skip to main content

DOE PAGESDOE PAGES

Title: Cobalt- and Rhodium-Corrole-Triphenylphosphine Complexes Revisited: The Question of a Noninnocent Corrole

Here, a reinvestigation of cobalt-corrole-triphenylphosphine complexes has yielded an unexpectedly subtle picture of their electronic structures. UV-vis absorption spectroscopy, skeletal bond length alternations observed in X-ray structures, and broken-symmetry DFT (B3LYP) calculations suggest partial Co II-corrole •2– character for these complexes. The same methods applied to the analogous rhodium corroles evince no evidence of a noninnocent corrole. X-ray absorption spectroscopic studies showed that the Co K rising edge of Co[TPC](PPh 3) (TPC = triphenylcorrole) is redshifted by ~1.8 eV relative to the bona fide Co(III) complexes Co[TPC](py) 2 and Co[TPP](py)Cl (TPP = tetraphenylporphyrin, py = pyridine), consistent with a partial Co II-corrole •2– description for Co[TPC](PPh 3). Electrochemical measurements have shown that both the Co and Rh complexes undergo two reversible oxidations and 1-2 irreversible reductions. In particular, the first reduction of the Rh corroles occurs at significantly more negative potentials than that of the Co corroles, reflecting significantly higher stability of the Rh(III) state relative to Co(III). Together, the results presented herein suggest that cobalt-corrole-triphenylphosphine complexes are significantly noninnocent with moderate Co II-corrole •2– character, underscoring – yet again – the ubiquity of ligand noninnocence among first-row transition metal corroles.
Authors:
 [1] ;  [1] ;  [2] ;  [3] ; ORCiD logo [3] ;  [4] ;  [2] ; ORCiD logo [1]
  1. UiT - The Arctic Univ. of Norway, Tromso (Norway)
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States)
  3. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
  4. Univ. of the Free State, Bloemfontein (Republic of South Africa)
Publication Date:
Grant/Contract Number:
AC02-76SF00515
Type:
Accepted Manuscript
Journal Name:
Inorganic Chemistry
Additional Journal Information:
Journal Volume: 56; Journal Issue: 24; Journal ID: ISSN 0020-1669
Publisher:
American Chemical Society (ACS)
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
OSTI Identifier:
1462208

Ganguly, Sumit, Renz, Diemo, Giles, Logan J., Gagnon, Kevin J., McCormick, Laura J., Conradie, Jeanet, Sarangi, Ritimukta, and Ghosh, Abhik. Cobalt- and Rhodium-Corrole-Triphenylphosphine Complexes Revisited: The Question of a Noninnocent Corrole. United States: N. p., Web. doi:10.1021/acs.inorgchem.7b01828.
Ganguly, Sumit, Renz, Diemo, Giles, Logan J., Gagnon, Kevin J., McCormick, Laura J., Conradie, Jeanet, Sarangi, Ritimukta, & Ghosh, Abhik. Cobalt- and Rhodium-Corrole-Triphenylphosphine Complexes Revisited: The Question of a Noninnocent Corrole. United States. doi:10.1021/acs.inorgchem.7b01828.
Ganguly, Sumit, Renz, Diemo, Giles, Logan J., Gagnon, Kevin J., McCormick, Laura J., Conradie, Jeanet, Sarangi, Ritimukta, and Ghosh, Abhik. 2017. "Cobalt- and Rhodium-Corrole-Triphenylphosphine Complexes Revisited: The Question of a Noninnocent Corrole". United States. doi:10.1021/acs.inorgchem.7b01828. https://www.osti.gov/servlets/purl/1462208.
@article{osti_1462208,
title = {Cobalt- and Rhodium-Corrole-Triphenylphosphine Complexes Revisited: The Question of a Noninnocent Corrole},
author = {Ganguly, Sumit and Renz, Diemo and Giles, Logan J. and Gagnon, Kevin J. and McCormick, Laura J. and Conradie, Jeanet and Sarangi, Ritimukta and Ghosh, Abhik},
abstractNote = {Here, a reinvestigation of cobalt-corrole-triphenylphosphine complexes has yielded an unexpectedly subtle picture of their electronic structures. UV-vis absorption spectroscopy, skeletal bond length alternations observed in X-ray structures, and broken-symmetry DFT (B3LYP) calculations suggest partial CoII-corrole•2– character for these complexes. The same methods applied to the analogous rhodium corroles evince no evidence of a noninnocent corrole. X-ray absorption spectroscopic studies showed that the Co K rising edge of Co[TPC](PPh3) (TPC = triphenylcorrole) is redshifted by ~1.8 eV relative to the bona fide Co(III) complexes Co[TPC](py)2 and Co[TPP](py)Cl (TPP = tetraphenylporphyrin, py = pyridine), consistent with a partial CoII-corrole•2– description for Co[TPC](PPh3). Electrochemical measurements have shown that both the Co and Rh complexes undergo two reversible oxidations and 1-2 irreversible reductions. In particular, the first reduction of the Rh corroles occurs at significantly more negative potentials than that of the Co corroles, reflecting significantly higher stability of the Rh(III) state relative to Co(III). Together, the results presented herein suggest that cobalt-corrole-triphenylphosphine complexes are significantly noninnocent with moderate CoII-corrole•2– character, underscoring – yet again – the ubiquity of ligand noninnocence among first-row transition metal corroles.},
doi = {10.1021/acs.inorgchem.7b01828},
journal = {Inorganic Chemistry},
number = 24,
volume = 56,
place = {United States},
year = {2017},
month = {12}
}