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Serenko O, Skupov K, Bakirov A, Kuchkina N, Shifrina Z, Muzafarov A. Porosity of Rigid Dendrimers in Bulk: Interdendrimer Interactions and Functionality as Key Factors. NANOMATERIALS 2021; 11:nano11102600. [PMID: 34685040 PMCID: PMC8537161 DOI: 10.3390/nano11102600] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 09/30/2021] [Indexed: 01/17/2023]
Abstract
The porous structure of second- and third-generation polyphenylene-type dendrimers was investigated by adsorption of N2, Ar, and CO2 gases, scanning electron microscopy and small-angle X-ray spectroscopy. Rigid dendrimers in bulk are microporous and demonstrate a molecular sieve effect. When using CO2 as an adsorbate gas, the pore size varies from 0.6 to 0.9 nm. This is most likely due to the distances between dendrimer macromolecules or branches of neighboring dendrimers, whose packing is mostly realized due to intermolecular interactions, in particular, π-π interactions of aromatic fragments. Intermolecular interactions prevent the manifestation of the porosity potential inherent to the molecular 3D structure of third-generation dendrimers, while for the second generation, much higher porosity is observed. The maximum specific surface area for the second-generation dendrimers was 467 m2/g when measured by CO2 adsorption, indicating that shorter branches of these dendrimers do not provide dense packing. This implies that the possible universal method to create porous materials for all kinds of rigid dendrimers is by a placement of bulky substituents in their outer layer.
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Affiliation(s)
- Olga Serenko
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilova St., GSP-1, V-334, 119991 Moscow, Russia; (K.S.); (N.K.); (Z.S.); (A.M.)
- Correspondence:
| | - Kirill Skupov
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilova St., GSP-1, V-334, 119991 Moscow, Russia; (K.S.); (N.K.); (Z.S.); (A.M.)
| | - Artem Bakirov
- N.S. Enikolopov Institute of Synthetic Polymeric Materials, Russian Academy of Sciences, 117393 Moscow, Russia;
| | - Nina Kuchkina
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilova St., GSP-1, V-334, 119991 Moscow, Russia; (K.S.); (N.K.); (Z.S.); (A.M.)
| | - Zinaida Shifrina
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilova St., GSP-1, V-334, 119991 Moscow, Russia; (K.S.); (N.K.); (Z.S.); (A.M.)
| | - Aziz Muzafarov
- A.N. Nesmeyanov Institute of Organoelement Compounds of Russian Academy of Sciences, 28 Vavilova St., GSP-1, V-334, 119991 Moscow, Russia; (K.S.); (N.K.); (Z.S.); (A.M.)
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2
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Markelov DA, Semisalova AS, Mazo MA. Formation of a Hollow Core in Dendrimers in Solvents. MACROMOL CHEM PHYS 2021. [DOI: 10.1002/macp.202100085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Denis A. Markelov
- Saint Petersburg State University Universitetskaya nab. 7/9 St. Petersburg 199034 Russia
| | - Anna S. Semisalova
- Faculty of Physics and CENIDE University of Duisburg‐Essen Lotharstr. 1 Duisburg 47057 Germany
| | - Mikhail A. Mazo
- Semenov Institute of Chemical Physics Russian Academy of Sciences Kosygina 4 Moscow 119991 Russia
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3
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The branching angle effect on the properties of rigid dendrimers studied by Monte Carlo simulation. J Mol Model 2021; 27:144. [PMID: 33931800 DOI: 10.1007/s00894-021-04767-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 04/20/2021] [Indexed: 10/21/2022]
Abstract
We studied the properties of rigid dendrimers with different branching angles by means of Monte Carlo simulations on a coarse-grained level. It was found that the terminal groups of dendrimers with both rigid and flexible spacers could locate near the center of the molecule. In flexible dendrimers, the wide distribution is attributed to the back folding of flexible spacers, while in rigid dendrimers, it is caused by the branching angle effect that a branch will grow laterally due to the restriction of a non-zero branching angle. It has been established that the branching angle is a key parameter for rigid dendrimers, which can be applied to tune the properties of rigid dendrimers: decreasing branching angle is helpful to obtain dendrimers with a larger size, lower density, and more terminal groups locating at periphery.
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Hammer BAG, Müllen K. Expanding the limits of synthetic macromolecular chemistry through Polyphenylene Dendrimers. JOURNAL OF NANOPARTICLE RESEARCH : AN INTERDISCIPLINARY FORUM FOR NANOSCALE SCIENCE AND TECHNOLOGY 2018; 20:262. [PMID: 30363718 PMCID: PMC6182379 DOI: 10.1007/s11051-018-4364-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/17/2018] [Indexed: 06/08/2023]
Abstract
Polyphenylene dendrimers (PPDs) are a unique class of macromolecules because their backbone is made from twisted benzene repeat units that result in a rigid, shape-persistent architecture as reported by Hammer et al. (Chem Soc Rev 44:4072-4090, 2015) and Hammer and Müllen (Chem Rev 116:2103-210, 2016) These dendrimers can be synthetically tailored at their core, scaffold, and surface to introduce a wide range of chemical functionalities that influence their applications. It is the balance between the macromolecular properties of polyphenylene dendrimers with grandiose synthetic ingenuity that presents a template for the next generation of synthetic dendrimers to achieve complex structures other chemistry fields cannot. This perspective will look at how advances in synthetic chemistry have led to an explosion in the properties of polyphenylene dendrimers from their initial stage, as PPDs that were used as precursors for nanographenes, to next-generation dendrimers for organic electronic devices, sensors for volatile organic compounds (VOCs), nanocarriers for small molecules, and even as complexes with therapeutic drugs and viruses, among others. Ideally, this perspective will illustrate how the evolution of synthetic chemistry has influenced the possible structures and properties of PPDs and how these chemical modifications have opened the door to unprecedented applications.
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Affiliation(s)
- Brenton A. G. Hammer
- Department of Chemistry and Biochemistry, California State University Northridge, 18111 Nordhoff St. 91330, Northridge, CA USA
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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5
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Serenko OA, Kalinin MV, Kuchkina NV, Serkova ES, Strashnov PV, Shifrina ZB. Surface Properties of Low-Generation Polyphenylene Dendrimers. POLYMER SCIENCE SERIES A 2018. [DOI: 10.1134/s0965545x18030094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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6
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Mann G, Twyman LJ, Gale PA. Controlling microenvironments and modifying anion binding selectivities using core functionalised hyperbranched polymers. Chem Commun (Camb) 2016; 52:6131-3. [DOI: 10.1039/c6cc02731h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An isophthalamide anion binding site has been incorporated into hyperbranched polymers resulting in a change in the selectivity of the receptor from chloride to bromide.
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Affiliation(s)
- Georgia Mann
- Department of Chemistry
- University of Sheffield
- Brook Hill
- Sheffield
- UK
| | - Lance J. Twyman
- Department of Chemistry
- University of Sheffield
- Brook Hill
- Sheffield
- UK
| | - Philip A. Gale
- Chemistry
- University of Southampton
- Highfield
- Southampton
- UK
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7
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Brutschy M, Stangenberg R, Beer C, Lubczyk D, Baumgarten M, Müllen K, Waldvogel SR. The Generation Effect: Cavity Accessibility in Dense‐Shell Polyphenylene Dendrimers. Chempluschem 2014. [DOI: 10.1002/cplu.201402298] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Malte Brutschy
- Institute for Organic Chemistry, Johannes Gutenberg‐University Mainz, Duesbergweg 10–14, 55128 Mainz (Germany)
| | - René Stangenberg
- Max‐Planck‐Institute für Polymer Research, Ackermannweg 10, 55128 Mainz (Germany)
| | - Cornelia Beer
- Max‐Planck‐Institute für Polymer Research, Ackermannweg 10, 55128 Mainz (Germany)
| | - Daniel Lubczyk
- Institute for Organic Chemistry, Johannes Gutenberg‐University Mainz, Duesbergweg 10–14, 55128 Mainz (Germany)
| | - Martin Baumgarten
- Max‐Planck‐Institute für Polymer Research, Ackermannweg 10, 55128 Mainz (Germany)
| | - Klaus Müllen
- Max‐Planck‐Institute für Polymer Research, Ackermannweg 10, 55128 Mainz (Germany)
| | - Siegfried R. Waldvogel
- Institute for Organic Chemistry, Johannes Gutenberg‐University Mainz, Duesbergweg 10–14, 55128 Mainz (Germany)
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Chiad K, Grill M, Baumgarten M, Klapper M, Müllen K. Guest Uptake by Rigid Polyphenylene Dendrimers Acting As a Unique Dendritic Box in Solution Proven by Isothermal Calorimetry. Macromolecules 2013. [DOI: 10.1021/ma3024848] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Khalid Chiad
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Matthias Grill
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Martin Baumgarten
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Markus Klapper
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
| | - Klaus Müllen
- Max Planck Institute for Polymer Research, Ackermannweg
10, 55128 Mainz, Germany
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9
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Imaoka T, Inoue N, Yamamoto K. Extended potential-gradient architecture of a phenylazomethine dendrimer. Org Lett 2013; 15:1810-3. [PMID: 23570458 DOI: 10.1021/ol4003493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A dendritic nanoshell based on rigid phenylazomethine units was synthesized up to fifth generation around a zinc porphyrin core. Due to the finely organized sparse architecture, accessibility to the core can be discriminated by the size of the molecules and ionic species. By using this function, the lifetime of the photochemically produced radical ion pair can be extended over 200 times longer along with a good quantum yield.
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Affiliation(s)
- Takane Imaoka
- Chemical Resources Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan
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10
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Albrecht K, Pernites R, Felipe MJ, Advincula RC, Yamamoto K. Patterning Carbazole–Phenylazomethine Dendrimer Films. Macromolecules 2012. [DOI: 10.1021/ma202485h] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Ken Albrecht
- Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsutacho, Midoriku,
Yokohama 226-8503, Japan
| | - Roderick Pernites
- Department of Chemistry and
Department of Chemical Engineering, University of Houston, Houston, Texas 77204-5003, United States
| | - Mary Jane Felipe
- Department of Chemistry and
Department of Chemical Engineering, University of Houston, Houston, Texas 77204-5003, United States
| | - Rigoberto C. Advincula
- Department of Chemistry and
Department of Chemical Engineering, University of Houston, Houston, Texas 77204-5003, United States
| | - Kimihisa Yamamoto
- Chemical Resources Laboratory, Tokyo Institute of Technology, 4259 Nagatsutacho, Midoriku,
Yokohama 226-8503, Japan
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11
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12
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Türp D, Nguyen TTT, Baumgarten M, Müllen K. Uniquely versatile: nano-site defined materials based on polyphenylene dendrimers. NEW J CHEM 2012. [DOI: 10.1039/c1nj20449a] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Kowalczyk RM, Kemp TF, Walker D, Pike KJ, Thomas PA, Kreisel J, Dupree R, Newton ME, Hanna JV, Smith ME. A variable temperature solid-state nuclear magnetic resonance, electron paramagnetic resonance and Raman scattering study of molecular dynamics in ferroelectric fluorides. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:315402. [PMID: 21778562 DOI: 10.1088/0953-8984/23/31/315402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The local nuclear and electronic structures and molecular dynamics of the ferroelectric lattice in selected geometric fluorides (BaMgF(4), BaZnF(4), BaMg(1 - x)Mn(x)F(4) and BaMg(1 - x)Ni(x)F(4); x = 0.001 and 0.005) have been investigated. The (19)F and (25)Mg isotropic chemical shift δ(iso), (25)Mg quadrupolar coupling constants (C(q)) and asymmetry parameters (η) reflect the geometry of the coordination spheres. The zero-field splitting parameters |D| and |E| are consistent with distorted axial symmetry (low temperatures) and nearly rhombic symmetry (high temperatures) of octahedral Mn(2+) coordination. The high resolution of the nuclear magnetic resonance, electron paramagnetic resonance and phonon spectra are consistent with the highly ordered crystallographic structure. Combined multi-technique data evidence the subtle discontinuous changes in the temperature dependences of |D| and |E|, isotropic chemical shifts δ(iso) and signature parameters of Raman bands and suggest a discontinuous structural distortion of the fluoride octahedra. The temperature at which this change occurs depends on the ionic radius of the central ion of the octahedral site and is estimated to be ∼ 300 K for Zn(2+) fluorides and ∼ 240 K for Mg(2+) fluorides. This geometrical distortion modifies the lattice dynamics and originates from the rotation of the fluoride octahedra around a new direction approximately perpendicular to that related to the paraelectric-ferroelectric phase transition.
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Affiliation(s)
- Radoslaw M Kowalczyk
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, UK.
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14
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Schilling CI, Plietzsch O, Nieger M, Muller T, Bräse S. Fourfold Suzuki-Miyaura and Sonogashira Cross-Coupling Reactions on Tetrahedral Methane and Adamantane Derivatives. European J Org Chem 2011. [DOI: 10.1002/ejoc.201001567] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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15
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Imaoka T, Kawana Y, Tsuji M, Yamamoto K. Modulation of the aerobic oxidative polymerization in phenylazomethine dendrimers assembling copper complexes. Chemistry 2010; 16:11003-11. [PMID: 20803586 DOI: 10.1002/chem.201001516] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The aerobic oxidative polymerization of phenol derivatives can provide poly(phenylene oxide)s, which are known as engineering plastics. This oxidation can be carried out with atmospheric oxygen molecules as the oxidizing reagent in the presence of copper complexes as the catalyst; however, stoichiometric or excess amounts of bases are also generally required. By using a phenylazomethine dendrimer complexed with several equivalent amounts of copper chloride, the additive (base)-free polymerization of 2,6-difluorophenol was successful with a very small amount of the catalyst (0.7 mol% of copper for the monomer) because the dendrimer was composed of many Schiff base units, affording a base and catalyst (copper complex) condensed reaction field. The resulting polymer was nearly linear and the molecular weight was very high. When the equimolar amount of the copper complex in one dendrimer molecule was increased, the polymer obtained under this reaction condition was rather branched, resulting in a higher glass transition temperature.
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Affiliation(s)
- Takane Imaoka
- Chemical Resources Laboratory, Tokyo Institute of Technology, 4259, Nagatsuta, Midoriku, Yokohama, 226-8503 Japan
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16
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Yip J, Duhamel J, Bahun GJ, Adronov A. A Study of the Dynamics of the Branch Ends of a Series of Pyrene-Labeled Dendrimers Based on Pyrene Excimer Formation. J Phys Chem B 2010; 114:10254-65. [DOI: 10.1021/jp9102228] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jamie Yip
- Institute for Polymer Research, Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada, and Department of Chemistry and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada
| | - Jean Duhamel
- Institute for Polymer Research, Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada, and Department of Chemistry and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada
| | - Greg J. Bahun
- Institute for Polymer Research, Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada, and Department of Chemistry and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada
| | - Alex Adronov
- Institute for Polymer Research, Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1, Canada, and Department of Chemistry and the Brockhouse Institute for Materials Research, McMaster University, Hamilton, Canada
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17
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Schmelzeisen M, Zhao Y, Klapper M, Müllen K, Kreiter M. Fluorescence enhancement from individual plasmonic gap resonances. ACS NANO 2010; 4:3309-3317. [PMID: 20481545 DOI: 10.1021/nn901655v] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We studied the fluorescence enhancement of a dye-loaded polyphenylene dendrimer in a gap of 2-3 nm between a silver film and single silver particles with an average diameter of 80 nm. This sphere-on-plane geometry provides a controllable plasmonic resonator with a defined dye position. A strong fluorescence signal was seen from all particles, which was at least 1000 times stronger than the signal from the plane dye-coated metal surface. The fluorescence emission profile varied between the particles and showed light emission at higher energies than the free dye, which we assigned to hot luminescence. The maximum fluorescence emission peak shifted along with the scattering maximum of the plasmonic resonance. Two classes of scattering resonators could be distinguished. Up to a significant line-broadening, the response of the "sphere-on-plane"-like cases resembled the theoretical prediction for a perfect sphere-on-plane geometry. Resonators which deviate strongly from this ideal scenario were also found. Electron microscopy did not show significant differences between these two classes, suggesting that the variations in the optical response are due to nanoscale variations of shape and roughness in the gap region. The strong modifications of the dye emission spectrum suggested the presence of physical mechanisms at very small metal/dye separations, which are beyond a simple wavelength-dependent enhancement factor.
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Affiliation(s)
- Marcus Schmelzeisen
- Max-Planck-Institute for Polymer Research, Ackermannweg 10-55128 Mainz, Germany
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18
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Stemmler M, Stefani FD, Bernhardt S, Bauer RE, Kreiter M, Müllen K, Knoll W. One-pot preparation of dendrimer-gold nanoparticle hybrids in a dipolar aprotic solvent. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:12425-12428. [PMID: 19785466 DOI: 10.1021/la902354e] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
We present a simple one-pot, one-step method to obtain stable and nearly monodisperse gold nanoparticles in dipolar aprotic solvents. Novel thiomethyl-functionalized polyphenylene dendrimers are used to control the growth and stabilize the nanoparticles in suspension. The dendrimer functionalized gold nanoparticles have an average size of roughly 10 nm and are stable in suspension for several weeks. The stability in dipolar aprotic solvents and the great functionalization flexibility offered by the dendrimers make these metal/dendrimer hybrid systems promising for applications such as nanophotonics, molecular electronics, and sensing.
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Affiliation(s)
- Marco Stemmler
- Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany
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19
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Albrecht K, Yamamoto K. Dendritic Structure Having a Potential Gradient: New Synthesis and Properties of Carbazole Dendrimers. J Am Chem Soc 2009; 131:2244-51. [DOI: 10.1021/ja807312e] [Citation(s) in RCA: 137] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Ken Albrecht
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
| | - Kimihisa Yamamoto
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
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20
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Markelov DA, Lyulin SV, Gotlib YY, Lyulin AV, Matveev VV, Lahderanta E, Darinskii AA. Orientational mobility and relaxation spectra of dendrimers: Theory and computer simulation. J Chem Phys 2009; 130:044907. [DOI: 10.1063/1.3063116] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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21
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Furer VL, Vandyukova II, Vandyukov AE, Majoral JP, Caminade AM, Kovalenko VI. FTIR and FT-Raman spectra and DFT vibrational analysis of phosphorus-containing dendrons. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 71:1110-1118. [PMID: 18479960 DOI: 10.1016/j.saa.2008.03.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2007] [Revised: 02/29/2008] [Accepted: 03/03/2008] [Indexed: 05/26/2023]
Abstract
FTIR and FT-Raman spectra of four generations of phosphorus-containing dendrons with terminal aldehyde or PCl groups have been recorded and analyzed. Their spectral patterns are determined by the ratio T/R (T, the number of terminal groups; R, the number of repeated units). Bands assigned to the core, repeated units and terminal groups were separated by the difference spectroscopy method. The optimized geometry, frequencies and intensity of IR bands of G(1v) generation dendron with terminal aldehyde groups were obtained by the density functional theory (DFT). It was found that the internal skeleton of molecules exists in a single stable conformation with planar O-C(6)H(4)-CHN-N(CH(3))-P(S) fragments, but terminal groups may adopt the t,g,g- and t,-g,g-rotational isomers. The t,-g,g-conformer is 0.74 kcal/mol less stable compared to the t,g,g-conformer. The bond length and bond angles obtained by DFT show the best agreement with experimental data. Relying on DFT calculations a complete assignment of vibrations is proposed for different parts of the studied dendrons. The calculated frequencies and intensity of IR bands of the t,g,g- and t,-g,g-conformers of G(1v) are found to be in reasonable agreement with the experimental results. The most reactive site in dendron is the core function and vinyl group is preferred for nucleophilic attack. In dendrimer the most reactive are the terminal groups.
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Affiliation(s)
- V L Furer
- Kazan State Architect and Civil Engineering University, Zelenaya 1, Kazan 420043, Russia.
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Andreitchenko EV, Bauer RE, Kreutz C, Baumgarten M, Bargon J, Müllen K. Size and Shape Variation of Polyphenylene Dendrimers through the Heterogeneous Hydrogenation of Embedded Triple Bonds. Macromolecules 2008. [DOI: 10.1021/ma701996j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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24
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Newkome GR, Shreiner CD. Poly(amidoamine), polypropylenimine, and related dendrimers and dendrons possessing different 1→2 branching motifs: An overview of the divergent procedures. POLYMER 2008. [DOI: 10.1016/j.polymer.2007.10.021] [Citation(s) in RCA: 313] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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25
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Pascal RA, Kraml CM, Byrne N, Coughlin FJ. Computational and experimental studies of the conformational reactions of 1,3,5-tris(pentaphenylphenyl)benzene. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.09.021] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Rohmer T, Strauss H, Hughes J, de Groot H, Gärtner W, Schmieder P, Matysik J. 15N MAS NMR studies of cph1 phytochrome: Chromophore dynamics and intramolecular signal transduction. J Phys Chem B 2007; 110:20580-5. [PMID: 17034247 DOI: 10.1021/jp062454+] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Solid-state nuclear magnetic resonance (NMR) is applied for the first time to the photoreceptor phytochrome. The two stable states, Pr and Pfr, of the 59-kDa N-terminal module of the cyanobacterial phytochrome Cph1 from Synechocystis sp. PCC 6803 containing a uniformly 15N-labeled phycocyanobilin cofactor are explored by 15N cross-polarization (CP) magic-angle spinning (MAS) NMR. As recently shown by 15N solution-state NMR using chemical shifts [Strauss, H. M.; Hughes, J.; Schmieder, P. Biochemistry 2005, 44, 8244], all four nitrogens are protonated in both states. CP/MAS NMR provides two additional independent lines of evidence for the protonation of the nitrogens. Apparent loss of mobility during photoactivation, indicated by the decrease of line width, demonstrates strong tension of the entire chromophore in the Pfr state, which is in clear contrast to a more relaxed Pr state. The outer rings (A and D) of the chromophore are significantly affected by the phototransformation, as indicated by both change of chemical shift and line width. On the other hand, on the inner rings (B and C) only minor changes of chemical shifts are detected, providing evidence for a conserved environment during phototransformation. In a mechanical model, the phototransformation is understood in terms of rotations between the A-B and C-D methine bridges, allowing for intramolecular signal transduction to the protein surface by a unit composed of the central rings B and C and its tightly linked protein surroundings during the highly energetic Pfr state.
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Affiliation(s)
- Thierry Rohmer
- Leiden Institute of Chemistry, Gorlaeus Laboratoria, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands
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Yamamoto K, Kawana Y, Tsuji M, Hayashi M, Imaoka T. Additive-Free Synthesis of Poly(phenylene oxide): Aerobic Oxidative Polymerization in a Base-Condensed Dendrimer Capsule. J Am Chem Soc 2007; 129:9256-7. [PMID: 17625859 DOI: 10.1021/ja0727518] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kimihisa Yamamoto
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Japan.
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28
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Harnau L, Rosenfeldt S, Ballauff M. Structure factor and thermodynamics of rigid dendrimers in solution. J Chem Phys 2007; 127:014901. [PMID: 17627363 DOI: 10.1063/1.2750339] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The "polymer reference interaction site model" (PRISM) integral equation theory is used to determine the structure factor of rigid dendrimers in solution. The theory is quite successful in reproducing experimental structure factors for various dendrimer concentrations. In addition, the structure factor at vanishing scattering vector is calculated via the compressibility equation using scaled particle theory and fundamental measure theory. The results as predicted by both theories are systematically smaller than the experimental and PRISM data for platelike dendrimers.
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Affiliation(s)
- L Harnau
- Max-Planck-Institut für Metallforschung, Heisenbergstrasse 3, D-70569 Stuttgart, Germany
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29
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Dhanikula RS, Hildgen P. Conformation and distribution of groups on the surface of amphiphilic polyether-co-polyester dendrimers: Effect of molecular architecture. J Colloid Interface Sci 2007; 311:52-8. [PMID: 17391687 DOI: 10.1016/j.jcis.2007.02.087] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 02/19/2007] [Accepted: 02/22/2007] [Indexed: 11/26/2022]
Abstract
Amphiphilic polyester-co-polyether (PEPE) dendrimers synthesized from poly(ethylene glycol) (PEG) were examined to understand the influence of alterations in the architecture of dendrimers on their conformation at interfaces and distribution of various groups on their surface. Effect of changes in the number of branching points, type of terminal functional groups and generation of dendrimer was primarily evaluated. Dendrimers were deposited on mica by spin coating at 0.1 mg/mL. Tapping mode atomic force microscopy (AFM) was employed for the visualization of dendrimer topographies while, X-ray photoelectron spectroscopy (XPS), AFM phase and force imaging were used as the tools for characterization of their surfaces. Individual dendrimer molecules could be imaged by AFM, which showed that they are round or oval in topography. Dendrimers were also flattened on mica but the extent of flattening differed with the chemical structure; for instance, third generation dendrimers were more flattened than second generation dendrimers whereas, dendrimers with higher number of branches had greater height above the mica surface. Hydrophilic and hydrophobic groups present towards the aerial interface existed in distinct zones rather than being distributed randomly, except in dendrimer with higher number of branches. The percentage of various hydrophobic groups on the surface of dendrimer was enhanced by increase in the number of branches but, was lowered by the presence of hydroxyl groups as the pendant terminal groups. Furthermore, the core of dendrimers was not always located towards the centre, its position was found to be altered by the number of branching points, type of terminal functional groups and the generation of dendrimer.
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Affiliation(s)
- Renu Singh Dhanikula
- Faculty of Pharmacy, University of Montreal, Pavillon Jean-Coutu, C.P. 6128, Succursale Centre-Ville, Montreal, Quebec, H3C 3J7, Canada
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30
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The rotation of pentaphenylphenyl groups and their terminal phenyl groups: a variable-temperature 1H NMR study on an albatrossene and a three-bladed molecular propeller. Tetrahedron Lett 2007. [DOI: 10.1016/j.tetlet.2007.02.079] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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31
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Bernhardt S, Kastler M, Enkelmann V, Baumgarten M, Müllen K. Pyrene as chromophore and electrophore: encapsulation in a rigid polyphenylene shell. Chemistry 2007; 12:6117-28. [PMID: 16847838 DOI: 10.1002/chem.200500999] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Starting from the fourfold ethynyl-substituted chromophore 1,3,6,8-tetraethynylpyrene as core, a series of polyphenylene dendrimers was prepared in high yield by combining divergent and convergent growth methods. The fluorescence quantum yields (Q(f)>0.92) of the encapsulated pyrene chromophore were independent of the size of the polyphenylene shell. Fluorescence quenching studies and temperature-dependent fluorescence spectroscopy were performed to investigate the site isolation of the core. They indicate that a second-generation dendrimer layer is needed to efficiently shield the encapsulated pyrene and prevent aggregate formation. Alkali-metal reduction of the encapsulated pyrene core was carried out to afford the corresponding pyrene radical anions, for which hampered electron transfer to the core was observed with increasing dendrimer generation, which is further proof of the site isolation due to the polyphenylene shell. To improve film formation and solubility of the material, solubilizing alkyl chains were introduced on the periphery of the spherical particles. Furthermore, highly transparent films obtained by a simple drop-casting method showed blue emission mainly from the unaggregated species. The materials presented herein combine high quantum efficiency, good solubility, and improved film-forming properties, which make them possible candidates for several applications in electronic devices.
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Affiliation(s)
- Stefan Bernhardt
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
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32
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Rathgeber S, Monkenbusch M, Hedrick JL, Trollsås M, Gast AP. Starlike dendrimers in solutions: Structural properties and internal dynamics. J Chem Phys 2006; 125:204908. [PMID: 17144741 DOI: 10.1063/1.2364895] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We measured the shape and the internal dynamics of starlike dendrimers under good solvent conditions with small-angle neutron scattering and neutron spin-echo (NSE) spectroscopy, respectively. Architectural parameters such as the spacer length and generation were varied in a systematic manner. Structural changes occurring in the dendrimers as a function of these parameters are discussed, i.e., in terms of the fractal dimension and deviations of the radius of gyration from the Gaussian value. A first cumulant evaluation of the NSE spectra for each scattering vector q separately yields the length scale dependent relaxation rates. We observe a local minimum in the normalized relaxation rates Omega(q)q(3) on length scales corresponding to the overall dendrimer dimension. The dynamics is discussed within a Rouse-Zimm approach generalized to the case of starlike dendrimers of arbitrary geometry. The model allows an identification of the modes contributing to the relaxation of the dendrimer in the q and time range of the NSE experiment. The local minimum is due to collective breathing motions of (parts of) the dendrons relative to each other. Shape fluctuations are not observed.
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Affiliation(s)
- Silke Rathgeber
- Max-Planck Institut für Polymerforschung, Polymer Physik, D-55128 Mainz, Germany.
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33
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Enoki O, Katoh H, Yamamoto K. Synthesis and properties of a novel phenylazomethine dendrimer with a tetraphenylmethane core. Org Lett 2006; 8:569-71. [PMID: 16468713 DOI: 10.1021/ol052673y] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[structure: see text] A new type of phenylazomethine dendrimer with a tetraphenylmethane core was synthesized by a convergent method. The properties of the dendrimer were confirmed by thermal, rheological, TEM, and AFM measurements. A stepwise radial complexation was clearly observed with SnCl(2).
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Affiliation(s)
- Osamu Enoki
- Department of Chemistry, Faculty of Science and Technology, Keio University, Yokohama 223-8522, Japan
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34
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Komber H, Stumpe K, Voit B. NMR Study of Hyperbranched Polyphenylenes from the AB2, (AB2 + AB) and (A2 + B3) Methods. MACROMOL CHEM PHYS 2006. [DOI: 10.1002/macp.200600351] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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35
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Imaoka T, Tanaka R, Yamamoto K. Investigation of a Molecular Morphology Effect on Polyphenylazomethine Dendrimers; Physical Properties and Metal-Assembling Processes. Chemistry 2006; 12:7328-36. [PMID: 16888740 DOI: 10.1002/chem.200600511] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A series of novel dendritic polyphenylazomethines (DPA) with asymmetric morphologies was synthesized. Their physical properties, such as encapsulating effect, molecular dynamics, and metal assembly, are strongly dependent on the entire conformation of the molecules. The most important property is layer-by-layer metal assembly in the dendrimer structure from the core to the outside. Bis- and tris-substituted DPAs of the fourth generation also act as frameworks for stepwise assembly of a metal component (SnCl2), like the fully substituted symmetric DPA. However, extensive investigation of metal assembly in specific DPAs revealed that they do not follow the stepwise process. The molecular density calculated from the experimental hydrodynamic volume indicated that bis- and tris-substituted DPAs with asymmetric morphology still retain a free space similar to that of fully substituted symmetric DPA. The monosubstituted DPA, however, displayed a slightly higher density (smaller space) than the other DPAs. The experimental results suggest a bent conformation of the dendrimer in which the core moiety is folded into the dendron structure. In addition, the molecular dynamics were probed by means of the 1H NMR signals of the porphyrin core. It was demonstrated that the conformation is not fixed at room temperature in solvated DPAs, especially in monosubstituted DPA. A similar observation was for the smaller DPAs (third generations) with asymmetric morphologies. These dendrimers do not follow the stepwise complexation process. The structures of bis- and tris-substituted dendrimers which accurately follow the stepwise process are fixed. These observations provide a new insight into the finely controlled metal-assembly chemistry of dendritic macromolecules, and a rigid and fixed conformation is one of important factors for their unique properties.
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Affiliation(s)
- Takane Imaoka
- Department of Chemistry, Keio University, 223-8522 Yokohama, Japan
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36
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Wickramasinghe NP, Ishii Y. Sensitivity enhancement, assignment, and distance measurement in 13C solid-state NMR spectroscopy for paramagnetic systems under fast magic angle spinning. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2006; 181:233-43. [PMID: 16750405 DOI: 10.1016/j.jmr.2006.05.008] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2006] [Revised: 05/11/2006] [Accepted: 05/11/2006] [Indexed: 05/10/2023]
Abstract
Despite success of previous studies, high-resolution solid-state NMR (SSNMR) of paramagnetic systems has been still largely unexplored because of limited sensitivity/resolution and difficulty in assignment due to large paramagnetic shifts. Recently, we demonstrated that an approach using very-fast magic angle spinning (VFMAS; spinning speed 20kHz) enhances resolution/sensitivity in (13)C SSNMR for paramagnetic complexes [Y. Ishii, S. Chimon, N.P. Wickramasinghe, A new approach in 1D and 2D (13)C high resolution solid-state NMR spectroscopy of paramagnetic organometallic complexes by very fast magic-angle spinning, J. Am. Chem. Soc. 125 (2003) 3438-3439]. In this study, we present a new strategy for sensitivity enhancement, signal assignment, and distance measurement in (13)C SSNMR under VFMAS for unlabeled paramagnetic complexes using recoupling-based polarization transfer. As a robust alternative of cross-polarization (CP), rapid application of recoupling-based polarization transfer under VFMAS is proposed. In the present approach, a dipolar-based analog of INEPT (dipolar INEPT) methods is used for polarization transfer and a (13)C signal is observed under VFMAS without (1)H decoupling. The resulting low duty factor permits rapid signal accumulation without probe arcing at recycle times ( approximately 3 ms/scan) matched to short (1)H T(1) values of small paramagnetic systems ( approximately 1 ms). Experiments on Cu(dl-Ala)(2) showed that the fast repetition approach under VFMAS provided sensitivity enhancement by a factor of 8-66 for a given sample, compared with the (13)C MAS spectrum under moderate MAS at 5kHz. The applicability of this approach was also demonstrated for a more challenging system, Mn(acac)(3), for which (13)C and (1)H paramagnetic shift dispersions reach 1500 and 700 ppm, respectively. It was shown that effective-evolution-time dependence of transferred signals in dipolar INEPT permitted one to distinguish (13)CH, (13)CH(2), (13)CH(3), (13)CO2- groups in 1D experiments for Cu(DL-Ala)(2) and Cu(Gly)(2). Applications of this technique to 2D (13)C/(1)H correlation NMR under VFMAS yielded reliable assignments of (1)H resonances as well as (13)C resonances for Cu(DL-Ala)(2) and Mn(acac)(3). Quantitative analysis of cross-peak intensities in 2D (13)C/(1)H correlation NMR spectra of Cu(DL-Ala)(2) provided distance information between non-bonded (13)C-(1)H pairs in the paramagnetic system.
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37
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Carbone P, Calabretta A, Di Stefano M, Negri F, Müllen K. Shape Persistence and Bistability of Planar Three-Fold Core Polyphenylene Dendrimers: A Molecular Dynamics Study. J Phys Chem A 2006; 110:2214-24. [PMID: 16466258 DOI: 10.1021/jp0551420] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present an atomistic molecular dynamics investigation of the structural time evolution of isolated polyphenylene dendrimers, carbon based dendrimers with a planar core formed by a 1,3,5 trisubstituted benzene ring. Simulations are carried out at low (80 K) and room temperature. A general classification of the conformations (core conformations) assumed by the three dendrimer branches with respect to the planar core is presented. It is found that out of the six possible core conformations only four are stable, the remaining two being unstable for steric reasons. For second generation dendrimers, two of the four accessible core conformations are associated with an open arrangement of the three branches attached to the planar 3-fold core of the dendrimer, whereas the remaining two are associated with a collapsed arrangement of two branches. At low temperature the initial conformation is generally conserved whereas at room temperature jumps among the four possible core conformations are observed in the nanosecond time range. For second generation dendrimers the core conformation jumps are associated with an oscillation between two global shape states: open and collapsed. The computed bistability of the global shape suggests additional possible functional uses for some of these carbon based dendrimers.
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Affiliation(s)
- Paola Carbone
- Dipartimento di Chimica G. Ciamician, Università di Bologna, Via Francesco Selmi 2, 40126 Bologna, Italy
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38
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Andreitchenko EV, Clark CG, Bauer RE, Lieser G, Müllen K. Pushing the Synthetic Limit: Polyphenylene Dendrimers with “Exploded” Branching Units—22-nm-Diameter, Monodisperse, Stiff Macromolecules. Angew Chem Int Ed Engl 2005; 44:6348-54. [PMID: 16145701 DOI: 10.1002/anie.200501368] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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39
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Andreitchenko EV, Clark CG, Bauer RE, Lieser G, Müllen K. Pushing the Synthetic Limit: Polyphenylene Dendrimers with “Exploded” Branching Units—22-nm-Diameter, Monodisperse, Stiff Macromolecules. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200501368] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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40
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Bernhardt S, Baumgarten M, Wagner M, Müllen K. Multiple Functionalization of Benzophenones Inside Polyphenylene Dendrimers − Toward Entrapped Ions and Radicals. J Am Chem Soc 2005; 127:12392-9. [PMID: 16131221 DOI: 10.1021/ja052856f] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polyphenylene dendrimers possessing a defined number of keto groups in the dendritic scaffold have been synthesized by using a benzophenone-functionalized tetraphenylcyclopentadienone branching unit. A postsynthetic functionalization of the polyphenylene backbone was achieved by reacting the entrapped keto groups with organolithium reagents yielding monodisperse alcohol products. To investigate the accessibility and reactivity of the embedded groups, many functions of different size and nature, for example, the chromophore pyrene, were introduced. Moreover, suitable precursors for the synthesis of dendrimer entrapped species, trityl cations, trityl radicals, and ketyl radical anions, were obtained. To gain insight into the structure of these newly functionalized dendrimers, UV/vis, EPR, and NMR measurements have been performed. They showed a delocalization of the charge/spin into the polyphenylene dendritic arms leading to a stabilization of the ions/radicals. Remarkably, for the ketyl radicals, EPR measurements indicated the occurrence of intermolecular metal-bridged biradicals. They suggest the existence of a dendritic radical network of the dendrimers themselves.
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Affiliation(s)
- Stefan Bernhardt
- Max-Planck-Institut für Polymerforschung, Ackermannweg 10, D-55128 Mainz, Germany
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41
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Fischbach I, Spiess HW, Saalwächter K, Goward GR. Solid State NMR Spectroscopic Investigations of Model Compounds for Imidazole-Based Proton Conductors. J Phys Chem B 2004. [DOI: 10.1021/jp046848h] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ingrid Fischbach
- BASF AG, Polymer Research, Department of Polymer Physics, 67056 Ludwigshafen, Germany
| | | | - Kay Saalwächter
- Institut für Makromolekulare Chemie, Universität Freiburg, Stefan-Meier Str. 31, D-79104 Freiburg
| | - Gillian R. Goward
- Department of Chemistry, McMaster University, 1280 Main St. W., Hamilton, ON, L8S 4M1 Canada
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42
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Spiess HW. Advanced solid-state nuclear magnetic resonance for polymer science. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/pola.20365] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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43
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Malveau C, Baille WE, Zhu XX, Ford WT. Molecular dynamics of hydrophilic poly(propylene imine) dendrimers in aqueous solutions by1H NMR relaxation. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/polb.10584] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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44
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Klein Wolterink J, van Male J, Daoud M, Borisov OV. Starburst Polyelectrolytes: Scaling and Self-Consistent-Field Theory. Macromolecules 2003. [DOI: 10.1021/ma030187p] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. Klein Wolterink
- Wageningen University, Laboratory for Physical Chemistry, and Colloid Science, 6703 HB Wageningen, The Netherlands; Service de Physique de l'Etat Condensé, CE-Saclay, 91191 Gif sur Yvette, France; Institute of Macromolecular Compounds of the Russian Academy of Sciences, 199004, St. Petersburg, Russia; and LRMP/UMR 5067, Helioparc Pau-Pyrenees, 64053 Pau, France
| | - J. van Male
- Wageningen University, Laboratory for Physical Chemistry, and Colloid Science, 6703 HB Wageningen, The Netherlands; Service de Physique de l'Etat Condensé, CE-Saclay, 91191 Gif sur Yvette, France; Institute of Macromolecular Compounds of the Russian Academy of Sciences, 199004, St. Petersburg, Russia; and LRMP/UMR 5067, Helioparc Pau-Pyrenees, 64053 Pau, France
| | - M. Daoud
- Wageningen University, Laboratory for Physical Chemistry, and Colloid Science, 6703 HB Wageningen, The Netherlands; Service de Physique de l'Etat Condensé, CE-Saclay, 91191 Gif sur Yvette, France; Institute of Macromolecular Compounds of the Russian Academy of Sciences, 199004, St. Petersburg, Russia; and LRMP/UMR 5067, Helioparc Pau-Pyrenees, 64053 Pau, France
| | - O. V. Borisov
- Wageningen University, Laboratory for Physical Chemistry, and Colloid Science, 6703 HB Wageningen, The Netherlands; Service de Physique de l'Etat Condensé, CE-Saclay, 91191 Gif sur Yvette, France; Institute of Macromolecular Compounds of the Russian Academy of Sciences, 199004, St. Petersburg, Russia; and LRMP/UMR 5067, Helioparc Pau-Pyrenees, 64053 Pau, France
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