DOI: 10.1002/chem.201501979
Cover Profile
Group 9 Metal Complexes of meso-Aryl-Substituted Rubyrin
Takanori Soya
Atsuhiro Osuka
Invited for the cover of this issue are Takanori Soya and Atsuhiro Osuka at Kyoto University. The image depicts Group 9 metal (Co, Rh, and Ir) complexes of meso-aryl-substituted rubyrin and a meteorite approaching to the atmosphere. A large amount of Iridium is often contained in meteorites. Read the full text of the article at 10.1002/chem.201501080.
What is the most significant result of this study? Rubyrins are hexaphyrin variants that lack two meso-carbons from regular hexaphyrins(1.1.1.1.1.1) and can be delineated as hexaphyrins(1.1.0.1.1.0). While rubyrins are attractive molecules in light of their planar structures and aromaticity, metalation of rubyrins has been scarcely explored, which contrasts to the metalation chemistry of regular hexaphyrins. This work has revealed the metalation chemistry of meso-tetrakis(pentafluorophenyl) rubyrin with Group 9 metals such as CoII, RhI, and IrIII. Synthesized complexes are a Hìckel aromatic bis-RhI complex of [26]rubyrin with a highly curved gable-like structure, and a Hìckel antiaromatic bis-CoII complex of [24]rubyrin that displays intramolecular antiferromagnetic coupling between the two CoII ions, and two Cp*-capped IrIII complexes, one of which shows the IrIII on the [26]rubyrin frame with two Ir¢N bonds and the other complex displays a Ir¢C bond as a rare case of Ir complexes of porphyrinoids.
[50]dodecaphyrin(1.1.0.1.1.0.1.1.0.1.1.0) (see, Chem. Eur. J. 2014, 21, 8341). We hope to break this record soon by exploring larger aromatic molecules and to confirm switching of aromaticity upon two-electron redox processes.
Is your current research mainly curiosity driven (fundamental) or rather applied? The present research is definitely curiosity driven. Unexpectedly, metalation of [26]rubyrin with Co(OAc)2·4 H2O produced a bis-CoII complex of [24]rubyrin, indicating a non-innocent nature of the [26]rubyrin. This complex has conjugated 24p electrons and a roughly planar conformation and is hence a stable antiaromatic molecule, which has been supported by its UV/vis absorption spectral features and a small HOMO–LUMO gap.
What other topics are you working on at the moment? Besides our research on the exploration of novel metal complexes of expanded porphyrins, we are also active in exploring gigantic aromatic/antiaromatic molecules using large expanded porphyrins. Aromaticity/antiaromaticity depends on the number of conjugated p-electrons and topology of the macrocycle (either Hìckel or Mçbius). At the moment, the largest Hìckel aromatic molecule is
Chem. Eur. J. 2015, 21, 10585
10585
Ó 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Cover Profile
Group 9 Metal Complexes of meso-Aryl-Substituted Rubyrin
Takanori Soya
Atsuhiro Osuka
Invited for the cover of this issue are Takanori Soya and Atsuhiro Osuka at Kyoto University. The image depicts Group 9 metal (Co, Rh, and Ir) complexes of meso-aryl-substituted rubyrin and a meteorite approaching to the atmosphere. A large amount of Iridium is often contained in meteorites. Read the full text of the article at 10.1002/chem.201501080.
What is the most significant result of this study? Rubyrins are hexaphyrin variants that lack two meso-carbons from regular hexaphyrins(1.1.1.1.1.1) and can be delineated as hexaphyrins(1.1.0.1.1.0). While rubyrins are attractive molecules in light of their planar structures and aromaticity, metalation of rubyrins has been scarcely explored, which contrasts to the metalation chemistry of regular hexaphyrins. This work has revealed the metalation chemistry of meso-tetrakis(pentafluorophenyl) rubyrin with Group 9 metals such as CoII, RhI, and IrIII. Synthesized complexes are a Hìckel aromatic bis-RhI complex of [26]rubyrin with a highly curved gable-like structure, and a Hìckel antiaromatic bis-CoII complex of [24]rubyrin that displays intramolecular antiferromagnetic coupling between the two CoII ions, and two Cp*-capped IrIII complexes, one of which shows the IrIII on the [26]rubyrin frame with two Ir¢N bonds and the other complex displays a Ir¢C bond as a rare case of Ir complexes of porphyrinoids.
[50]dodecaphyrin(1.1.0.1.1.0.1.1.0.1.1.0) (see, Chem. Eur. J. 2014, 21, 8341). We hope to break this record soon by exploring larger aromatic molecules and to confirm switching of aromaticity upon two-electron redox processes.
Is your current research mainly curiosity driven (fundamental) or rather applied? The present research is definitely curiosity driven. Unexpectedly, metalation of [26]rubyrin with Co(OAc)2·4 H2O produced a bis-CoII complex of [24]rubyrin, indicating a non-innocent nature of the [26]rubyrin. This complex has conjugated 24p electrons and a roughly planar conformation and is hence a stable antiaromatic molecule, which has been supported by its UV/vis absorption spectral features and a small HOMO–LUMO gap.
What other topics are you working on at the moment? Besides our research on the exploration of novel metal complexes of expanded porphyrins, we are also active in exploring gigantic aromatic/antiaromatic molecules using large expanded porphyrins. Aromaticity/antiaromaticity depends on the number of conjugated p-electrons and topology of the macrocycle (either Hìckel or Mçbius). At the moment, the largest Hìckel aromatic molecule is
Chem. Eur. J. 2015, 21, 10585
10585
Ó 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
