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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/10/20 16:54:31」(JST)

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Deprotonation is the removal of a proton (H⁺) from a molecule, forming the conjugate base. The proton removal decreases positive charge in the molecule and increases negative charge. Deprotonation usually occurs from the donation of electrons or acceptance of the proton using a base, which forms its conjugate acid.

The relative ability of a molecule to give up a proton is measured by its pK_a value. A low pK_a value indicates that the compound is acidic and will easily give up its proton to a base. The pK_a of a compound is determined by many things, but the most significant is the stability of the conjugate base. This is primarily determined by the ability (or inability) of the conjugated base to stabilize negative charge. One of the most important ways of assessing a conjugate base's ability to distribute negative charge is using resonance. Electron withdrawing groups (which can stabilize the molecule by increasing charge distribution) or electron donating groups (which destabilize by decreasing charge distribution) present on a molecule also determine its pK_a. The solvent used can also assist in the stabilization of the negative charge on a conjugated base.

Bases used to deprotonate depend on the pK_a of the compound. When the compound is not particularly acidic, and, as such, the molecule does not give up its proton easily, a base stronger than the commonly known hydroxides is required. Hydrides are one of the many types of powerful deprotonating agents. Common hydrides used are sodium hydride and potassium hydride. The hydride forms hydrogen gas with the proton from the other molecule. However, the production of hydrogen also means that deprotonation using agents that release hydrogen is dangerous and should be done in an inert atmosphere (e.g., nitrogen), as the hydrogen can ignite with the oxygen in the air.

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English Journal

The change in excited-state proton transfer kinetics of 1-naphthol i micelles upon the binding of polymers: The influence of hyaluronan hydration.

Mondek J1, Pekař M2.
Carbohydrate polymers.Carbohydr Polym.2015 Sep 20;129:168-74. doi: 10.1016/j.carbpol.2015.04.060. Epub 2015 May 7.
The fast deprotonation of 1-naphthol was studied in aqueous solution and in polymer-cetyltrimethylammonium bromide (CTAB) mixtures using picosecond fluorescence spectroscopy to study the influence of hyaluronan hydration in polymer-surfactant interactions. The aqueous micelle solution showed the exp
PMID 26050902

A colorimetric and absorption ratiometric anion sensor based on indole & hydrazide binding units.

Zou L1, Yan B1, Pan D1, Tan Z1, Bao X2.
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy.Spectrochim Acta A Mol Biomol Spectrosc.2015 Sep 5;148:78-84. doi: 10.1016/j.saa.2015.03.109. Epub 2015 Apr 3.
A colorimetric and absorption ratiometric anion sensor (L) based on indole and hydrazide binding units was designed and synthesized, and its recognition & sensing properties towards different anions were studied by naked-eye observations, UV-vis and (1)H NMR titration spectra. Sensor L could sel
PMID 25875028

Surface protonation/deprotonation controlled instant affinity switch of nano drug vehicle (NDV) for pH triggered tumor cell targeting.

Wang Z1, Ma G1, Zhang J1, Yuan Z1, Wang L1, Bernards M2, Chen S3.
Biomaterials.Biomaterials.2015 Sep;62:116-27. doi: 10.1016/j.biomaterials.2015.05.020. Epub 2015 May 16.
To realize a fast and selective capture of nano drug vehicles (NDVs) by malignant tumors, an instant affinity switchable NDV based on pH-sensitive surface protonation was prepared. This NDV is prepared from a zwitterionic polymer system with an ultra resistant poly(carboxybetaine) (pCB) shell and su
PMID 26046750

Japanese Journal

Study on radiation chemistry of fluorinated polymers for EUV resist

Nomura Naoya,Okamoto Kazumasa,Yamamoto Hiroki,Kozawa Takahiro,Fujiyoshi Ryoko,Umegaki Kikuo
Jpn. J. Appl. Phys. 54(6S1), 06FE03, 2015-06-02
… The lower acid generation efficiency in fluorinated polymers was due to not only the reaction between fluorinated polymers and electrons but also the lower deprotonation efficiency of the radical cation of the fluorinated polymer. …
NAID 150000110750

Oxidation and Deprotonation of a Ruthenium(Ⅱ) Complex with Quinoline-2-carbaldehyde (Pyridine-2-carbonyl)hydrazone and Formation of Hydrazonato-Bridged Heterodimetallic Complexes

Mori Asami,Suzuki Takayoshi,Sunatsuki Yukinari [他]
Bulletin of the Chemical Society of Japan 88(3), 480-489, 2015-03
NAID 40020392453

Pulse radiolysis study of polystyrene-based polymers with added photoacid generators: Reaction mechanism of extreme-ultraviolet and electron-beam chemically amplified resist

Okamoto Kazumasa,Yamamoto Hiroki,Kozawa Takahiro,Fujiyoshi Ryoko,Umegaki Kikuo
Jpn. J. Appl. Phys. 54(2), 026501, 2015-01-06
… The deprotonation kinetics of the radical cation of poly(4-hydroxystyrene) (PHS) in solutions with and without PAG shows only a small difference. …
NAID 150000110155