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Title: β-Octabromo- and β-Octakis(trifluoromethyl)isocorroles: New Sterically Constrained Macrocyclic Ligands

Abstract

Here, we present a study of the acid-induced demetalation of two sterically hindered copper corroles, Cu β-octabromo-meso-triphenylcorrole (Cu[Br 8TPC]) and β-octakis(trifluoromethyl)-meso-tris(p-methoxyphenyl)corrole (Cu[(CF 3) 8TpOMePC]). Unlike reductive demetalation, which affords the free-base β-octabromocorrole, demetalation of Cu[Br 8TPC] under non- reductive conditions (CHCl 3/H 2SO 4) resulted in moderate yields of free-base 5- and 10-hydroxy isocorroles. The isomeric free bases could be complexed to Co II and Ni II, affording stable complexes. Only reductive demetalation was found to work for Cu[(CF 3) 8TpOMePC], affording a highly saddled, hydrated corrole, H 3[5-OH,10-H-(CF 3) 8TpOMePC], where the elements of water had added across C5 and C10. Interaction of this novel free base with Co II resulted in Co[iso-10-H-[CF 3) 8TpOMePC], a Co II 10-hydro isocorrole. Finally, the new metal complexes were all characterized by single-crystal X-ray diffraction analysis and, despite their sterically hindered nature, were found to exhibit almost perfectly planar isocorrole cores.

Authors:
 [1];  [2];  [2]; ORCiD logo [1]
  1. Arctic Univ. of Norway, Tromso (Norway). Dept. of Chemistry, Center for Theoretical and Computational Chemistry
  2. Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Advanced Light Source
Publication Date:
Research Org.:
Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1413727
Grant/Contract Number:
AC02-05CH11231
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
ChemistryOpen
Additional Journal Information:
Journal Volume: 6; Journal Issue: 3; Journal ID: ISSN 2191-1363
Publisher:
ChemPubSoc Europe
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; corroles; isocorroles; macrocyclic ligands; near-infrared; single-crystal x-ray crystallography

Citation Formats

Thomas, Kolle E., Beavers, Christine M., Gagnon, Kevin J., and Ghosh, Abhik. β-Octabromo- and β-Octakis(trifluoromethyl)isocorroles: New Sterically Constrained Macrocyclic Ligands. United States: N. p., 2017. Web. doi:10.1002/open.201700035.
Thomas, Kolle E., Beavers, Christine M., Gagnon, Kevin J., & Ghosh, Abhik. β-Octabromo- and β-Octakis(trifluoromethyl)isocorroles: New Sterically Constrained Macrocyclic Ligands. United States. doi:10.1002/open.201700035.
Thomas, Kolle E., Beavers, Christine M., Gagnon, Kevin J., and Ghosh, Abhik. Fri . "β-Octabromo- and β-Octakis(trifluoromethyl)isocorroles: New Sterically Constrained Macrocyclic Ligands". United States. doi:10.1002/open.201700035. https://www.osti.gov/servlets/purl/1413727.
@article{osti_1413727,
title = {β-Octabromo- and β-Octakis(trifluoromethyl)isocorroles: New Sterically Constrained Macrocyclic Ligands},
author = {Thomas, Kolle E. and Beavers, Christine M. and Gagnon, Kevin J. and Ghosh, Abhik},
abstractNote = {Here, we present a study of the acid-induced demetalation of two sterically hindered copper corroles, Cu β-octabromo-meso-triphenylcorrole (Cu[Br8TPC]) and β-octakis(trifluoromethyl)-meso-tris(p-methoxyphenyl)corrole (Cu[(CF3)8TpOMePC]). Unlike reductive demetalation, which affords the free-base β-octabromocorrole, demetalation of Cu[Br8TPC] under non- reductive conditions (CHCl3/H2SO4) resulted in moderate yields of free-base 5- and 10-hydroxy isocorroles. The isomeric free bases could be complexed to CoII and NiII, affording stable complexes. Only reductive demetalation was found to work for Cu[(CF3)8TpOMePC], affording a highly saddled, hydrated corrole, H3[5-OH,10-H-(CF3)8TpOMePC], where the elements of water had added across C5 and C10. Interaction of this novel free base with CoII resulted in Co[iso-10-H-[CF3)8TpOMePC], a CoII 10-hydro isocorrole. Finally, the new metal complexes were all characterized by single-crystal X-ray diffraction analysis and, despite their sterically hindered nature, were found to exhibit almost perfectly planar isocorrole cores.},
doi = {10.1002/open.201700035},
journal = {ChemistryOpen},
number = 3,
volume = 6,
place = {United States},
year = {Fri May 26 00:00:00 EDT 2017},
month = {Fri May 26 00:00:00 EDT 2017}
}

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