Jump to Main Content
Switchable Aromaticity in an Isostructural Mn Phthalocyanine Series Isolated in Five Separate Redox States
- Hunt, Camden, Peterson, Madeline, Anderson, Cassidy, Chang, Tieyan, Wu, Guang, Scheiner, Steve, Ménard, Gabriel
- Journal of the American Chemical Society 2019 v.141 no.6 pp. 2604-2613
- manganese, models, oxidation, spectroscopy
- The synthesis and characterization of a new phthalocyanine (Pc) Mn-nitride complex, (ᴼᴱᵗPc)MnN (2; ᴼᴱᵗPc = 1,4,8,11,15,18,22,25-octaethoxy-Pc), as well as its stable, readily accessible oxidized (2⁺ and 2²⁺) and reduced (2–, 2²–) congeners is reported. This unique isostructural series displays switchable aromatic character spanning the aromatic (2), nonaromatic (2²⁺), and antiaromatic (2²–) triad, in addition to the open-shell radical states (2⁺, 2–). All complexes were structurally characterized and displayed significant structural distortions at the redox extrema (2²⁺, 2²–) consistent with proposed [16 or 18]annulene π ring circuit models. Spectroscopic and computational studies further support these models. This isolated, fully characterized, isostructural series spanning five redox states (2²⁺, 2⁺, 2, 2–, 2²–) is unique in both the Pc and related macrocyclic (ex. porphyrinoids) literature and may offer direct insight into structural–electronic correlations driven by switchable aromaticity.