| 摘要 |
<p>Hydroxyethylmercaptobenzaldehydes and oxidation products thereof of the formula (I) …<IMAGE>… in which R denotes a hydrogen, fluorine, chlorine, bromine or iodine atom, m denotes the number 0 to 2, n the number 1 or 2 and p the number 0 or 1, with the proviso that p is 0 if m is 0 and the side chain -S(O)m-CH2-CH2-OH is in the ortho and/or para position relative to the aldehyde or carboxyl group, are prepared by condensing 1 mol of a halobenzaldehyde of the formula (II) …<IMAGE>… in which R, X, Y and Z represent hydrogen, fluorine, chlorine, bromine or iodine atoms, with the proviso that R, X, Y and Z together can be 1, 2 or 3 halogen atoms, in which R is a halogen atom if R, X, Y and Z together are 3 halogen atoms, in aqueous medium with about 1.0 to 1.5 mol of mercaptoethanol (per halogen atom to be exchanged) in the presence of acid-binding agents at about 70 DEG C to about 150 DEG C to give the hydroxyethylmercaptobenzaldehydes, which are then oxidised to the hydroxyethylsulphonylbenzoic acids using at least the amount of hydrogen peroxide required in each case at about 40 DEG C to about 110 DEG C in the presence of a tungsten(VI) compound as the catalyst.</p> |
