligand-to-ligand charget ransfer character.T his unique geometric and electronic situation establishes af urtherr egulating screw to increase the energy gap betweenp otentially emitting charge-transfer states and the non-radiativeligand field states of iron(II) dyes.

The bimetallic copper(I) complex CuL (cis-1) is formed with high diasteroselectivity from [Cu(NCCH)][BF] and HL (4-tert-butyl phenyl(pyrrolato-2-yl-methylene)amine) in a kinetically controlled reaction. cis-1 features a rather short Cu···Cu distance of 2.4756(6) Å and is weakly emissive at room temperature in solution. Oxidatively triggered disproportionation of cis-1 yields elemental copper and the mononuclear copper(II) complex CuL (trans-2). One-electron reduction of trans-2 gives cuprate [2] with a bent bis(pyrrolato) coordinated copper(I) entity. The imine donor atoms of [2] can insert an additional copper(I) ion giving exclusively the bimetallic complex cis-1 closing the oxidation-elimination-reduction-insertion cycle.

CuII and AuIII chlorido complexes bearing the bis(NHC) carbazolide pincer ligand (bimca) were synthesized by transmetallation from the respective lithium complex [Li(bimca)] (NHC=N-heterocyclic carbene). In the case of copper, two different molecular structures were obtained depending on the copper source. With Cu(II) chloride the paramagnetic mononuclear [Cu(bimca)Cl] complex is formed and has been characterized by EPR spectroscopy and X-ray structure analysis, while copper(I) chloride leads under oxidation to a dinuclear structure in which two cationic [CuII(bimca)] moieties are bridged by one chlorido ligand. The positive charge is compensated by the [CuCl2]− counter ion, as proven by X-ray structure analysis. Transmetallation of [Li(bimca)] with AuCl3 leads to the [Au(bimca)Cl]+ complex with a tetrachloridoaurate counter ion.

2‐Iminopyrroles [HtBuL, 4‐tert‐butyl phenyl(pyrrol‐2‐ylmethylene)amine] are non‐fluorescent π systems. However, they display blue fluorescence after deprotonation with alkali metal bases in the solid state and in solution at room temperature. In the solid state, the alkali metal 2‐imino pyrrolates, M(tBuL), aggregate to dimers, [M(tBuL)(NCR)]2 (M=Li, R=CH3, CH(CH3)CNH2), or polymers, [M(tBuL)]n (M=Na, K). In solution (solv=CH3CN, DMSO, THF, and toluene), solvated, uncharged monomeric species M(tBuL)(solv)m with N,N′‐chelated alkali metal ions are present. Due to the electron‐rich pyrrolate and the electron‐poor arylimino moiety, the M(tBuL) chromophore possesses a low‐energy intraligand charge‐transfer (ILCT) excited state. The chelated alkali cations rigidify the chromophore, restricting intramolecular motions (RIM) by the chelation‐enhanced fluorescence (CHEF) effect in solution and, consequently, switch‐on a blue fluorescence emission.