pKa table and protecting groups

39 rows · Octet · sample of the first 8 rows

pKa values

pKa values — pKa table and protecting groups. The acidity ladder and the protecting-group cheat sheet on one page — the two things a synthesis problem asks for at the same time. Every pKa in the library with its conjugate base where the record names one, then each protecting group with what it protects and the reagents that put it on and take it off.
Compound	pKa	Conjugate base	Notes
HI¹	-10	not defined	Strongest common acid
HBr^1,2	-9	not defined	not defined
HCl^1,2	-7	not defined	not defined
H₂SO₄¹	-3	not defined	First proton
HNO₃^1,2	-1.4	not defined	not defined
H₃O⁺¹	-1.7	not defined	Hydronium ion
HSO₄⁻¹	2	not defined	Second proton of H₂SO₄
HF¹	3.2	not defined	Weak due to strong H-F bond

Built from the pkaTable and protectingGroups collections. pKa values are approximate and solvent-dependent; a lower pKa means a stronger acid and a more stable conjugate base.