非プロトン性の、非プロトンの

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/04/17 16:25:21」(JST)

wiki en

In chemistry, a protic solvent is a solvent that has a hydrogen atom bound to an oxygen (as in a hydroxyl group) or a nitrogen (as in an amine group). In general terms, any solvent that contains labile H⁺ is called a protic solvent. The molecules of such solvents readily donate protons (H⁺) to reagents. Conversely, aprotic solvents cannot donate hydrogen.

Polar protic solvents

Polar protic solvents are often used to dissolve salts. In general, these solvents have high dielectric constants and high polarity.

Common characteristics of protic solvents :

solvents display hydrogen bonding
solvents have an acidic hydrogen (although they may be very weak acids such as ethanol)
solvents dissolve salts
- cations by unshared free electron pairs
- anions by hydrogen bonding

Examples include water, most alcohols, formic acid, hydrogen fluoride, and ammonia. Polar protic solvents are favorable for S_N1 reactions, while polar aprotic solvents are favorable for S_N2 reactions.

Polar aprotic solvents

Polar aprotic solvents are solvents that will dissolve many salts, but lack an acidic hydrogen. These solvents generally have intermediate dielectric constants and polarity. Although discouraging use of the term "polar aprotic", IUPAC describes such solvents as having both high dielectric constants and high dipole moments, an example being acetonitrile. Other solvents meeting IUPAC's criteria include DMF, HMPA, and DMSO.^[1]

Common characteristics of aprotic solvents:

solvents that can accept hydrogen bonds
solvents do not have acidic hydrogen centers (acetone and esters fail this criterion)
solvents dissolve organic salts such as tetraethylammonium iodide

Polar aprotic solvents are often essential for reactions that involve strong bases, such as reactions involving Grignard reagents or n-butyllithium. These reagents react with protic solvents:

C₄H₉Li + HOCH₃ → C₄H10 + LiOCH₃

An example of a dipolar aprotic solvent is methylpyrrolidone.

Properties of common solvents

The solvents are grouped into non-polar, polar aprotic, and polar protic solvents and ordered by increasing polarity. The polarity is given as the dielectric constant. The properties of solvents that exceed those of water are bolded.

Solvent	Chemical Formula	Boiling point	Dielectric constant	Density	Dipole moment (D)
Non-Polar Solvents
Hexane	CH₃-CH₂-CH₂-CH₂-CH₂-CH₃	69 °C	2.0	0.655 g/ml	0.00 D
Benzene	C₆H₆	80 °C	2.3	0.879 g/ml	0.00 D
Toluene	C₆H₅-CH₃	111 °C	2.4	0.867 g/ml	0.36 D
1,4-Dioxane	/-CH₂-CH₂-O-CH₂-CH₂-O-\	101 °C	2.3	1.033 g/ml	0.45 D
Chloroform	CHCl₃	61 °C	4.8	1.498 g/ml	1.04 D
Diethyl ether	CH₃-CH₂-O-CH₂-CH₃	35 °C	4.3	0.713 g/ml	1.15 D
Dichloromethane (DCM)	CH₂Cl₂	40 °C	9.1	1.3266 g/ml	1.60 D
Polar Aprotic Solvents
tetrahydrofuran (THF)	/-CH₂-CH₂-O-CH₂-CH₂-\	66 °C	7.5	0.886 g/ml	1.75 D
ethyl acetate (EtOAc)	CH₃-C(=O)-O-CH₂-CH₃	77 °C	6.0	0.894 g/ml	1.78 D
acetone	CH₃-C(=O)-CH₃	56 °C	21	0.786 g/ml	2.88 D
dimethylformamide (DMF)	H-C(=O)N(CH₃)₂	153 °C	38	0.944 g/ml	3.82 D
acetonitrile (MeCN)	CH₃-C≡N	82 °C	37	0.786 g/ml	3.92 D
dimethyl sulfoxide (DMSO)	CH₃-S(=O)-CH₃	189 °C	47	1.092 g/ml	3.96 D
Polar Protic Solvents
formic acid	H-C(=O)OH	101 °C	58	1.21 g/ml	1.41 D
n-butanol	CH₃-CH₂-CH₂-CH₂-OH	118 °C	18	0.810 g/ml	1.63 D
isopropanol (IPA)	CH₃-CH(-OH)-CH₃	82 °C	18	0.785 g/ml	1.66 D
nitromethane	CH₃-NO₂	100–103 °C	35.87	1.1371 g/ml	3.56 D
ethanol (EtOH)	CH₃-CH₂-OH	79 °C	30	0.789 g/ml	1.69 D
methanol (MeOH)	CH₃-OH	65 °C	33	0.791 g/ml	1.70 D
Acetic acid (AcOH)	CH₃-C(=O)OH	118 °C	6.2	1.049 g/ml	1.74 D
Water	H-O-H	100 °C	80	1.000 g/ml	1.85 D

References

^ http://goldbook.iupac.org/D01751.html

Loudon, G. Mark. Organic Chemistry 4th ed. New York: Oxford University Press. 2002. pg 317.

English Journal

A two-step ICT process for solvatochromic betaine pyridinium revealed by ultrafast spectroscopy, multivariate curve resolution, and TDDFT calculations.

Aloïse S, Pawlowska Z, Ruckebusch C, Sliwa M, Dubois J, Poizat O, Buntinx G, Perrier A, Maurel F, Jacques P, Malval JP, Poisson L, Piani G, Abe J.SourceLaboratoire de Spectrochimie Infrarouge et Raman CNRS UMR 8516, Université de Lille1 Sciences et Technologies, Université Lille Nord de France, Bat C5, 59655 Villeneuve d'Ascq Cedex, France. stephane.aloise@univ-lille1.fr.
Physical chemistry chemical physics : PCCP.Phys Chem Chem Phys.2012 Feb 14;14(6):1945-56. Epub 2012 Jan 9.
This work deals with the photophysics of a pyridinium betaine, 2-pyridin-1-yl-1H-benzimidazole (SBPa), based on a combination of steady-state, femtosecond photoionization (gas phase) and femtosecond transient absorption (solution) spectroscopic measurements, supported by (LR)-PCM-(TD)DFT calculation
PMID 22231287

Evidence for Alkene cis-Aminocupration, an Aminooxygenation Case Study: Kinetics, EPR Spectroscopy, and DFT Calculations.

Paderes MC, Belding L, Fanovic B, Dudding T, Keister JB, Chemler SR.SourceDepartment of Chemistry, The State University of New York at Buffalo, Buffalo, New York 14260 (USA), Fax: (+1) 716-645-6963.
Chemistry (Weinheim an der Bergstrasse, Germany).Chemistry.2012 Feb 6;18(6):1711-26. doi: 10.1002/chem.201101703. Epub 2012 Jan 11.
Alkene difunctionalization reactions are important in organic synthesis. We have recently shown that copper(II) complexes can promote and catalyze intramolecular alkene aminooxygenation, carboamination, and diamination reactions. In this contribution, we report a combined experimental and theoretica
PMID 22237868

Japanese Journal

SYNTHESIS OF BICYCLIC DIOXETANES BEARING A 4-(BENZIMIDAZOL-2-YL)-3-HYDROXYPHENYL GROUP AND THEIR BASE-INDUCED CHEMILUMINESCENT DECOMPOSITION IN AN APROTIC MEDIUM AND IN AN AQUEOUS MEDIUM

Hagiwara Hiromasa,Watanabe Nobuko,Ijuin Hisako K. [他]
Heterocycles : an international journal for reviews and communications in heterocyclic chemistry 87ﾏﾏ(1), 65-78, 2013-01-01
NAID 40019530749

Selected Examples of Gas-Phase Ion Chemistry Studies

Nibbering Nico M. M.
Mass Spectrometry 2(Special_Issue), S0002-S0002, 2013
… In addition, an example of formation of different tautomeric structures in protic and aprotic solvents under electrospray ionization conditions will be given, as established by gas-phase infrared multiphoton dissociation spectroscopy. …
NAID 130003380170

ポリエチレングリコール添加による非プロトン性溶媒中へのナトリウム塩の溶解と,それを利用した有機化合物の効率的陽極酸化反応

SAWAMURA Takahiro,TAKAHASHI Kohta,INAGI Shinsuke [他],FUCHIGAMI Toshio
電気化学および工業物理化学 81(5), 365-367, 2013
… The long-standing problem of solubility of inorganic salts in aprotic organic solvents in electroorganic synthesis has been overcome by the addition of poly(ethylene glycol) to the electrolytic solutions through cyclic voltammetry analysis and macro-scale electrolysis. …
NAID 130003376696