- 関
- intramolecularly
WordNet
- within the molecule; occurring by a reaction between different parts of the same molecule
Wikipedia preview
出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2015/11/20 00:57:57」(JST)
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Intramolecular in chemistry describes a process or characteristic limited within the structure of a single molecule, a property or phenomenon limited to the extent of a single molecule.
Contents
- 1 Examples
- 2 Molecular tethers
- 3 See also
- 4 References
Examples
- intramolecular hydride transfer (transfer of a hydride ion from one part to another within the same molecule)
- intramolecular hydrogen bond (a hydrogen bond formed between two functional groups of the same molecule)
In intramolecular organic reactions, two reaction sites are contained within a single molecule. This creates a very high effective concentration (resulting in high reaction rates), and, therefore, many intramolecular reactions that would not occur as an intermolecular reaction between two compounds take place.
Examples of intramolecular reactions are the Smiles rearrangement, the Dieckmann condensation and the Madelung synthesis.
Molecular tethers
In a niche concept called molecular tethers, otherwise-intermolecular reactions can be made temporarily intramolecular by anchoring both reactions by a tether with all the advantages associated to it. Popular choices of tether contain a carbonate ester, boronic ester, silyl ether, or a silyl acetal link (silicon tethers)[1] which are fairly inert in many organic reactions yet can be cleaved by specific reagents. The main hurdle for this strategy to work is selecting the proper length for the tether and making sure reactive groups have an optimal orientation with respect to each other. An examples is a Pauson-Khand reaction of an alkene and an alkyne tethered together via a silyl ether [2]
In this particular reaction, the tether angle bringing the reactive groups together is effectively reduced by placing isopropyl groups on the silicon atom via the Thorpe-Ingold effect. No reaction takes place when these bulky groups are replaced by smaller methyl groups.
Another example is a photochemical [2+2]cycloaddition with two alkene groups tethered through a silicon acetal group (racemic, the other enantiomer not depicted), which is subsequently cleaved by TBAF yielding the endo-diol.
Without the tether, the exo isomer forms.[3]
See also
References
- ^ Bracegirdle, S.; Anderson, E. A. Chem. Soc. Rev., 2010, 39, 4114 - 4129, doi:10.1039/C0CS00007H
- ^ The use of silicon-based tethers for the Pauson-Khand reaction Dobbs A, Miller I, Martinovic S Beilstein Journal of Organic Chemistry, 2007 3:21 ( 6 July 2007 ) Article link
- ^ Diastereoselective intramolecular photochemical [2 + 2] cycloaddition reactions of tethered l-(+)-valinol derived tetrahydrophthalimides Kevin I. Booker-Milburn, Sirin Gulten and Andrew Sharpe Chem. Commun., 1997, 1385 - 1386, doi:10.1039/a702386c
UpToDate Contents
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English Journal
- Curcumin amorphous solid dispersions: the influence of intra and intermolecular bonding on physical stability.
- Wegiel LA1, Zhao Y, Mauer LJ, Edgar KJ, Taylor LS.
- Pharmaceutical development and technology.Pharm Dev Technol.2014 Dec;19(8):976-86. doi: 10.3109/10837450.2013.846374. Epub 2013 Nov 6.
- We have investigated the physical stability of amorphous curcumin dispersions and the role of curcumin-polymer intermolecular interactions in delaying crystallization. Curcumin is an interesting model compound as it forms both intra and intermolecular hydrogen bonds in the crystal. A structurally di
- PMID 24192454
- Synthesis and spectroscopic characterization of a fluorescent pyrrole derivative containing electron acceptor and donor groups.
- Almeida AK1, Monteiro MP2, Dias JM3, Omena L2, da Silva AJ1, Tonholo J1, Mortimer RJ4, Navarro M3, Jacinto C2, Ribeiro AS5, de Oliveira IN6.
- Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.Spectrochim Acta A Mol Biomol Spectrosc.2014 Jul 15;128:812-8. doi: 10.1016/j.saa.2014.03.012. Epub 2014 Mar 20.
- The synthesis and fluorescence characterization of a new pyrrole derivative (PyPDG) containing the electron donor-acceptor dansyl substituent is reported. The effects of temperature and solvent polarity on the steady-state fluorescence of this compound are investigated. Our results show that PyPDG e
- PMID 24704598
- Vibrational spectroscopic study, charge transfer interaction and nonlinear optical properties of l-asparaginium picrate: A density functional theoretical approach.
- Elleuch N1, Amamou W2, Ben Ahmed A3, Abid Y3, Feki H3.
- Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.Spectrochim Acta A Mol Biomol Spectrosc.2014 Jul 15;128:781-9. doi: 10.1016/j.saa.2014.02.159. Epub 2014 Mar 12.
- Single crystals of L-asparaginium picrate (LASP) were grown by slow evaporation technique at room temperature and were the subject of an X-ray powder diffraction study to confirm the crystalline nature of the synthesized compound. FT-IR and Raman spectra were recorded and analyzed with the aid of th
- PMID 24704485
Japanese Journal
- A strategy for sequence control in vinyl polymers via iterative controlled radical cyclization.
- INTER- AND INTRAMOLECULAR DIELS-ALDER REACTION OF ETHENETRICARBOXYLATE DERIVATIVES
- Heterocycles : an international journal for reviews and communications in heterocyclic chemistry 92(3), 485-510, 2016-03-01
- NAID 40020766398
- Molecular mechanism of phototropin light signaling (JPR Symposium : The Cutting Edge of Photoresponse Mechanisms : Photoreceptor and Signaling Mechanism)
Related Links
- intramolecular 【形】分子内の - アルクがお届けする進化するオンライン英和・和英辞書データベース。一般的な単語や連語から、イディオム、専門用語、スラングまで幅広く収録。
- Intramolecular contacts are encountered. Intramolecular disulfide bonds. Intramolecular hydrogen bonding, all the C=O groups in both oligomers are located inwardly. Intramolecular hydrogen atom transfer in cations. Intramolecular interactions to promote bulk electronic properties is of particular interest.
Related Pictures
★リンクテーブル★
[★]
- 英
- intramolecular、intramolecularly
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分子内転移酵素
- 関
- mutase
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- 関
- intramolecular
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分子内酸化還元酵素