1
|
Southern SA, Perras FA. Comparison of methods for the NMR measurement of motionally averaged dipolar couplings. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2024; 364:107710. [PMID: 38901172 DOI: 10.1016/j.jmr.2024.107710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 05/31/2024] [Accepted: 06/07/2024] [Indexed: 06/22/2024]
Abstract
Motionally averaged dipolar couplings are an important tool for understanding the complex dynamics of catalysts, polymers, and biomolecules. While there is a plethora of solid-state NMR pulse sequences available for their measurement, in can be difficult to gauge the methods' strengths and weaknesses. In particular, there has not been a comprehensive comparison of their performance in natural abundance samples, where 1H homonuclear dipolar couplings are important and the use of large MAS rotors may be required for sensitivity reasons. In this work, we directly compared some of the more common methods for measuring C-H dipolar couplings in natural abundance samples using L-alanine (L-Ala) and the N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLF) tripeptide as model systems. We evaluated their performance in terms of accuracy, resolution, sensitivity, and ease of implementation. We found that, despite the presence of 1H homonuclear dipolar interactions, all methods, with the exception of REDOR, were able to yield the reasonable dipolar coupling strengths for both mobile and static moieties. Of these methods, PDLF provides the most convenient workflow and precision at the expense of low sensitivity. In low-sensitivity cases, MAS-PISEMA and DIPSHIFT appear to be the better options.
Collapse
Affiliation(s)
- Scott A Southern
- Chemical and Biological Sciences Division, Ames National Laboratory, Ames, IA 50011, USA
| | - Frédéric A Perras
- Chemical and Biological Sciences Division, Ames National Laboratory, Ames, IA 50011, USA; Department of Chemistry, Iowa State University, Ames, IA 50011, USA.
| |
Collapse
|
2
|
Southern SA, Liu DJ, Chatterjee P, Li Y, Perras FA. 1H chemical shift anisotropy: a high sensitivity solid-state NMR dynamics probe for surface studies? Phys Chem Chem Phys 2023; 25:5348-5360. [PMID: 36399032 DOI: 10.1039/d2cp04406d] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Dynamics play significant roles in chemistry and biochemistry-molecular motions impact both large- and small-scale chemical reactions in addition to biochemical processes. In many systems, including heterogeneous catalysts, the characterization of dynamics remains a challenge. The most common approaches involve the solid-state NMR measurement of anisotropic interactions, in particular 2H quadrupolar coupling and 1H-X dipolar coupling, which generally require isotope enrichment. Due to the high sensitivity of 1H NMR, 1H chemical shift anisotropy (CSA) is a particularly enticing, and underexplored, dynamics probe. We carried out 1H CSA and 1H-13C dipolar coupling measurements in a series of model supported complexes to understand how 1H CSA can be leveraged to gain dynamic information for heterogeneous catalysts. Mathematical descriptions are given for the dynamic averaging of the CSA tensor, and its dependence on orientation and asymmetry. The variability of the orientation of the tensor in the molecular frame, in addition to its magnitude and asymmetry, negatively impacts attempts to extract quantitative dynamic information. Nevertheless, 1H CSA measurements can reveal useful qualitative insights into the motions of a particularly dilute site, such as from a surface species.
Collapse
Affiliation(s)
- Scott A Southern
- Division of Chemical and Biological Sciences, Ames National Laboratory, Ames, IA 50014, USA.
| | - Da-Jiang Liu
- Division of Chemical and Biological Sciences, Ames National Laboratory, Ames, IA 50014, USA.
| | - Puranjan Chatterjee
- Division of Chemical and Biological Sciences, Ames National Laboratory, Ames, IA 50014, USA. .,Department of Chemistry, Iowa State University, Ames, IA 50014, USA
| | - Yuting Li
- Division of Chemical and Biological Sciences, Ames National Laboratory, Ames, IA 50014, USA.
| | - Frédéric A Perras
- Division of Chemical and Biological Sciences, Ames National Laboratory, Ames, IA 50014, USA.
| |
Collapse
|
3
|
Buntkowsky G, Döller S, Haro-Mares N, Gutmann T, Hoffmann M. Solid-state NMR studies of non-ionic surfactants confined in mesoporous silica. Z PHYS CHEM 2021. [DOI: 10.1515/zpch-2021-3132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Abstract
This review gives an overview of current trends in the investigation of confined molecules such as higher alcohols, ethylene glycol and polyethylene glycol as guest molecules in neat and functionalized mesoporous silica materials. All these molecules have both hydrophobic and hydrophilic parts. They are characteristic role-models for the investigation of confined surfactants. Their properties are studied by a combination of solid-state NMR and relaxometry with other physicochemical techniques and molecular dynamics techniques. It is shown that this combination delivers unique insights into the structure, arrangement, dynamical properties and the guest-host interactions inside the confinement.
Collapse
Affiliation(s)
- Gerd Buntkowsky
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Sonja Döller
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Nadia Haro-Mares
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Torsten Gutmann
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie , Technische Universität Darmstadt , Alarich-Weiss-Str. 8 , D-64287 Darmstadt , Germany
| | - Markus Hoffmann
- Department of Chemistry and Biochemistry , State University of New York College at Brockport , Brockport , NY , 14420 , USA
| |
Collapse
|
4
|
Iijima T, Ohki S, Tansho M. Separated quadrupole and shift interactions of 2H NMR spectra in paramagnetic solids by asymmetric pulse sequences. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2021; 112:101709. [PMID: 33494022 DOI: 10.1016/j.ssnmr.2020.101709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2020] [Revised: 12/10/2020] [Accepted: 12/10/2020] [Indexed: 06/12/2023]
Abstract
Separated pure-quadrupole (PQ) and -shift (PS) spectra of 2H nuclear magnetic resonance (NMR) of paramagnetic solids are obtained and correlated by simple pulse sequences that can acquire the full magnetization under ideal conditions. Two-dimensional NMR signals obtained using an asymmetric π-pulse-inserted quadrupole-echo (APIQE) sequence yielded separated spectra through the skew operation of an affine transform (AT) before a Fourier transform. Modified APIQE sequences that acquire whole echo signals were fabricated, and separated PQ and PS spectra were obtained by applying a combination of AT, such as rotation and skew operations, to the signal data. These methods were demonstrated for diamagnetic Zn(CD3CO2)2⋅2H2O and paramagnetic Nd(CD3CO2)3⋅1.5H2O. Further, the dynamics of the D2O molecule and [Co(D2O)6]2+ ion in paramagnetic CoSiF6⋅6D2O was analyzed based on the temperature dependence of the separated spectra.
Collapse
Affiliation(s)
- Takahiro Iijima
- Institute of Arts and Sciences, Yamagata University, Yamagata, 990-8560, Japan.
| | - Shinobu Ohki
- NMR Station, National Institute for Materials Science, Tsukuba, 305-0003, Japan
| | - Masataka Tansho
- NMR Station, National Institute for Materials Science, Tsukuba, 305-0003, Japan
| |
Collapse
|
5
|
Paterson AL, Liu DJ, Kanbur U, Sadow AD, Perras FA. Observing the three-dimensional dynamics of supported metal complexes. Inorg Chem Front 2021. [DOI: 10.1039/d0qi01241f] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The dynamics of heterogeneous catalysts are linked to their activity and selectivity but are poorly understood. NMR enables for the determination of high-resolution dynamic structures for such sites and the mapping of accessible conformations.
Collapse
|
6
|
Buntkowsky G, Vogel M. Small Molecules, Non-Covalent Interactions, and Confinement. Molecules 2020; 25:E3311. [PMID: 32708283 PMCID: PMC7397022 DOI: 10.3390/molecules25143311] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/07/2020] [Accepted: 07/15/2020] [Indexed: 11/27/2022] Open
Abstract
This review gives an overview of current trends in the investigation of small guest molecules, confined in neat and functionalized mesoporous silica materials by a combination of solid-state NMR and relaxometry with other physico-chemical techniques. The reported guest molecules are water, small alcohols, and carbonic acids, small aromatic and heteroaromatic molecules, ionic liquids, and surfactants. They are taken as characteristic role-models, which are representatives for the typical classes of organic molecules. It is shown that this combination delivers unique insights into the structure, arrangement, dynamics, guest-host interactions, and the binding sites in these confined systems, and is probably the most powerful analytical technique to probe these systems.
Collapse
Affiliation(s)
- Gerd Buntkowsky
- Institut für Physikalische Chemie, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Michael Vogel
- Institut für Festkörperphysik, Technische Universität Darmstadt, 64295 Darmstadt, Germany
| |
Collapse
|
7
|
Iijima T, Shimizu T. Separation of 2H NMR spectra assisted by molecular dynamics in diamagnetic and paramagnetic solids. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2018; 91:1-8. [PMID: 29549808 DOI: 10.1016/j.ssnmr.2018.03.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 03/05/2018] [Accepted: 03/05/2018] [Indexed: 06/08/2023]
Abstract
The relaxation-assisted separation method was applied to overlapping 2H nuclear magnetic resonance (NMR) spectra of diamagnetic and paramagnetic solids to separate them based on the different relaxation behaviors caused by molecular motion. Carr-Purcell-Meiboom-Gill sequences for 2H NMR were adopted to build two-dimensional data sets from one-dimensional NMR experiments. For diamagnetic α-glycine, the 2H NMR spectrum collected at 198 K was separated into two components from static -CD2- and dynamic -ND3. In addition, for the paramagnetic Sm(NO3)3·6D2O, the asymmetric 2H NMR spectra obtained at 213 K due to the hyperfine coupling was also separated into two components, which corresponded to coordinated and crystal water molecules undergoing a 180° flip motion with different correlation times.
Collapse
Affiliation(s)
- Takahiro Iijima
- Institute of Arts and Sciences, Yamagata University, Yamagata 990-8560, Japan.
| | - Tadashi Shimizu
- National Institute for Materials Science, Tsukuba 305-0003, Japan
| |
Collapse
|
8
|
Brownbill NJ, Gajan D, Lesage A, Emsley L, Blanc F. Oxygen-17 dynamic nuclear polarisation enhanced solid-state NMR spectroscopy at 18.8 T. Chem Commun (Camb) 2018; 53:2563-2566. [PMID: 28184389 DOI: 10.1039/c6cc09743j] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We report 17O dynamic nuclear polarisation (DNP) enhanced solid-state NMR experiments at 18.8 T. Several formulations were investigated on the Mg(OH)2 compound. A signal enhancement factor of 17 could be obtained when the solid particles were incorporated into a glassy o-terphenyl matrix doped with BDPA using the Overhauser polarisation transfer scheme whilst the cross effect mechanism enabled by TEKPol yielded a slightly lower enhancement but more time efficient data acquisition.
Collapse
Affiliation(s)
- Nick J Brownbill
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK.
| | - David Gajan
- Centre de RMN à Très Hauts Champs, Institut de Sciences Analytiques, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1), 69100 Villeurbanne, France
| | - Anne Lesage
- Centre de RMN à Très Hauts Champs, Institut de Sciences Analytiques, Université de Lyon (CNRS/ENS Lyon/UCB Lyon 1), 69100 Villeurbanne, France
| | - Lyndon Emsley
- Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Frédéric Blanc
- Department of Chemistry, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK. and Stephenson Institute for Renewable Energy, University of Liverpool, Crown Street, Liverpool, L69 7ZD, UK
| |
Collapse
|
9
|
Iijima T, Shimizu T. Deuterium off-magic-angle spinning NMR spectroscopy for pure-quadrupole spectra of paramagnetic solids. SOLID STATE NUCLEAR MAGNETIC RESONANCE 2017; 84:234-241. [PMID: 28676276 DOI: 10.1016/j.ssnmr.2017.06.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 06/22/2017] [Accepted: 06/22/2017] [Indexed: 06/07/2023]
Abstract
We examined a simple two-dimensional 2H nuclear magnetic resonance spectroscopy for paramagnetic solids utilizing off-magic-angle spinning (OMAS). By adding a rotor-synchronized 180° pulse to rotational echo (RE) measurement, the effect of the shift interaction was removed from the indirect dimension. The obtained pure-quadrupole spectrum could be simulated by calculating a quasi-one-dimensional NMR signal without considering the shift interaction. The sensitivity of the proposed method was compared with that of previous static NMR methods.
Collapse
Affiliation(s)
- Takahiro Iijima
- Institute of Arts and Sciences, Yamagata University, Yamagata 990-8560, Japan.
| | - Tadashi Shimizu
- National Institute for Materials Science, Tsukuba 305-0003, Japan
| |
Collapse
|
10
|
Meirovitch E, Liang Z, Freed JH. Protein dynamics in the solid state from 2H NMR line shape analysis: a consistent perspective. J Phys Chem B 2015; 119:2857-68. [PMID: 25594631 DOI: 10.1021/jp511386b] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Deuterium line shape analysis of CD3 groups has emerged as a particularly useful tool for studying microsecond-millisecond protein motions in the solid state. The models devised so far consist of several independently conceived simple jump-type motions. They are comprised of physical quantities encoded in their simplest form; improvements are only possible by adding yet another simple motion, thereby changing the model. The various treatments developed are case-specific; hence comparison among the different systems is not possible. Here we develop a new methodology for (2)H NMR line shape analysis free of these limitations. It is based on the microscopic-order-macroscopic-disorder (MOMD) approach. In MOMD motions are described by diffusion tensors, spatial restrictions by potentials/ordering tensors, and geometric features by relative tensor orientations. Jump-type motions are recovered in the limit of large orientational potentials. Model improvement is accomplished by monitoring the magnitude, symmetry, and orientation of the various tensors. The generality of MOMD makes possible comparison among different scenarios. CD3 line shapes from the Chicken Villin Headpiece Subdomain and the Streptomyces Subtilisin Inhibitor are used as experimental examples. All of these spectra are reproduced by using rhombic local potentials constrained for simplicity to be given by the L = 2 spherical harmonics, and by axial diffusion tensors. Potential strength and rhombicity are found to be ca. 2-3 k(B)T. The diffusion tensor is tilted at 120° from the C-CD3 axis. The perpendicular (parallel) correlation times for local motion are 0.1-1.0 ms (3.3-30 μs). Activation energies in the 1.1-8.0 kcal/mol range are estimated. Future prospects include extension to the (2)H relaxation limit, application to the (15)N and (13)C NMR nuclei, and accounting for collective motions and anisotropic media.
Collapse
Affiliation(s)
- Eva Meirovitch
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University , Ramat-Gan 52900, Israel
| | | | | |
Collapse
|
11
|
Iijima T, Shimizu T, Nishimura K. 2H NMR pure-quadrupole spectra for paramagnetic solids. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2015; 251:57-64. [PMID: 25562570 DOI: 10.1016/j.jmr.2014.11.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 11/13/2014] [Accepted: 11/16/2014] [Indexed: 06/04/2023]
Abstract
We report a simple two-dimensional NMR method for obtaining (2)H NMR pure-quadrupole spectra of paramagnetic solids. This method is based on a quadrupole-echo sequence inserted with 180° pulses, where the pulse spacings are incremented asymmetrically so that the (2)H magnetization evolves only by the quadrupole interaction in the indirect dimension. It is shown that when the sequence is carried out with strong radio-frequency pulses, the spectrum projected to the indirect dimension can be simulated using the quadrupole-echo sequence without considering the effect of the paramagnetic shift. The method was also used to investigate molecular dynamics by measurement and simulation of the temperature dependence of the (2)H NMR spectra.
Collapse
Affiliation(s)
- Takahiro Iijima
- Institute of Arts and Sciences, Yamagata University, Yamagata 990-8560, Japan.
| | - Tadashi Shimizu
- National Institute for Materials Science, Tsukuba 305-0003, Japan
| | | |
Collapse
|
12
|
Li K, Emani PS, Ash J, Groves M, Drobny GP. A study of phenylalanine side-chain dynamics in surface-adsorbed peptides using solid-state deuterium NMR and rotamer library statistics. J Am Chem Soc 2014; 136:11402-11. [PMID: 25054469 DOI: 10.1021/ja504677d] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Extracellular matrix proteins adsorbed onto mineral surfaces exist in a unique environment where the structure and dynamics of the protein can be altered profoundly. To further elucidate how the mineral surface impacts molecular properties, we perform a comparative study of the dynamics of nonpolar side chains within the mineral-recognition domain of the biomineralization protein salivary statherin adsorbed onto its native hydroxyapatite (HAP) mineral surface versus the dynamics displayed by the native protein in the hydrated solid state. Specifically, the dynamics of phenylalanine side chains (viz., F7 and F14) located in the surface-adsorbed 15-amino acid HAP-recognition fragment (SN15: DpSpSEEKFLRRIGRFG) are studied using deuterium magic angle spinning ((2)H MAS) line shape and spin-lattice relaxation measurements. (2)H NMR MAS spectra and T1 relaxation times obtained from the deuterated phenylalanine side chains in free and HAP-adsorbed SN15 are fitted to models where the side chains are assumed to exchange between rotameric states and where the exchange rates and a priori rotameric state populations are varied iteratively. In condensed proteins, phenylalanine side-chain dynamics are dominated by 180° flips of the phenyl ring, i.e., the "π flip". However, for both F7 and F14, the number of exchanging side-chain rotameric states increases in the HAP-bound complex relative to the unbound solid sample, indicating that increased dynamic freedom accompanies introduction of the protein into the biofilm state. The observed rotameric exchange dynamics in the HAP-bound complex are on the order of 5-6 × 10(6) s(-1), as determined from the deuterium MAS line shapes. The dynamics in the HAP-bound complex are also shown to have some solution-like behavioral characteristics, with some interesting deviations from rotameric library statistics.
Collapse
Affiliation(s)
- Kun Li
- Department of Chemistry, University of Washington , Box 351700, Seattle, Washington 98195, United States
| | | | | | | | | |
Collapse
|
13
|
Smart KA, Mothes-Martin E, Annaka T, Grellier M, Sabo-Etienne S. Silane Deuteration Catalyzed by Ruthenium Bis(dihydrogen) Complexes or Simple Metal Salts. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201300902] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
14
|
Werner M, Rothermel N, Breitzke H, Gutmann T, Buntkowsky G. Recent Advances in Solid State NMR of Small Molecules in Confinement. Isr J Chem 2014. [DOI: 10.1002/ijch.201300095] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
15
|
Smart KA, Grellier M, Coppel Y, Vendier L, Mason SA, Capelli SC, Albinati A, Montiel-Palma V, Muñoz-Hernández MA, Sabo-Etienne S. Nature of Si-H interactions in a series of ruthenium silazane complexes using multinuclear solid-state NMR and neutron diffraction. Inorg Chem 2014; 53:1156-65. [PMID: 24392827 DOI: 10.1021/ic4027199] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Three new N-heterocyclic-silazane compounds, 1a-c, were prepared and employed as bidentate ligands to ruthenium, resulting in a series of [Ru(H){(κ-Si,N-(SiMe2-N-heterocycle)}3] complexes (3a-c) featuring the same RuSi3H motif. Detailed structural characterization of the RuSi3H complexes with X-ray diffraction, and in the case of triazabicyclo complex [Ru(H){κ-Si,N-(SiMe2)(C7H12N3)}3] (3a), neutron diffraction, enabled a reliable description of the molecular geometry. The hydride ligand of (3a) is located closer to two of the silicon atoms than it is to the third. Such a geometry differs from that of the previously reported complex [Ru(H){(κ-Si,N-(SiMe2)N(SiMe2H)(C5H4N)}3] (3d), also characterized by neutron diffraction, where the hydride was found to be equidistant from all three silicon atoms. A DFT study revealed that the symmetric and less regular isomers are essentially degenerate. Information on the dynamics and on the Ru···H···Si interactions was gained from multinuclear solid-state ((1)H wPMLG, (29)Si CP MAS, and 2D (1)H-(29)Si dipolar HETCOR experiments) and solution NMR studies. The corresponding intermediate complexes, [Ru{κ-Si,N-(SiMe2-N-heterocycle)}(η(4)-C8H12)(η(3)-C8H11)] (2a-c), involving a single silazane ligand were isolated and characterized by multinuclear NMR and X-ray diffraction. Protonation of the RuSi3H complexes was also studied. Reaction of 3a with NH4PF6 gave rise to [Ru(H)(η(2)-H -SiMe2)κ-N-(C7H12N3){κ-Si,N-(SiMe2)(C7H12N3)}2](+)[PF6](-)(4aPF6) which was isolated and characterized by NMR spectroscopy, X-ray crystallography, and DFT studies. The nature of the Si-H interactions in this silazane series was analyzed in detail.
Collapse
Affiliation(s)
- Katharine A Smart
- LCC (Laboratoire de Chimie de Coordination), CNRS , 205 Route de Narbonne, F-31077 Toulouse, France
| | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Alonso B, Marichal C. Solid-state NMR studies of micelle-templated mesoporous solids. Chem Soc Rev 2013; 42:3808-20. [DOI: 10.1039/c2cs35368g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
17
|
Grellier M, Mason SA, Albinati A, Capelli SC, Rizzato S, Bijani C, Coppel Y, Sabo-Etienne S. Probing Highly Selective H/D Exchange Processes with a Ruthenium Complex through Neutron Diffraction and Multinuclear NMR Studies. Inorg Chem 2012; 52:7329-37. [DOI: 10.1021/ic302307m] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Mary Grellier
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
| | - Sax A. Mason
- Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble Cedex 9, France
| | - Alberto Albinati
- Dipartimento di Chimica, Università di Milano, Via C. Golgi, 19, 20133
Milan, Italy
| | - Silvia C. Capelli
- Institut Laue-Langevin, 6 rue Jules Horowitz, BP 156, 38042 Grenoble Cedex 9, France
| | - Silvia Rizzato
- Dipartimento di Chimica, Università di Milano, Via C. Golgi, 19, 20133
Milan, Italy
| | - Christian Bijani
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
| | - Yannick Coppel
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
| | - Sylviane Sabo-Etienne
- CNRS, LCC (Laboratoire de Chimie de Coordination),
205 route de Narbonne, BP 44099, F-31077 Toulouse Cedex 4, France
- Université de Toulouse, UPS, INPT, F-31077 Toulouse Cedex 4, France
| |
Collapse
|
18
|
Iijima T, Nishimura K. 2H quadrupolar Carr-Purcell-Meiboom-Gill NMR for paramagnetic solids. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.08.058] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
|
19
|
Breen NF, Li K, Olsen GL, Drobny GP. Deuterium magic angle spinning NMR used to study the dynamics of peptides adsorbed onto polystyrene and functionalized polystyrene surfaces. J Phys Chem B 2011; 115:9452-60. [PMID: 21650191 DOI: 10.1021/jp1101829] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
LKα14 is a 14 amino acid peptide with a periodic sequence of leucine and lysine residues consistent with an amphipathic α-helix. This "hydrophobic periodicity" has been found to result in an α-helical secondary structure at air-water interfaces and on both polar and nonpolar solid polymer surfaces. In this paper, the dynamics of LKα14 peptides, selectively deuterated at a single leucine and adsorbed onto polystyrene and carboxylated polystyrene beads, are studied using (2)H magic angle spinning (MAS) solid state NMR over a 100 °C temperature range. We first demonstrate the sensitivity enhancement possible with (2)H MAS techniques, which in turn enables us to obtain high-quality (2)H NMR spectra for selectively deuterated peptides adsorbed onto solid polymer surfaces. The extensive literature shows that the dynamics of leucine side chains are sensitive to the local structural environment of the protein. Therefore, the degree to which the dynamics of leucine side chains and the backbone of the peptide LKα14 are influenced by surface proximity and surface chemistry is studied as a function of temperature with (2)H MAS NMR. It is found that the dynamics of the leucine side chains in LKα14 depend strongly upon the orientation of the polymer on the surface, which in turn depends on whether the LKα14 peptide adsorbs onto a polar or nonpolar surface. (2)H MAS line shapes therefore permit probes of surface orientation over a wide temperature range.
Collapse
Affiliation(s)
- Nicholas F Breen
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | | | | | | |
Collapse
|
20
|
Nishchenko AM, Kolokolov DI, Stepanov AG. Mobility of Solid tert-Butyl Alcohol Studied by Deuterium NMR. J Phys Chem A 2011; 115:7428-36. [DOI: 10.1021/jp203353x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Alena M. Nishchenko
- Faculty of Physics, Department of Chemical and Biological Physics, Novosibirsk State University, Pirogova Street 2, Novosibirsk 630090, Russia
| | - Daniil I. Kolokolov
- Boreskov Institute of Catalysis, Siberian Branch of Russian Academy of Sciences, Prospekt Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| | - Alexander G. Stepanov
- Boreskov Institute of Catalysis, Siberian Branch of Russian Academy of Sciences, Prospekt Akademika Lavrentieva 5, Novosibirsk 630090, Russia
| |
Collapse
|
21
|
Gajan D, Levine D, Zocher E, Copéret C, Lesage A, Emsley L. Probing surface site heterogeneity through 1D and INADEQUATE 31P solid state NMR spectroscopy of silica supported PMe3-Au(I) adducts. Chem Sci 2011. [DOI: 10.1039/c0sc00579g] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
22
|
Rascón F, Wischert R, Copéret C. Molecular nature of support effects in single-site heterogeneous catalysts: silica vs. alumina. Chem Sci 2011. [DOI: 10.1039/c1sc00073j] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
23
|
Accessibility and Interaction of Surface OH Groups in Microporous and Mesoporous Catalysts Applied for Vapor-Phase Beckmann Rearrangement of Oximes. Catal Letters 2010. [DOI: 10.1007/s10562-010-0274-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
24
|
Griffin JM, Miller AJ, Berry AJ, Wimperis S, Ashbrook SE. Dynamics on the microsecond timescale in hydrous silicates studied by solid-state 2H NMR spectroscopy. Phys Chem Chem Phys 2010; 12:2989-98. [DOI: 10.1039/b924666e] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|