1
|
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
| |
Collapse
|
2
|
Eckert PA, Kubarych KJ. Solvent Quality Controls Macromolecular Structural Dynamics of a Dendrimeric Hydrogenase Model. J Phys Chem B 2018; 122:12154-12163. [PMID: 30427195 DOI: 10.1021/acs.jpcb.8b07259] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
We report a spectroscopic investigation of the ultrafast dynamics of the second-generation poly(aryl ether) dendritic hydrogenase model using two-dimensional infrared (2D-IR) spectroscopy to probe the metal carbonyl vibrations of the dendrimer and a reference small molecule, [Fe(μ-S)(CO)3]2. We find that the structural dynamics of the dendrimer are reflected in a slow phase of the spectral diffusion, which is absent from [Fe(μ-S)(CO)3]2, and we relate the slow phase to the quality of the solvent for poly(aryl ether) dendrimers. We observe a solvent-dependent modulation of the initial phase of vibrational relaxation of the carbonyl groups, which we attribute to an inhibition of solvent assistance in the intramolecular vibrational redistribution process for the dendrimer. There is also a clear solvent dependence of the vibrational frequencies of both the dendrimer and [Fe(μ-S)(CO)3]2. Our data represent the first 2D-IR study of a dendritic complex and provide insight into the solvent dependence of molecular conformation in solution and the ultrafast dynamics of moderately sized, conformationally mobile compounds.
Collapse
Affiliation(s)
- Peter A Eckert
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 49109 , United States
| | - Kevin J Kubarych
- Department of Chemistry , University of Michigan , 930 N. University Avenue , Ann Arbor , Michigan 49109 , United States
| |
Collapse
|
3
|
Zhang Y, Valiya Parambathu A, Chapman WG. Density functional study of dendrimer molecules in solvents of varying quality. J Chem Phys 2018; 149:064904. [PMID: 30111128 DOI: 10.1063/1.5035423] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Modified inhomogeneous statistical associating fluid theory (iSAFT) density functional theory is extended to dendrimer molecules in solvents of varying quality. The detailed structures of isolated dendrimers in implicit solvent are calculated and have a semi-quantitative agreement with simulation results available in the literature. The dendrimers form dense-core structures under all conditions, while their radius of gyration follows different scaling laws. Factors that affect the quality of the solvent are systematically studied in the explicit solvent case. It is found that the solvent size, density, chemical affinity and temperature all play a role in determining a solvent to be good or poor. New molecular dynamics simulations are performed to validate the iSAFT results. Our results provide insight into the phase behavior of dendrimer solutions as well as guidance in practical applications.
Collapse
Affiliation(s)
- Yuchong Zhang
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, USA
| | - Arjun Valiya Parambathu
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, USA
| | - Walter G Chapman
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, USA
| |
Collapse
|
4
|
Chen C, Tang P, Qiu F, Shi AC. Density Functional Study for Homodendrimers and Amphiphilic Dendrimers. J Phys Chem B 2016; 120:5553-63. [DOI: 10.1021/acs.jpcb.6b03005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Cangyi Chen
- The
State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory
of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Ping Tang
- The
State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory
of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Feng Qiu
- The
State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory
of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - An-Chang Shi
- Department
of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada L8S 4M1
| |
Collapse
|
5
|
Kitamatsu M, Kitabatake M, Noutoshi Y, Ohtsuki T. Synthesis and properties of peptide dendrimers containing fluorescent and branched amino acids. Biopolymers 2016; 100:64-70. [PMID: 23335168 DOI: 10.1002/bip.22175] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Revised: 10/03/2012] [Accepted: 10/08/2012] [Indexed: 11/10/2022]
Abstract
In this report, we describe dendritic peptides possessing central fluorescent amino acids with adjacent branched amino acids. These fluorescent-peptide dendrimers were prepared using (9-fluorenyl)methoxycarbonyl (Fmoc)-based solid-phase peptide synthesis and Fmoc-derivative fluorescent and branched amino acids. The branched amino acids featured multiple carboxylic acids in their side chains, making the fluorescent-peptide dendrimers highly water-soluble compared with the analogous peptides containing the fluorescent amino acids only. The branched amino acid units also improved the fluorescence intensity of the dendrimers. Based on high-pressure liquid chromatography and fluorescence spectroscopy results, we determined that the fluorescent groups were located in the core and that the carboxylic acids were located on the surface of the dendrimers. Fluorescence resonance energy transfer was achieved among the three proximal fluorescent groups in one of the fabricated fluorescent-peptide dendrimers.
Collapse
Affiliation(s)
- Mizuki Kitamatsu
- Department of Applied Chemistry, Kinki University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan. kitamatu@ apch.kindai.ac.jp
| | | | | | | |
Collapse
|
6
|
Ortiz AM, Sánchez-Méndez A, de Jesús E, Flores JC, Gómez-Sal P, Mendicuti F. Poly(benzyl ether) Dendrimers Functionalized at the Core with Palladium Bis(N-Heterocyclic Carbene) Complexes as Catalysts for the Heck Coupling Reaction. Inorg Chem 2016; 55:1304-14. [DOI: 10.1021/acs.inorgchem.5b02629] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Alba M. Ortiz
- Departamento de Química Orgánica
y Química Inorgánica, Universidad de Alcalá, Edificio de Farmacia, Campus Universitario, E28871 Alcalá
de Henares, Madrid, Spain
| | - Alberto Sánchez-Méndez
- Departamento de Química Orgánica
y Química Inorgánica, Universidad de Alcalá, Edificio de Farmacia, Campus Universitario, E28871 Alcalá
de Henares, Madrid, Spain
| | - Ernesto de Jesús
- Departamento de Química Orgánica
y Química Inorgánica, Universidad de Alcalá, Edificio de Farmacia, Campus Universitario, E28871 Alcalá
de Henares, Madrid, Spain
| | - Juan C. Flores
- Departamento de Química Orgánica
y Química Inorgánica, Universidad de Alcalá, Edificio de Farmacia, Campus Universitario, E28871 Alcalá
de Henares, Madrid, Spain
| | - Pilar Gómez-Sal
- Departamento de Química Orgánica
y Química Inorgánica, Universidad de Alcalá, Edificio de Farmacia, Campus Universitario, E28871 Alcalá
de Henares, Madrid, Spain
| | - Francisco Mendicuti
- Departamento de Química Analítica, Química Física e Ingeniería Química, Universidad de Alcalá, E28871 Alcalá de Henares, Madrid, Spain
| |
Collapse
|
7
|
Zeng Y, Li P, Liu X, Yu T, Chen J, Yang G, Li Y. A “breathing” dendritic molecule—conformational fluctuation induced by external stimuli. Polym Chem 2014. [DOI: 10.1039/c4py00714j] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
8
|
Dendritic effects on photophysical and fluorescence properties of coumarin functionalized dendrigraft polybutadiene. POLYMER 2014. [DOI: 10.1016/j.polymer.2014.01.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
9
|
Pinto LF, Correa J, Martin-Pastor M, Riguera R, Fernandez-Megia E. The Dynamics of Dendrimers by NMR Relaxation: Interpretation Pitfalls. J Am Chem Soc 2013; 135:1972-7. [DOI: 10.1021/ja311908n] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luiz F. Pinto
- Department of Organic Chemistry
and Center for Research in Biological Chemistry and Molecular Materials
(CIQUS), University of Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Juan Correa
- Department of Organic Chemistry
and Center for Research in Biological Chemistry and Molecular Materials
(CIQUS), University of Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Manuel Martin-Pastor
- Unidade de Resonancia Magnética,
RIAIDT, CACTUS, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Ricardo Riguera
- Department of Organic Chemistry
and Center for Research in Biological Chemistry and Molecular Materials
(CIQUS), University of Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain
| | - Eduardo Fernandez-Megia
- Department of Organic Chemistry
and Center for Research in Biological Chemistry and Molecular Materials
(CIQUS), University of Santiago de Compostela, Jenaro de la Fuente s/n, 15782 Santiago de Compostela, Spain
| |
Collapse
|
10
|
Affiliation(s)
- Jaroslaw T. Bosko
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - J. Ravi Prakash
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
| |
Collapse
|
11
|
Aumanen J, Teobaldi G, Zerbetto F, Korppi-Tommola J. The effect of temperature on the internal dynamics of dansylated POPAM dendrimers. RSC Adv 2011. [DOI: 10.1039/c1ra00625h] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
|
12
|
Sánchez-Méndez A, de Jesús E, Flores JC, Gómez-Sal P. Fréchet-Type Pallado-Dendrimers Containing Bis(pyrazolyl)methane Ligands. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900869] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
13
|
Javor S, Reymond JL. Molecular Dynamics and Docking Studies of Single Site Esterase Peptide Dendrimers. J Org Chem 2009; 74:3665-74. [DOI: 10.1021/jo802743c] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Sacha Javor
- Department of Chemistry and Biochemistry, University of Berne, Freiestrasse 3, CH-3012, Berne, Switzerland
| | - Jean-Louis Reymond
- Department of Chemistry and Biochemistry, University of Berne, Freiestrasse 3, CH-3012, Berne, Switzerland
| |
Collapse
|
14
|
Martini G, Ciani L. Electron spin resonance spectroscopy in drug delivery. Phys Chem Chem Phys 2009; 11:211-54. [DOI: 10.1039/b808263d] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
|
15
|
Yang J, Cho S, Yoo H, Park J, Li WS, Aida T, Kim D. Control of Molecular Structures and Photophysical Properties of Zinc(II) Porphyrin Dendrimers Using Bidentate Guests: Utilization of Flexible Dendrimer Structures as a Controllable Mold. J Phys Chem A 2008; 112:6869-76. [DOI: 10.1021/jp800337y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jaesung Yang
- Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea, ERATO-SORST Nanospace Project, Japan Science and Technology Agency (JST), National Museum of Emerging Science and Innovation, 2-41 Aomi, Koto-ku, Tokyo 135-0064, Japan, and Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Sung Cho
- Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea, ERATO-SORST Nanospace Project, Japan Science and Technology Agency (JST), National Museum of Emerging Science and Innovation, 2-41 Aomi, Koto-ku, Tokyo 135-0064, Japan, and Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Hyejin Yoo
- Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea, ERATO-SORST Nanospace Project, Japan Science and Technology Agency (JST), National Museum of Emerging Science and Innovation, 2-41 Aomi, Koto-ku, Tokyo 135-0064, Japan, and Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Jaehong Park
- Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea, ERATO-SORST Nanospace Project, Japan Science and Technology Agency (JST), National Museum of Emerging Science and Innovation, 2-41 Aomi, Koto-ku, Tokyo 135-0064, Japan, and Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Wei-Shi Li
- Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea, ERATO-SORST Nanospace Project, Japan Science and Technology Agency (JST), National Museum of Emerging Science and Innovation, 2-41 Aomi, Koto-ku, Tokyo 135-0064, Japan, and Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Takuzo Aida
- Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea, ERATO-SORST Nanospace Project, Japan Science and Technology Agency (JST), National Museum of Emerging Science and Innovation, 2-41 Aomi, Koto-ku, Tokyo 135-0064, Japan, and Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Dongho Kim
- Center for Ultrafast Optical Characteristics Control and Department of Chemistry, Yonsei University, Seoul 120-749, Korea, ERATO-SORST Nanospace Project, Japan Science and Technology Agency (JST), National Museum of Emerging Science and Innovation, 2-41 Aomi, Koto-ku, Tokyo 135-0064, Japan, and Department of Chemistry and Biotechnology, School of Engineering, and Center for NanoBio Integration, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| |
Collapse
|
16
|
Moreno KX, Simanek EE. Conformational Analysis of Triazine Dendrimers: Using NMR Spectroscopy To Probe the Choreography of a Dendrimer's Dance. Macromolecules 2008; 41:4108-4114. [PMID: 19946610 DOI: 10.1021/ma702143f] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
One-dimensional (1D) and two-dimensional (2D) NMR studies are used to probe the conformation of a melamine dendrimer bearing unique NMR signals from the core to the periphery. Four conceptual anchors for dendrimer conformation emerge from these experiments. First, changes in isomer populations observed by (1)H NMR reveal the onset of globular structure. Second, NOE complexity emerges with globular structure: variable temperature NOESY studies show that the peripheral groups, BOC-protected aliphatic amines, fold back into the globular core of the macromolecule at 75 degrees C in DMSO-d(6). Third, variable temperature coefficients measured for NH protons suggest that solvent is largely excluded from the interior of the dendrimer: the carbamate NH groups of the periphery are most sensitive to temperature while the NHs nearest the core show little temperature dependence. Conformation is influenced by solvent choice: backfolding is observed in DMSO-d(6), but not in either CDCl(3) or CD(3)OD. Finally, relaxation studies show that peripheral groups are more dynamic than groups at the core. These anchors consolidate observations made by many groups on disparate systems within a common architecture.
Collapse
Affiliation(s)
- Karlos X Moreno
- Department of Chemistry, Texas A&M University, MS 3255, College Station, Texas 77843
| | | |
Collapse
|
17
|
Matos MS, Hofkens J, Gehlen MH. Static and Dynamic Bimolecular Fluorescence Quenching of Porphyrin Dendrimers in Solution. J Fluoresc 2008; 18:821-6. [DOI: 10.1007/s10895-007-0309-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2007] [Accepted: 12/28/2007] [Indexed: 11/28/2022]
|
18
|
Li YY, Han L, Chen J, Zheng S, Zen Y, Li Y, Li S, Yang G. Study on the Extent of Folding Back Conformation in Poly(aryl ether) Dendrimers by Intramolecular Electron Transfer and Exciplex Formation. Macromolecules 2007. [DOI: 10.1021/ma071901w] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
19
|
Amore A, van Heerbeek R, Zeep N, van Esch J, Reek JNH, Hiemstra H, van Maarseveen JH. Carbosilane dendrimeric carbodiimides: site isolation as a lactamization tool. J Org Chem 2007; 71:1851-60. [PMID: 16496969 DOI: 10.1021/jo052027c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The convergent syntheses of three generations of carbosilane dendrimeric carbodiimides are described. The wedge-type building blocks were synthesized in a divergent way, starting from allyl chloride and a repetitive sequence of hydrosilylation with HSiCl3 and a Grignard reaction with allylmagnesium bromide. Hydrogenation of the terminal double bonds led to inert and stable wedges. The chloride substituent at the focal point was transformed into several functional groups that eventually led to dendrimeric structures with a carbodiimide core. The extent of the site isolation effect of the dendrimers was studied with dilution experiments monitored by FT-IR spectroscopy on the corresponding dendrimeric ureas. These studies showed that only the first generation self-aggregates via hydrogen bonding, while the second and the third do not, implying isolation of core-bound moieties. The dendrimeric carbodiimides mediated lactamization reactions to obtain homodiketopiperazines.
Collapse
Affiliation(s)
- Alessia Amore
- Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 129, 1018 WS Amsterdam, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
20
|
Brauge L, Vériot G, Franc G, Deloncle R, Caminade AM, Majoral JP. Synthesis of phosphorus dendrimers bearing chromophoric end groups: toward organic blue light-emitting diodes. Tetrahedron 2006. [DOI: 10.1016/j.tet.2006.09.093] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
21
|
Hietala S, Nyström A, Tenhu H, Hult A. Solution properties of dendronized poly(hydroxy ethyl methacrylate) polymers. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/pola.21471] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
22
|
Boas U, Christensen JB, Heegaard PMH. Dendrimers: design, synthesis and chemical properties. ACTA ACUST UNITED AC 2006. [DOI: 10.1039/b611813p] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
23
|
Brocorens P, Lazzaroni R, Brédas JL. The Conformation of Amine- and Amide-Terminated Poly(Propylene Imine) Dendrimers as Investigated by Molecular Simulation Methods. J Phys Chem B 2005; 109:19897-907. [PMID: 16853573 DOI: 10.1021/jp0520493] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The parameters that influence the conformation of poly(propylene imine) dendrimers were investigated by molecular simulations using molecular mechanics and simulated annealing methods. Dendrimers with two types of peripheral units able to communicate via hydrogen bonding-amine and amide moieties-were considered in order to study the role that secondary interactions among the end groups have in the spatial organization of the dendritic branches. Radial atomic density profiles and radial atomic probability distributions were used to extract global properties, such as the degree of packing of the branches, the distribution of the monomers throughout the molecular volume, and the extent and characteristics of the surface region. Information was also obtained about the nature, location, and extent of formation of the hydrogen bonds, as well as their evolution with dendrimer generation and their assembly into networks. The analyses were supported by a detailed investigation of the first two generations, with an emphasis on the relationship between hydrogen bonding and the compactness and stability of the molecules; this allowed us to account for the generational evolution of hydrogen bonding that is experimentally observed in several poly(propylene imine) dendrimers.
Collapse
Affiliation(s)
- Patrick Brocorens
- Service de Chimie des Matériaux Nouveaux, Université de Mons-Hainaut, Place du Parc, 20, B-7000 Mons (Belgium)
| | | | | |
Collapse
|
24
|
Cotlet M, Vosch T, Habuchi S, Weil T, Müllen K, Hofkens J, De Schryver F. Probing Intramolecular Förster Resonance Energy Transfer in a Naphthaleneimide−Peryleneimide−Terrylenediimide-Based Dendrimer by Ensemble and Single-Molecule Fluorescence Spectroscopy. J Am Chem Soc 2005; 127:9760-8. [PMID: 15998080 DOI: 10.1021/ja042656o] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report on the ensemble and single-molecule (SM) dynamics of Förster resonance energy transfer (FRET) in a multichromophoric rigid polyphenylenic dendrimer (triad) with spectrally different rylene chromophores featuring distinct absorption and emission spectra which cover the whole visible spectral range: a terrylenediimide (TDI) core, four perylenemonoimides (PMIs) attached at the scaffold, and eight naphthalenemonoimides (NMIs) at the rim. For FRET from PMI to TDI taking place with an efficiency of 99.5%, single triad molecules optically excited at 490 nm show fluorescence exclusively from the TDI side in the beginning of their emission. On 360-nm excitation, NMI chromophores transfer their excitation energy either directly or in a stepwise fashion to the core TDI, the latter case involving scaffold-substituted PMIs as intermediate acceptors. Indeed, SM experiments on 360-nm excitation evidence highly efficient FRET from NMI chromophores to the TDI core since individual triad molecules show fluorescence exclusively either from TDI or from an intermediate (oxidized) species but never from PMI. Because PMI and TDI are chromophores with high fluorescence quantum yields and high resistance to photobleaching compared to NMI, 360-nm excitation of a single triad molecule leads to bleaching of NMI chromophores with no chance for PMI to be observed. The spatial positioning and the spectral properties of the chosen rylene chromophores make this multichromophoric system an efficient light collector, able to capture light over the whole visible spectral range and to transfer it finally to the core TDI, the latter releasing it as red fluorescence.
Collapse
Affiliation(s)
- Mircea Cotlet
- Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200 F, Heverlee B-3001, Belgium
| | | | | | | | | | | | | |
Collapse
|
25
|
Chen YC, Wu TF, Jiang L, Deng JG, Liu H, Zhu J, Jiang YZ. Synthesis of dendritic catalysts and application in asymmetric transfer hydrogenation. J Org Chem 2005; 70:1006-10. [PMID: 15675861 DOI: 10.1021/jo048317v] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Frechet-type core-functionalized chiral diamine-based dendritic ligands and hybrid dendritic ligands condensed from polyether wedge and Newkome-type poly(ether-amide) supported multiple ligands were designed and synthesized. The solubility of hybrid dendrimers was found to be finely controlled by the polyether dendron. The catalytic efficiency and recovery use of dendritic ruthenium complexes were compared in the transfer hydrogenation of acetophenone. The core-functionalized dendritic catalysts demonstrated much better recyclability, which verified the stabilizing effects of the bulky polyether wedge on the catalytically active complex. Moreover, the dendritic catalysts were applied in the asymmetric transfer hydrogenation of ketones, enones, imine, and activated olefin, and moderate to excellent enantioselectivitiy was achieved comparable to that of monomeric catalysts.
Collapse
Affiliation(s)
- Ying-Chun Chen
- Key Laboratory of Asymmetric Synthesis & Chirotechnology of Sichuan Province and Union Laboratory of Asymmetric Synthesis, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China
| | | | | | | | | | | | | |
Collapse
|
26
|
Verheijen W, Hofkens J, Metten B, Vercammen J, Shukla R, Smet M, Dehaen W, Engelborghs Y, De Schryver F. The Photo Physical Properties of Dendrimers Containing 1,4-Dioxo-3,6-Diphenylpyrrolo[3,4-c]pyrrole (DPP) as a Core. MACROMOL CHEM PHYS 2005. [DOI: 10.1002/macp.200400144] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
27
|
Bourrier O, Butlin J, Hourani R, Kakkar AK. Aggregation of 3,5-dihydroxybenzyl alcohol based dendrimers and hyperbranched polymers, and encapsulation of DR1 in such dendritic aggregates. Inorganica Chim Acta 2004. [DOI: 10.1016/j.ica.2004.02.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
28
|
Giupponi G, Buzza DMA. Monte Carlo simulation of dendrimers in variable solvent quality. J Chem Phys 2004; 120:10290-8. [PMID: 15268054 DOI: 10.1063/1.1714829] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We study via lattice Monte Carlo simulation and Flory theory the properties of g=1-6 dendrimers in variable solvent quality. For all the generations studied, we find that the radius of gyration R(g) collapses significantly (factor of 2) going from athermal to extreme poor solvent conditions, indicating that varying solvent quality is an effective means of controlling dendrimer size. We also find that in athermal, theta, and extreme poor solvent conditions, the radius of gyration of dendrimers scales with the total number of monomers roughly as R(g) approximately N(1/3). However, a more careful analysis shows that in athermal and theta solvents, there is, in fact, a small but systematic deviation of R(g) from R(g) approximately N(1/3) scaling and the simulation data is described better by the Flory theory prediction of R(g) approximately N(1/5)[(g+1)m](2/5) in athermal solvents and R(g) approximately N(1/4)[(g+1)m](1/4) in theta solvents. We also find for our simulation data that stronger deviations from constant density scaling are possible, with scaling behavior as shallow as R(g) approximately N(0.26) possible for solvent conditions in between theta and the completely collapsed state. It is evident therefore that dendrimers do not obey (or even approximately obey) R(g) approximately N(1/3) scaling under all solvent conditions. Under all solvent conditions, we find that the intramolecular density is dense corelike (i.e., the density maximum is in the interior of the dendrimer) and terminal groups are delocalized throughout the dendrimer.
Collapse
Affiliation(s)
- G Giupponi
- Polymer IRC, Department of Physics & Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom.
| | | |
Collapse
|
29
|
Evaluation of internal structure and morphology of poly(benzyl ether) dendrimers by molecular dynamics simulations. Macromol Res 2004. [DOI: 10.1007/bf03218386] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
30
|
Ecker C, Severin N, Shu L, Schlüter AD, Rabe JP. Glassy State of Single Dendronized Polymer Chains. Macromolecules 2004. [DOI: 10.1021/ma035079h] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christof Ecker
- Department of Physics, Humboldt University Berlin, Newtonstrasse 15, D-12489 Berlin, Germany, and Chemistry Department, Free University Berlin, Takustrasse 3, D-14195 Berlin, Germany
| | - Nikolai Severin
- Department of Physics, Humboldt University Berlin, Newtonstrasse 15, D-12489 Berlin, Germany, and Chemistry Department, Free University Berlin, Takustrasse 3, D-14195 Berlin, Germany
| | - Lijin Shu
- Department of Physics, Humboldt University Berlin, Newtonstrasse 15, D-12489 Berlin, Germany, and Chemistry Department, Free University Berlin, Takustrasse 3, D-14195 Berlin, Germany
| | - A. Dieter Schlüter
- Department of Physics, Humboldt University Berlin, Newtonstrasse 15, D-12489 Berlin, Germany, and Chemistry Department, Free University Berlin, Takustrasse 3, D-14195 Berlin, Germany
| | - Jürgen P. Rabe
- Department of Physics, Humboldt University Berlin, Newtonstrasse 15, D-12489 Berlin, Germany, and Chemistry Department, Free University Berlin, Takustrasse 3, D-14195 Berlin, Germany
| |
Collapse
|
31
|
Huang B, Prantil MA, Gustafson TL, Parquette JR. The Effect of Global Compaction on the Local Secondary Structure of Folded Dendrimers. J Am Chem Soc 2003; 125:14518-30. [PMID: 14624601 DOI: 10.1021/ja037895a] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The effect of nonlocal interactions on the local structural propensities of folded dendrimers was evaluated in this work by comparing, under identical conditions, the conformational properties of isomeric dendrimers differing in their global packing efficiency. Accordingly, a modular synthesis of two series of dendrimers up to the third generation was developed to provide efficient access to isomeric dendrimers displaying different levels of overall compaction. Dendrimer compaction levels were adjusted by connecting the folded dendrons to 1,3,5-benzenetricarbonyl chloride, as the central core, via either a 2- or a 4-aminobenzamide linkage to induce relatively "compacted" or "expanded" conformations, respectively. The hydrodynamic volumes of the dendrimers were measured by time-resolved fluorescence anisotropy (TRFA) measurements as a function of the dendrimer series, generation level, and solvent. Packing efficiencies (compaction levels) were estimated by the ratio (V(h)/V(vw)) of the experimental hydrodynamic volume (V(h)) to the calculated van der Waals volume (V(vw)). The extent and stability of local helical bias was measured using circular dichroism and correlated with the packing efficiency (V(h)/V(vw)). These studies suggested that compaction plays an extremely important role in determining the secondary structural preferences of the dendrimers; however, the nature of compaction was more important than the extent of compaction.
Collapse
Affiliation(s)
- Baohua Huang
- Department of Chemistry, The Ohio State University, Columbus, OH 43210, USA
| | | | | | | |
Collapse
|
32
|
Tatewaki H, Mizutani T, Hayakawa J, Arai T, Terazima M. Energy Releasing and Conformational Dynamics of Stilbene Dendrimers upon Photoisomerization. J Phys Chem A 2003. [DOI: 10.1021/jp034785h] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hiroshi Tatewaki
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan, and Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki, 305-8571, Japan
| | - Takuo Mizutani
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan, and Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki, 305-8571, Japan
| | - Junpei Hayakawa
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan, and Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki, 305-8571, Japan
| | - Tatsuo Arai
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan, and Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki, 305-8571, Japan
| | - Masahide Terazima
- Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, 606-8502, Japan, and Department of Chemistry, University of Tsukuba, Tsukuba, Ibaraki, 305-8571, Japan
| |
Collapse
|
33
|
|
34
|
Ruiz J, Lafuente G, Marcen S, Ornelas C, Lazare S, Cloutet E, Blais JC, Astruc D. Construction of giant dendrimers using a tripodal building block. J Am Chem Soc 2003; 125:7250-7. [PMID: 12797798 DOI: 10.1021/ja021147o] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Giant pentane-soluble organo-silicon dendrimers have been synthesized using a triallylphenol brick according to a new divergent construction that uses a hydrosilylation-nucleophilic substitution sequence up to the ninth generation (G(9)). All the reactions were monitored by (1)H, (13)C, and (29)Si NMR until G(9), indicating that they were clean at the NMR accuracy until this last generation. MALDI TOF mass spectra were recorded for G(1) to G(4) and show the nature and amounts of defects that are intrinsic to the divergent construction. This technique and SEC (recorded up to G(5)) confirm the monodispersity (1.00 to 1.02) from G(1) to G(5). HRTEM and AFM images recorded for the high generations disclose the expected smooth dendrimer size progression and the globular shape. At G(9), the theoretical number of termini (TNT) is 177 407 branches (abbreviation: G(9)-177 047). It is estimated that more than 10(5) terminal branches are actually present in the G(9) dendrimer, far beyond the De Gennes "dense-packing" limit (6000 branches), and it is believed that the branch termini turn inside the dendrimer toward the core. This is corroborated by lower reaction rates and yields for the highest generation numbers presumably due to intradendritic reactions. It is probable that the dendritic construction is limited by the density of branches inside the dendrimer, i.e., far beyond the dense-packing limit.
Collapse
Affiliation(s)
- Jaime Ruiz
- Laboratoire de Chimie Organique et Organométallique, UMR CNRS No. 5802, Université Bordeaux I, 33405 Talence Cedex, France
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Buschhaus B, Bauer W, Hirsch A. Synthesis and chiroptical properties of a new type of chiral depsipeptide dendrons. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00459-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
36
|
Iavarone AT, Williams* ER. Mechanism of charging and supercharging molecules in electrospray ionization. J Am Chem Soc 2003; 125:2319-27. [PMID: 12590562 PMCID: PMC1343448 DOI: 10.1021/ja021202t] [Citation(s) in RCA: 259] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The origin of the extent of charging and the mechanism by which multiply charged ions are formed in electrospray ionization have been hotly debated for over a decade. Many factors can affect the number of charges on an analyte ion. Here, we investigate the extent of charging of poly(propyleneimine) dendrimers (generations 3.0 and 5.0), cytochrome c, poly(ethylene glycol)s, and 1,n-diaminoalkanes formed from solutions of different composition. We demonstrate that in the absence of other factors, the surface tension of the electrospray droplet late in the desolvation process is a significant factor in determining the overall analyte charge. For poly(ethylene glycol)s, 1,n-diaminoalkanes, and poly(propyleneimine) dendrimers electrosprayed from single-component solutions, there is a clear relationship between the analyte charge and the solvent surface tension. Addition of m-nitrobenzyl alcohol (m-NBA) into electrospray solutions increases the charging when the original solution has a lower surface tension than m-NBA, but the degree of charging decreases when this compound is added to water, which has a higher surface tension. Similarly, the charging of cytochrome c ions formed from acidified denaturing solutions generally increases with increasing surface tension of the least volatile solvent. For the dendrimers investigated, there is a strong correlation between the average charge state of the dendrimer and the Rayleigh limiting charge calculated for a droplet of the same size as the analyte molecule and with the surface tension of the electrospray solvent. A bimodal charge distribution is observed for larger dendrimers formed from water/m-NBA solutions, suggesting the presence of more than one conformation in solution. A similar correlation is found between the extent of charging for 1,n-diaminoalkanes and the calculated Rayleigh limiting charge. These results provide strong evidence that multiply charged organic ions are formed by the charged residue mechanism. A significantly smaller extent of charging for both dendrimers and 1,n-diaminoalkanes would be expected if the ion evaporation mechanism played a significant role.
Collapse
|
37
|
Stone DL, Smith DK, McGrail PT. Ferrocene encapsulated within symmetric dendrimers: a deeper understanding of dendritic effects on redox potential. J Am Chem Soc 2002; 124:856-64. [PMID: 11817961 DOI: 10.1021/ja0117478] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Ferrocene has been encapsulated within a symmetric ether-amide dendritic shell and its redox potential monitored in a variety of solvents. The dendritic effect generated by the branched shell is different in different solvents. In less polar, non hydrogen bond donor solvents, attachment of the branched shell to ferrocene increases its E(1/2), indicating that oxidation to ferrocenium (charge buildup) becomes thermodynamically hindered by the dendrimer, a result explained by the dendrimer providing a less polar medium than that of the surrounding electrolyte solution. The effect of electrolyte concentration on redox potential was also investigated, and it was shown that the concentration of "innocent" electrolyte has a significant effect on the redox potential by increasing the overall polarity of the surrounding medium. Dendritic destabilization of charge buildup is in agreement with the majority of reported dendritic effects. A notable exception to this is provided by the asymmetric ferrocene dendrimers previously reported by Kaifer and co-workers, in which the branching facilitated oxidation, and it is proposed that in this case the dendritic effect is generated by a different mechanism. Interestingly, in methanol, the new symmetric ferrocene dendrimer exhibited almost no dendritic effect, a result explained by the ability of methanol to interact extensively with the branched shell, generating a more open superstructure. By comparison of all the new data with other reports, this study provides a key insight into the structure-activity relationships which control redox processes in dendrimers and also an insight into the electrochemical process itself.
Collapse
Affiliation(s)
- Diane L Stone
- Department of Chemistry, University of York, Heslington, York, YO10 5DD, UK
| | | | | |
Collapse
|
38
|
Weyermann P, Diederich F, Gisselbrecht JP, Boudon C, Gross M. Dendritic Iron Porphyrins with Tethered Axial Ligands: New Model Compounds for Cytochromes. Helv Chim Acta 2002. [DOI: 10.1002/1522-2675(200202)85:2<571::aid-hlca571>3.0.co;2-y] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
39
|
Zingg A, Felber B, Gramlich V, Fu L, Collman J, Diederich F. Dendritic Iron(II) Porphyrins as Models for Hemoglobin and Myoglobin: Specific Stabilization of O2 Complexes in Dendrimers with H-Bond-Donor Centers. Helv Chim Acta 2002. [DOI: 10.1002/1522-2675(200201)85:1<333::aid-hlca333>3.0.co;2-h] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
40
|
Grayson SM, Fréchet JM. Convergent dendrons and dendrimers: from synthesis to applications. Chem Rev 2001; 101:3819-68. [PMID: 11740922 DOI: 10.1021/cr990116h] [Citation(s) in RCA: 1173] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S M Grayson
- Department of Chemistry, University of California, Berkeley, California 94720-1460, USA
| | | |
Collapse
|
41
|
Verheyde B, Maes W, Dehaen W. The use of 1,3,5-triazines in dendrimer synthesis. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2001. [DOI: 10.1016/s0928-4931(01)00368-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
42
|
Synthesis and chiroptical properties of amphiphilic dendrimers based on 2,3-dihydroxybenzyl alcohol. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00957-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
43
|
Gandhi P, Huang B, Gallucci JC, Parquette JR. Effect of terminal group sterics and dendron packing on chirality transfer from the central core of a dendrimer. Org Lett 2001; 3:3129-32. [PMID: 11574012 DOI: 10.1021/ol016409q] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[structure: see text] The conformational properties of intramolecularly hydrogen-bonded dendrimers constructed from (S)-1,1'-bi-2-naphthol as a chiral central core are described. Circular dichroism studies revealed that chirality transfer to the periphery occurs only when sterically demanding terminal esters are employed and when packing interactions are present.
Collapse
Affiliation(s)
- P Gandhi
- Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA
| | | | | | | |
Collapse
|
44
|
Laufersweiler MJ, Rohde JM, Chaumette JL, Sarazin D, Parquette JR. Synthesis, aggregation, and chiroptical properties of chiral, amphiphilic dendrimers. J Org Chem 2001; 66:6440-52. [PMID: 11559197 DOI: 10.1021/jo010423z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The syntheses of amphiphilic dendrimers based on 3,5-dihydroxybenzyl alcohol containing tri- or tetrafunctional chiral central cores and allyl ester termini are described. Water solubility is imparted to the dendrimers via a palladium-catalyzed deprotection of the peripheral allyl esters. This method affords complete deprotection of the carboxylate surface because, in contrast to the basic hydrolysis of methyl ester termini, the solubility of partially hydrolyzed intermediates is maintained throughout the course of the deprotection, thereby avoiding precipitation during the reaction. Chiroptical analysis indicates that the structure of the dendrimers collapses in water, resulting in an increased steric effect upon the central core that is manifested by lower optical rotatory power. However, contributions to the chiroptical properties from the dendron branch segments were not evident in water or organic media, suggesting that chiral substructures were not developing in the branch segments of the dendrimers. Multiangle light scattering studies revealed that the dendrimers experienced significant aggregation in aqueous media that decreased at higher generations. This behavior could be rationalized by a change in conformational preference from a disklike conformation at low generations to a more globular conformation at higher generations.
Collapse
Affiliation(s)
- M J Laufersweiler
- The Ohio State University, Department of Chemistry, Columbus, OH 43210, USA
| | | | | | | | | |
Collapse
|
45
|
Riley JM, Alkan S, Chen A, Shapiro M, Khan WA, Murphy, WR, Hanson JE. Pyrene-Labeled Poly(aryl ether) Monodendrons: Synthesis, Characterization, Diffusion Coefficients, and Photophysical Studies. Macromolecules 2001. [DOI: 10.1021/ma0007886] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jeanne M. Riley
- Department of Chemistry, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey 07079-2694, and Novartis Pharmaceuticals Corporation, 556 Morris Avenue, Summit, New Jersey 07901-1398
| | - Sibel Alkan
- Department of Chemistry, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey 07079-2694, and Novartis Pharmaceuticals Corporation, 556 Morris Avenue, Summit, New Jersey 07901-1398
| | - Aidi Chen
- Department of Chemistry, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey 07079-2694, and Novartis Pharmaceuticals Corporation, 556 Morris Avenue, Summit, New Jersey 07901-1398
| | - Michael Shapiro
- Department of Chemistry, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey 07079-2694, and Novartis Pharmaceuticals Corporation, 556 Morris Avenue, Summit, New Jersey 07901-1398
| | - Wajiha A. Khan
- Department of Chemistry, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey 07079-2694, and Novartis Pharmaceuticals Corporation, 556 Morris Avenue, Summit, New Jersey 07901-1398
| | - W. Rorer Murphy,
- Department of Chemistry, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey 07079-2694, and Novartis Pharmaceuticals Corporation, 556 Morris Avenue, Summit, New Jersey 07901-1398
| | - James E. Hanson
- Department of Chemistry, Seton Hall University, 400 South Orange Avenue, South Orange, New Jersey 07079-2694, and Novartis Pharmaceuticals Corporation, 556 Morris Avenue, Summit, New Jersey 07901-1398
| |
Collapse
|
46
|
Hecht S, Fréchet JMJ. Dendritisch eingeschlossene aktive Zentren: Anwendung des Isolationsprinzips der Natur in der Biomimetik und den Materialwissenschaften. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010105)113:1<76::aid-ange76>3.0.co;2-f] [Citation(s) in RCA: 126] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
47
|
Hecht S, Fréchet JMJ. Dendritic Encapsulation of Function: Applying Nature's Site Isolation Principle from Biomimetics to Materials Science. Angew Chem Int Ed Engl 2001; 40:74-91. [PMID: 11169692 DOI: 10.1002/1521-3773(20010105)40:1<74::aid-anie74>3.0.co;2-c] [Citation(s) in RCA: 754] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The convergence of our understanding of structure-property relationships for selected biological macromolecules and our increased ability to prepare large synthetic macromolecules with a structural precision that approaches that of proteins have spawned a new area of research where chemistry and materials science join with biology. While evolution has enabled nature to perfect processes involving energy transfer or catalysis by incorporating functions such as self-replication and repair, synthetic macromolecules still depend on our synthetic skills and abilities to mesh structure and function in our designs. Clearly, we can take advantage of our understanding of natural systems to mimic the structural features that lead to optimized function. For example, numerous biological systems make use of the concept of site isolation whereby an active center or catalytic site is encapsulated, frequently within a protein, to afford properties that would not be encountered in the bulk state. The ability of the dendritic shell to encapsulate functional core moieties and to create specific site-isolated nanoenvironments, and thereby affect molecular properties, has been explored. By utilizing the distinct properties of the dendrimer architecture active sites that have either photophysical, photochemical, electrochemical, or catalytic functions have been placed at the core. Applying the general concept of site isolation to problems in materials research is likely to prove extremely fruitful in the long term, with short-term applications in areas such as the construction of improved optoelectronic devices. This review focuses on the evolution of a natural design principle that contributes to bridging the gap between biology and materials science. The recent progress in the synthesis of dendrimer-encapsulated molecules and their study by a variety of techniques is discussed. These investigations have implications that range from the preliminary design of artificial enzymes, catalysts, or light-harvesting systems to the construction of insulated molecular wires, light-emitting diodes, and fiber optics.
Collapse
Affiliation(s)
- Stefan Hecht
- Department of Chemistry University of California Berkeley, CA 94720-1460 (USA)
| | | |
Collapse
|
48
|
Hecht S, Fréchet JMJ. Dendritic Encapsulation of Function: Applying Nature's Site Isolation Principle from Biomimetics to Materials Science. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3773(20010105)40:1%3c74::aid-anie74%3e3.0.co%3b2-c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
49
|
Hecht S, Fréchet JMJ. Dendritic Encapsulation of Function: Applying Nature's Site Isolation Principle from Biomimetics to Materials Science. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3773(20010105)40:1%3c74::aid-anie74%3e3.0.co;2-c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
50
|
|