Boffis - 29-5-2015 at 13:26
I have aquired some sulfoguaiacol (2-Hydroxymethoxybenzene-sulphonic acid as K salt) and my target compound is 2-amino-4-nitrophenol-6-sulphonic acid,
an azo dye intermediate. (some online sources such as COSSH and other safety data sites claim that it is guaiacol-4-sulphonic acid i.e.
2-methoxyphenol-4-sulphonic acid but these are a minority.)
My planned route is to dinitrate the sulfoguaiacol with mixed acids to give the 2,4-dinitro (relative to the hydroxymethoxy group) and then selective
reduce the 2-nitro group with sodium sulphide as with picramic acid etc. The problem is the hydroxymethoxy group instead of a hydroxy group.
The hydroxymethoxy group is in effect the aromatic hemiacetal of formaldehyde but is it as readily hydrolysable as the aliphatic analog? Will the
sulphuric acid remove the hydroxymethyl (HO-CH2-) portion or could it remain and suffer nitration to an oxymethyl nitrate group?
Any ideas welcome!
Pumukli - 30-5-2015 at 04:37
There is no "hydroxymethoxy" group in sulfoguajacol!
Guajacol is 2-methoxy-phenol!
You have 1-hydroxy-2-methoxy-4-benzenesulphonic acid as starting material.
Boffis - 1-6-2015 at 01:41
@Pumukli; if only it were that simple! Take a cruise around the internet and you will soon see the problem. Only one site I have found give what I
believe to be the correct definition the European Committee for vetenery medical product. It states that "Sulfoguaiacol" is potassium
hydroxy-2-methoxy-benzene-4-sulphonate hemihydrate. The ChemBook site give the same composition as you. However:
from PharmaWiki (German site)
from chemspider etc
The second formula picture the 3-sulphonic acid looks unlikely as it is meta to the -OH. Direct sulphonation of guaiacol should give mainly 4 and some
2 substitution relative to the OH group