Reaction of 2,5-dihydroxy-[1,4]-benzoquinone with nucleophiles – ipso-substitution vs. addition/elimination

Hubert Hettegger, Karin Steinkellner, Nele S. Zwirchmayr, Antje Potthast, Kevin J. Edgar, Thomas Rosenau

Research output: Contribution to journalArticleScientificpeer-review


2,5-Dihydroxy-[1,4]-benzoquinone (DHBQ) reacts readily with secondary amines to 2,5-diamino compounds and with thiols to the corresponding 2,5-dithioether derivatives. The literature has been inconclusive about the detailed mechanism, as both ipso-substitution at C-2/C-5 and the sequence of C-3/C-6 addition and C-2/C-5 elimination would give exactly the same products. By means of selectively 13C isotopically labelled DHBQ it was demonstrated that the reaction with morpholine is an ipso-substitution, while the reaction with benzenethiol and 1-hexanethiol proceeds according to the addition/elimination mechanism, and the reaction with the respective thiolates according to both mechanisms in parallel. Strongly acidic media cause a peculiar "OH-fluxuational"effect in DHBQ with the two quinone oxygens and the two hydroxy groups changing positions relative to the carbon skeleton while maintaining the 2,5-dihydroxy-[1,4]-diketo pattern. With this study, the mechanism of the unwanted nitrogen and sulfur fixation in cellulose fiber processing and during degradation could be better understood. This journal is

Original languageEnglish
Pages (from-to)12845-12848
Number of pages4
JournalChemical Communications
Issue number84
Publication statusPublished - 28 Oct 2020
MoE publication typeA1 Journal article-refereed


Dive into the research topics of 'Reaction of 2,5-dihydroxy-[1,4]-benzoquinone with nucleophiles – ipso-substitution vs. addition/elimination'. Together they form a unique fingerprint.

Cite this