Multihydroxy-functional oligophenylene oxide obtainable by reacting a compound containing hydroxyaryl comprising at least three hydroxyaryl groups according to formula (I), wherein R = an aromatic, aliphatic or cycloaliphatic group containing 1-50 carbon atoms, R, R = H or an aromatic, aliphatic or cycloaliphatic group containing 1-50 carbon atoms, or two of the R, R or R groups together constitute a ring structure containing 4-50 carbon atoms with a polyphenylene oxide in the presence of a catalyst complex comprising a transition metal and and amine
