marcos n. eberlin basicidade.pdf · coord. nada de . Ácidos e bases acido arrhenius doador h....
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MARCOS N. EBERLIN
Acidez e Basicidade
Acidez OH
< R OH
O
< HClR-OH <R-H <
pKa ~ 16pKa ~ 50
pKa ~ 10pKa ~ 4
pKa ~ -7
R-NH2
pKa ~ 37
<
48p
aK
δ-δ
3 H
CH
38p
aK
δ-δ
2 H
NH
15,7p
aK
δ-δ
H
OH
3,2p
aK
δ-δ
H
F
Aumento da Acidez
Two factors to consider 1. the strength of the bond being broken, 2. the stability of the ions being formed.
pKa = -1,9
Basicidade
pKb + pKaH = 14
Basicidade
pKb = 2
MTBD - Methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene TBD - 1,5,7-Triazabicyclo[4.4.0]dec-5-ene
pKb = 5.2 DABCO