Chromyl(V) complexes of eleven different meso-aryl- and [Formula: see text]-alkylcorrole ligands have been prepared and characterized by analytical, spectroscopical, electrochemical and structural means. All seven new complexes show the expected optical spectra of chromyl(V) corroles with the Soret band situated slightly above (meso-arylcorroles) or below ([Formula: see text]-alkylcorrole) 400 nm, and with an isotropic room temperature EPR signal for the [Formula: see text] ion Cr(V) at about [Formula: see text]. Cyclic voltammetry evidences two or three quasi-reversible one-electron redox steps, which are characterized as two ligand-centered processes and one metal-centered process based on spectroelectrochemical measurements and a Hammett analysis. Chemical reduction to a chromyl(IV) corrolate was successfully performed using NaHg and NEt3. Citric acid, however, produces a different reduction product, for which an isocorrole structure is proposed. Six chromyl(V) corroles could be analysed by seven single crystal diffraction analyses. The obtained molecular data prove the presence of remarkably similar CrN4O coordination units independent of the corrole substitution pattern, and of macrocyclic conformations which can be understood as comprised mainly of a doming mode, a more or less pronounced saddling mode, and one out of two different and dominating ruffling modes.

Seit den 1. Oktober 2021 ist sie verbindlich umzusetzen: die Einstufung von Titandioxid‐Pulvern in der CLP‐Verordnung als Krebsverdachtsstoff (Karzinogen, Kategorie 2). Der Einstufungseintrag ist komplex und stellt sowohl Hersteller als auch Verarbeiter von Titandioxid vor neue Herausforderungen.

Cationic nickel(II), palladium(II), and copper(II) isocorrole complexes were obtained from linear tetrapyrrolic 2,2′bidipyrrin precursors by metal-templated oxidative macrocyclization reactions using silver(I) tetrafluoroborate as the oxidant in 40-69 % yield. The new compounds were characterized by optical and resonance methods. Two products from overoxidation and attack of nucleophiles were identified by means of single-crystal X-ray diffraction, elucidating possible H atom [a] .62, triclinic, space group P1 , a = 11.4751 (2) Å, b = 12.2697(2) Å, c = 15.8838(3) Å, α = 96.196(2)°, = 102.527(2)°, γ = 116.272(2)°, V = 1903.75(7) Å 3 , Z = 2, ρ calc = 1.255 g cm -3 , μ(Cu-K α ) = 1.011 mm -1 , R 1 [I > 2σ(I)] = 0.0479, wR 2 (all data) = 0.1408. Crystal Data for 15: C 46 H 52 CuN 4 , M = 724.45, triclinic, space group P1 , a = 11.1150(5) Å, b = 12.3637(7) Å, c = 16.2701(6) Å, α = 96.602(4)°, = 102.207(3)°, γ = 115.355(5)°, V = 1920.6(2) Å 3 , Z = 2, ρ calc = 1.253 g cm -3 , μ(Cu-K α ) = 1.076 mm -1 , R 1 [I > 2σ(I)] = 0.0563, wR 2 (all data) = 0.1615. Crystal Data for 30: C 92 H 100 F 12 N 8 Ni 2 Sb 2 + 3.566×(CH 2 Cl 2 ) M = 2209.55, triclinic, space group P1, a = 17.4048(8) Å, b = 17.5535(8) Å, c = 19.7399(8) Å, α = 84.942(4)°, = 68.619(4)°, γ = 60.298(4)°, V = 4846.0(4) Å 3 , Z = 2, ρ calc = 1.510 g cm -3 , μ(Cu-K α ) = 7.190 mm -1 , R 1 [I > 2σ(I)] = 0.0628, wR 2 (all data) = 0.1701. Crystal Data for 31: C 38 H 50 N 4 NiO 2 , M = 653.53, monoclinic, space group P2 1 /c, a = 13.3144(3) Å, b = 17.0511(5) Å, c = 15.0318(3) Å, = 100.396(2)°, V = 3356.58(14) Å 3 , Z = 4, ρ calc = 1.293 g cm -3 , μ(Cu-K α ) = 1.133 mm -1 , R 1 [I > 2σ(I)] = 0.0395, wR 2 (all data) = 0.1090. CCDC 1938499 (for 13), 1938498 (for 15), 1056473 (for 30), and 1938500 (for 31) contain the supplementary crystallographic data for this paper. These data can be obtained free of charge from The Cambridge Crystallographic Data Centre.

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