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Title: A New Approach to Non-Coordinating Anions: Lewis Acid Enhancement of Porphyrin Metal Centers in a Zwitterionic Metal$-$Organic Framework

Abstract

Here, we describe a new strategy to generate non-coordinating anions using zwitterionic metal–organic frameworks (MOFs). By assembly of anionic inorganic secondary building blocks (SBUs) ([In(CO 2) 4] $-$) with cationic metalloporphyrin-based organic linkers, we prepared zwitterionic MOFs in which the complete internal charge separation effectively prevents the potential binding of the counteranion to the cationic metal center. We demonstrate the enhanced Lewis acidity of Mn III- and Fe III-porphyrins in the zwitterionic MOFs in three representative electrocyclization reactions: [2 + 1] cycloisomerization of enynes, [3 + 2] cycloaddition of aziridines and alkenes, and [4 + 2] hetero-Diels–Alder cycloaddition of aldehydes with dienes. Lastly, this work paves a new way to design functional MOFs for tunable chemical catalysis.

Authors:
 [1];  [1];  [2];  [3];  [4];  [1]
  1. Univ. of Nebraska, Lincoln, NE (United States). Dept. of Chemistry
  2. Hungarian Academy of Sciences, Budapest (Hungary)
  3. Univ. of Nebraska, Lincoln, NE (United States). Dept. of Physics and Astronomy
  4. Univ. of Chicago, Argonne, IL (United States). ChemMatCARS, Center for Advanced Radiation Sources
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS)
Sponsoring Org.:
USDOE Office of Science (SC); National Science Foundation (NSF)
OSTI Identifier:
1345423
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Am. Chem. Soc.; Journal Volume: 138; Journal Issue: 32
Country of Publication:
United States
Language:
ENGLISH

Citation Formats

Johnson, Jacob A., Petersen, Brenna M., Kormos, Attila, Echeverría, Elena, Chen, Yu-Sheng, and Zhang, Jian. A New Approach to Non-Coordinating Anions: Lewis Acid Enhancement of Porphyrin Metal Centers in a Zwitterionic Metal$-$Organic Framework. United States: N. p., 2017. Web. doi:10.1021/jacs.6b05626.
Johnson, Jacob A., Petersen, Brenna M., Kormos, Attila, Echeverría, Elena, Chen, Yu-Sheng, & Zhang, Jian. A New Approach to Non-Coordinating Anions: Lewis Acid Enhancement of Porphyrin Metal Centers in a Zwitterionic Metal$-$Organic Framework. United States. doi:10.1021/jacs.6b05626.
Johnson, Jacob A., Petersen, Brenna M., Kormos, Attila, Echeverría, Elena, Chen, Yu-Sheng, and Zhang, Jian. Tue . "A New Approach to Non-Coordinating Anions: Lewis Acid Enhancement of Porphyrin Metal Centers in a Zwitterionic Metal$-$Organic Framework". United States. doi:10.1021/jacs.6b05626.
@article{osti_1345423,
title = {A New Approach to Non-Coordinating Anions: Lewis Acid Enhancement of Porphyrin Metal Centers in a Zwitterionic Metal$-$Organic Framework},
author = {Johnson, Jacob A. and Petersen, Brenna M. and Kormos, Attila and Echeverría, Elena and Chen, Yu-Sheng and Zhang, Jian},
abstractNote = {Here, we describe a new strategy to generate non-coordinating anions using zwitterionic metal–organic frameworks (MOFs). By assembly of anionic inorganic secondary building blocks (SBUs) ([In(CO2)4]$-$) with cationic metalloporphyrin-based organic linkers, we prepared zwitterionic MOFs in which the complete internal charge separation effectively prevents the potential binding of the counteranion to the cationic metal center. We demonstrate the enhanced Lewis acidity of MnIII- and FeIII-porphyrins in the zwitterionic MOFs in three representative electrocyclization reactions: [2 + 1] cycloisomerization of enynes, [3 + 2] cycloaddition of aziridines and alkenes, and [4 + 2] hetero-Diels–Alder cycloaddition of aldehydes with dienes. Lastly, this work paves a new way to design functional MOFs for tunable chemical catalysis.},
doi = {10.1021/jacs.6b05626},
journal = {J. Am. Chem. Soc.},
number = 32,
volume = 138,
place = {United States},
year = {Tue Feb 28 00:00:00 EST 2017},
month = {Tue Feb 28 00:00:00 EST 2017}
}
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