As (i think it was) Azole once noted, phenols in alkaline medium form phenolates, which are more susceptible to electrophylic substitution than phenols themselves by order a of thousand. That's why phenol ethers usually don't work in alkaline phenol formylations.
Now - i want to draw everyone's attention to the fact which i have myself posted a long while ago, but completely forgot until now. I'm talking about
Post 300201
(Antoncho: "3-methyl-2,5-diMeO-benzaldehyde", Novel Discourse), namely about this Example 1:
As you can see, what we have here is a much easier (non-unhydrous, no time-consuming distillations etc) reaction, which uses essentially the same components (a base and a HCHO source)
but leads to a completely different product - the benzyl alcohol instead of the benzaldehyde.
Additionally to that, this variation of hydroxymethylation
Post 235445 (missing)
(Antoncho: "Formylations", Chemistry Discourse) also uses paraform in boiling toluene - only with an acidic catalyst (does that mean it can bee used on phenol ethers as well?).
Now, with this reaction the total equation is pretty clear:
Ph-OH + HCHO ---> 2Ph(-OH)CH
2OH ,
but with the original formylation in question - i'm totally lost... Where do the 'extra' 2 hydrogens go? Reduce Mg
++? Highly unlikely, to say the least...
Does anyone have ideas on that?
Puzzled,
Antoncho