Tollen's Test with Salicylaldehyde I have read that Tollens' test is given by aldehydes. The aldehyde is oxidised to a carboxylate ion and silver is deposited.
My teacher had given me notes which pointed that salicylaldehyde does not give this test. However, I cannot find any explanation for the same. I have tried to search online and through books but I did not get anything.
I think it could be related to resonance from the −OH group as something similar is mentioned in my notes, but it is not elaborated. Can anyone please explain this?
Of course, the answer is resonance.  As described by Benet et al., a basic medium (pH&gt;10) favours the Tollen's reaction. On the other hand, if we want to dissolve phenol in water, we will need OH- to generate phenolate. It means the hydroxyl group of salicylaldehyde is sensitive to the high pH, and this hinders attacking the other hydroxides to the carbonyl group by further stabilizing it.