Solubility in 5% Sodium Hydroxide Solution
Soluble
Borderline
carboxylic acids (RCO
2
H)
acetoacetic esters
sulfonic acids (RSO
3
H)
malonic esters
sulfinic acids (RSO
2
H)
1,3-diketones
phenols (ArOH)
enols (R
2
C=COH(R'))
imides (RC(O)NHC(O)R')
1
o
& 2
o
aliphatic nitro compounds (RNO
2
)
oximes (R
2
C=NOH)
unsubstituted arylsulfonamides (ArSO
2
NHR)
thiophenols (ArSH)
Notes:
A compound is deemed "soluble" in NaOH if it is significantly more soluble than in water.
Some sodium salts of highly substituted phenols are insoluble in 5% NaOH.
The same is true for some carboxylic acids.