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Organic Chemistry

B | Acidity Constants for Some Organic Compounds

Organic ChemistryB | Acidity Constants for Some Organic Compounds
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B • Acidity Constants for Some Organic Compounds

B • Acidity Constants for Some Organic Compounds

Table B1
Compound pKa
CH3SO3H −1.8
CH(NO2)3  0.1
 0.3
CCl3CO2H  0.5
CF3CO2H  0.5
CBr3CO2H  0.7
HO2CCCCO2HHO2CCCCO2H  1.2; 2.5
HO2CCO2H  1.2; 3.7
CHCl2CO2H  1.3
CH2(NO2)CO2H  1.3
HCCCO2HHCCCO2H  1.9
(Z) HO2CCHCHCO2HHO2CCHCHCO2H  1.9; 6.3
 2.4
CH3COCO2H  2.4
NCCH2CO2H  2.5
CH3CCCO2HCH3CCCO2H  2.6
CH2FCO2H  2.7
CH2ClCO2H  2.8
HO2CCH2CO2H  2.8; 5.6
CH2BrCO2H  2.9
 3.0
 3.0
CH2ICO2H  3.2
CHOCO2H  3.2
 3.4
 3.5
HSCH2CO2H  3.5; 10.2
CH2(NO2)2  3.6
CH3OCH2CO2H  3.6
CH3COCH2CO2H  3.6
HOCH2CO2H  3.7
HCO2H  3.7
 3.8
 4.0
CH2BrCH2CO2H  4.0
 4.1
 4.2
H2CCHCO2HH2CCHCO2H  4.2
HO2CCH2CH2CO2H  4.2; 5.7
HO2CCH2CH2CH2CO2H  4.3; 5.4
 4.5
H2CC(CH3)CO2HH2CC(CH3)CO2H  4.7
CH3CO2H  4.8
CH3CH2CO2H  4.8
(CH3)3CCO2H  5.0
CH3COCH2NO2  5.1
 5.3
O2NCH2CO2CH3  5.8
 5.8
 6.2
 6.6
HCO3H  7.1
 7.2
(CH3)2CHNO2  7.7
 7.8
CH3CO3H  8.2
 8.5
CH3CH2NO2  8.5
 8.7
CH3COCH2COCH3  9.0
 9.3; 11.1
 9.3; 12.6
 9.4
 9.9; 11.5
 9.9
CH3COCH2SOCH3  10.0
 10.3
CH3NO2  10.3
CH3SH  10.3
CH3COCH2CO2CH3  10.6
CH3COCHO  11.0
CH2(CN)2  11.2
CCl3CH2OH  12.2
Glucose  12.3
(CH3)2CNOH(CH3)2CNOH  12.4
CH2(CO2CH3)2  12.9
CHCl2CH2OH  12.9
CH2(OH)2  13.3
HOCH2CH(OH)CH2OH  14.1
CH2ClCH2OH  14.3
 15.0
 15.4
CH3OH  15.5
H2CCHCH2OHH2CCHCH2OH  15.5
CH3CH2OH  16.0
CH3CH2CH2OH  16.1
CH3COCH2Br  16.1
 16.7
CH3CHO  17
(CH3)2CHCHO  17
(CH3)2CHOH  17.1
(CH3)3COH  18.0
CH3COCH3  19.3
 23
CH3CO2CH2CH3  25
HCCHHCCH  25
CH3CN  25
CH3SO2CH3  28
(C6H5)3CH  32
(C6H5)2CH2  34
CH3SOCH3  35
NH3  36
CH3CH2NH2  36
(CH3CH2)2NH  40
 41
 43
H2CCH2H2CCH2  44
CH4  ∼60

An acidity list covering more than 5000 organic compounds has been published: E.P. Serjeant and B. Dempsey (eds.), “Ionization Constants of Organic Acids in Aqueous Solution,” IUPAC Chemical Data Series No. 23, Pergamon Press, Oxford, 1979.

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