Obtaining detailed structural information of reaction intermediates remains a key challenge in heterogeneous catalysis because of the amorphous nature of the support and/or the support interface that prohibits the use of diffraction-based techniques. Combining isotopic labeling and dynamic nuclear polarization (DNP) increases the sensitivity of surface enhanced solid-state NMR spectroscopy (SENS) towards surface species in heterogeneous alkene metathesis catalysts; this in turn allows direct determination of the bond connectivity and measurement of the carbon-carbon bond distance in metallacycles, which are the cycloaddition intermediates in the alkene metathesis catalytic cycle. Furthermore, this approach makes possible the understanding of the slow initiation and deactivation steps in these heterogeneous metathesis catalysts.
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Identifying low-coverage surface species on supported noble metal nanoparticle catalysts by DNP-NMR #DNPNMR
From The DNP-NMR Blog:
Identifying low-coverage surface species on supported noble metal nanoparticle catalysts by DNP-NMR #DNPNMR
Johnson, R.L., et al., Identifying low-coverage surface species on supported noble metal nanoparticle catalysts by DNP-NMR. Chem Commun (Camb), 2016. 52(9): p. 1859-62.
http://www.ncbi.nlm.nih.gov/pubmed/26675287
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06-03-2016 04:52 PM
[NMR paper] Characterization of photo-intermediates in the photo-reaction pathways of a bacteriorhodopsin Y185F mutant using in situ photo-irradiation solid-state NMR spectroscopy.
Characterization of photo-intermediates in the photo-reaction pathways of a bacteriorhodopsin Y185F mutant using in situ photo-irradiation solid-state NMR spectroscopy.
http://www.bionmr.com//www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.rsc.org-images-entities-char_z_RSClogo.gif Related Articles Characterization of photo-intermediates in the photo-reaction pathways of a bacteriorhodopsin Y185F mutant using in situ photo-irradiation solid-state NMR spectroscopy.
Photochem Photobiol Sci. 2015 Sep 26;14(9):1694-702
Authors: Oshima K, Shigeta A,...
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06-01-2016 11:08 AM
Elucidatingthe Link between NMR Chemical Shifts andElectronic Structure in d0 Olefin Metathesis Catalysts
Elucidatingthe Link between NMR Chemical Shifts andElectronic Structure in d0 Olefin Metathesis Catalysts
Ste?phanie Halbert, Christophe Cope?ret, Christophe Raynaud and Odile Eisenstein
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/jacs.5b12597/20160209/images/medium/ja-2015-12597d_0011.gif
Journal of the American Chemical Society
DOI: 10.1021/jacs.5b12597
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA
http://feeds.feedburner.com/~r/acs/jacsat/~4/G_LlapGatAI
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02-10-2016 08:05 AM
[NMR paper] Atomistic insights into human Cys-loop receptors by solution NMR.
Atomistic insights into human Cys-loop receptors by solution NMR.
http://www.bionmr.com//www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles Atomistic insights into human Cys-loop receptors by solution NMR.
Biochim Biophys Acta. 2015 Jan;1848(1 Pt B):307-14
Authors: Mowrey DD, Kinde MN, Xu Y, Tang P
Abstract
Cys-loop receptors are pentameric ligand-gated ion channels (pLGICs) mediating fast neurotransmission in the central and peripheral nervous systems. They are...
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02-13-2015 05:31 PM
Silica-surface reorganization during organotin grafting evidenced by 119Sn DNP SENS: a tandem reaction of gem-silanols and strained siloxane bridges
From The DNP-NMR Blog:
Silica-surface reorganization during organotin grafting evidenced by 119Sn DNP SENS: a tandem reaction of gem-silanols and strained siloxane bridges
Conley, M.P., et al., Silica-surface reorganization during organotin grafting evidenced by 119Sn DNP SENS: a tandem reaction of gem-silanols and strained siloxane bridges. Phys. Chem. Chem. Phys., 2014. 16(33): p. 17822-17827.
http://dx.doi.org/10.1039/C4CP01973C
Grafting reactive molecular complexes on dehydroxylated amorphous silica is a strategy to develop "single-site" heterogeneous catalysts. In...
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08-06-2014 08:39 PM
[NMR paper] Catalytic mechanism of ?-phosphate attack in dUTPase is revealed by X-ray crystallographic snapshots of distinct intermediates, 31P-NMR spectroscopy and reaction path modelling.
Catalytic mechanism of ?-phosphate attack in dUTPase is revealed by X-ray crystallographic snapshots of distinct intermediates, 31P-NMR spectroscopy and reaction path modelling.
Catalytic mechanism of ?-phosphate attack in dUTPase is revealed by X-ray crystallographic snapshots of distinct intermediates, 31P-NMR spectroscopy and reaction path modelling.
Nucleic Acids Res. 2013 Aug 27;
Authors: Barabás O, Németh V, Bodor A, Perczel A, Rosta E, Kele Z, Zagyva I, Szabadka Z, Grolmusz VI, Wilmanns M, Vértessy BG
Abstract
Enzymatic synthesis...
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08-29-2013 01:53 PM
17O NMR Gives Unprecedented Insights into the Structure of Supported Catalysts and Their Interaction with the Silica Carrier
17O NMR Gives Unprecedented Insights into the Structure of Supported Catalysts and Their Interaction with the Silica Carrier
Nicolas Merle, Julien Tre?bosc, Anne Baudouin, Iker Del Rosal, Laurent Maron, Kai Szeto, Marie Genelot, Andre? Mortreux, Mostafa Taoufik, Laurent Delevoye and Re?gis M. Gauvin
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja301085m/aop/images/medium/ja-2012-01085m_0017.gif
Journal of the American Chemical Society
DOI: 10.1021/ja301085m
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA ...
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05-25-2012 07:14 PM
[NMR paper] Identification of reaction products and intermediates of aromatic-amine dehydrogenase
Identification of reaction products and intermediates of aromatic-amine dehydrogenase by 15N and 13C NMR.
Related Articles Identification of reaction products and intermediates of aromatic-amine dehydrogenase by 15N and 13C NMR.
Biochem J. 1998 Mar 15;330 ( Pt 3):1159-63
Authors: Bishop GR, Zhu Z, Whitehead TL, Hicks RP, Davidson VL
13C- and 15N-NMR studies of the reaction of aromatic amine dehydrogenase (AADH) with methylamine demonstrated that the products of the reductive half-reaction are an equivalent of formaldehyde hydrate and a reduced...