Dihydrogen complexes of metalloporphyrins: Characterization and catalytic hydrogen oxidation activity

James P. Collman, Paul S. Wagenknecht, James E. Hutchison, Nathan S Lewis, Michel Angel Lopez, Roger Guilard, Maurice L'Her, Aksel A. Bothner-By, P. K. Mishra

Research output: Contribution to journalArticle

71 Citations (Scopus)

Abstract

A series of monometallic dihydrogen complexes of the type M(OEP)(L)(H2) (M = Ru, Os; L = THF, *Im) was synthesized and characterized by 1H NMR. The H-H bond length was found to increase when Os was replaced by Ru or when *Im was replaced by THF. The bond distances (as determined by T1) range from 0.92 to 1.18 Å. The first example of a bimetallic bridging dihydrogen complex, Ru2(DPB)(*Im)2(H2), was also prepared. The H2 ligand is simultaneously bound to both Ru-metal centers. High-field 1H NMR experiments (620 MHz) revealed a -7.37 Hz dipolar splitting of the H2 ligand for this complex. Analysis of this splitting suggests that the H2 ligand is bound with the H-H axis perpendicular to the Ru-Ru axis. These complexes were examined as possible catalysts for the oxidation of dihydrogen through prior heterolytic activation of H2. Only Ru(OEP)(THF)(H2) can be conveniently deprotonated. Ru(OEP)(THF)(H2) is also implicated in the Ru-(OEP)(THF)2 catalyzed isotopic exchange between H2 and D2O in THF solution. Each step for this mechanism has been elucidated. We have also achieved catalytic dihydrogen oxidation using [Ru(OEP)]2 adsorbed onto graphite. Two mechanisms for this ruthenium porphyrin catalyzed dihydrogen oxidation are presented and compared.

Original languageEnglish
Pages (from-to)5654-5664
Number of pages11
JournalJournal of the American Chemical Society
Volume114
Issue number14
Publication statusPublished - 1992

Fingerprint

Metalloporphyrins
Hydrogen
Ligands
Oxidation
Nuclear magnetic resonance
Ruthenium
Graphite
Catalytic oxidation
Porphyrins
Bond length
Ion exchange
Metals
Chemical activation
Catalysts
Experiments
Proton Magnetic Resonance Spectroscopy

ASJC Scopus subject areas

  • Chemistry(all)

Cite this

Collman, J. P., Wagenknecht, P. S., Hutchison, J. E., Lewis, N. S., Lopez, M. A., Guilard, R., ... Mishra, P. K. (1992). Dihydrogen complexes of metalloporphyrins: Characterization and catalytic hydrogen oxidation activity. Journal of the American Chemical Society, 114(14), 5654-5664.

Dihydrogen complexes of metalloporphyrins : Characterization and catalytic hydrogen oxidation activity. / Collman, James P.; Wagenknecht, Paul S.; Hutchison, James E.; Lewis, Nathan S; Lopez, Michel Angel; Guilard, Roger; L'Her, Maurice; Bothner-By, Aksel A.; Mishra, P. K.

In: Journal of the American Chemical Society, Vol. 114, No. 14, 1992, p. 5654-5664.

Research output: Contribution to journalArticle

Collman, JP, Wagenknecht, PS, Hutchison, JE, Lewis, NS, Lopez, MA, Guilard, R, L'Her, M, Bothner-By, AA & Mishra, PK 1992, 'Dihydrogen complexes of metalloporphyrins: Characterization and catalytic hydrogen oxidation activity', Journal of the American Chemical Society, vol. 114, no. 14, pp. 5654-5664.
Collman, James P. ; Wagenknecht, Paul S. ; Hutchison, James E. ; Lewis, Nathan S ; Lopez, Michel Angel ; Guilard, Roger ; L'Her, Maurice ; Bothner-By, Aksel A. ; Mishra, P. K. / Dihydrogen complexes of metalloporphyrins : Characterization and catalytic hydrogen oxidation activity. In: Journal of the American Chemical Society. 1992 ; Vol. 114, No. 14. pp. 5654-5664.
@article{5120d809ec74440bb5cad9a32bcd72b6,
title = "Dihydrogen complexes of metalloporphyrins: Characterization and catalytic hydrogen oxidation activity",
abstract = "A series of monometallic dihydrogen complexes of the type M(OEP)(L)(H2) (M = Ru, Os; L = THF, *Im) was synthesized and characterized by 1H NMR. The H-H bond length was found to increase when Os was replaced by Ru or when *Im was replaced by THF. The bond distances (as determined by T1) range from 0.92 to 1.18 {\AA}. The first example of a bimetallic bridging dihydrogen complex, Ru2(DPB)(*Im)2(H2), was also prepared. The H2 ligand is simultaneously bound to both Ru-metal centers. High-field 1H NMR experiments (620 MHz) revealed a -7.37 Hz dipolar splitting of the H2 ligand for this complex. Analysis of this splitting suggests that the H2 ligand is bound with the H-H axis perpendicular to the Ru-Ru axis. These complexes were examined as possible catalysts for the oxidation of dihydrogen through prior heterolytic activation of H2. Only Ru(OEP)(THF)(H2) can be conveniently deprotonated. Ru(OEP)(THF)(H2) is also implicated in the Ru-(OEP)(THF)2 catalyzed isotopic exchange between H2 and D2O in THF solution. Each step for this mechanism has been elucidated. We have also achieved catalytic dihydrogen oxidation using [Ru(OEP)]2 adsorbed onto graphite. Two mechanisms for this ruthenium porphyrin catalyzed dihydrogen oxidation are presented and compared.",
author = "Collman, {James P.} and Wagenknecht, {Paul S.} and Hutchison, {James E.} and Lewis, {Nathan S} and Lopez, {Michel Angel} and Roger Guilard and Maurice L'Her and Bothner-By, {Aksel A.} and Mishra, {P. K.}",
year = "1992",
language = "English",
volume = "114",
pages = "5654--5664",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "14",

}

TY - JOUR

T1 - Dihydrogen complexes of metalloporphyrins

T2 - Characterization and catalytic hydrogen oxidation activity

AU - Collman, James P.

AU - Wagenknecht, Paul S.

AU - Hutchison, James E.

AU - Lewis, Nathan S

AU - Lopez, Michel Angel

AU - Guilard, Roger

AU - L'Her, Maurice

AU - Bothner-By, Aksel A.

AU - Mishra, P. K.

PY - 1992

Y1 - 1992

N2 - A series of monometallic dihydrogen complexes of the type M(OEP)(L)(H2) (M = Ru, Os; L = THF, *Im) was synthesized and characterized by 1H NMR. The H-H bond length was found to increase when Os was replaced by Ru or when *Im was replaced by THF. The bond distances (as determined by T1) range from 0.92 to 1.18 Å. The first example of a bimetallic bridging dihydrogen complex, Ru2(DPB)(*Im)2(H2), was also prepared. The H2 ligand is simultaneously bound to both Ru-metal centers. High-field 1H NMR experiments (620 MHz) revealed a -7.37 Hz dipolar splitting of the H2 ligand for this complex. Analysis of this splitting suggests that the H2 ligand is bound with the H-H axis perpendicular to the Ru-Ru axis. These complexes were examined as possible catalysts for the oxidation of dihydrogen through prior heterolytic activation of H2. Only Ru(OEP)(THF)(H2) can be conveniently deprotonated. Ru(OEP)(THF)(H2) is also implicated in the Ru-(OEP)(THF)2 catalyzed isotopic exchange between H2 and D2O in THF solution. Each step for this mechanism has been elucidated. We have also achieved catalytic dihydrogen oxidation using [Ru(OEP)]2 adsorbed onto graphite. Two mechanisms for this ruthenium porphyrin catalyzed dihydrogen oxidation are presented and compared.

AB - A series of monometallic dihydrogen complexes of the type M(OEP)(L)(H2) (M = Ru, Os; L = THF, *Im) was synthesized and characterized by 1H NMR. The H-H bond length was found to increase when Os was replaced by Ru or when *Im was replaced by THF. The bond distances (as determined by T1) range from 0.92 to 1.18 Å. The first example of a bimetallic bridging dihydrogen complex, Ru2(DPB)(*Im)2(H2), was also prepared. The H2 ligand is simultaneously bound to both Ru-metal centers. High-field 1H NMR experiments (620 MHz) revealed a -7.37 Hz dipolar splitting of the H2 ligand for this complex. Analysis of this splitting suggests that the H2 ligand is bound with the H-H axis perpendicular to the Ru-Ru axis. These complexes were examined as possible catalysts for the oxidation of dihydrogen through prior heterolytic activation of H2. Only Ru(OEP)(THF)(H2) can be conveniently deprotonated. Ru(OEP)(THF)(H2) is also implicated in the Ru-(OEP)(THF)2 catalyzed isotopic exchange between H2 and D2O in THF solution. Each step for this mechanism has been elucidated. We have also achieved catalytic dihydrogen oxidation using [Ru(OEP)]2 adsorbed onto graphite. Two mechanisms for this ruthenium porphyrin catalyzed dihydrogen oxidation are presented and compared.

UR - http://www.scopus.com/inward/record.url?scp=0000910791&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0000910791&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0000910791

VL - 114

SP - 5654

EP - 5664

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 14

ER -