Process for the preparation of tetrachloro-1,4-benzoquinone

US5559257A · kind A · utility

Assignee

• Hoechst A.G. · DE

Inventors

• Otto Arndt · Hofheim, DE
• Wolfgang Tronich

Key dates

• Filing date: Feb 22, 1995
• Grant date: Sep 24, 1996
• Expiry date: Feb 22, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C46/06
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The invention relates to a process for the preparation of tetrachloro-1,4-benzoquinone of high purity by the action of chlorine and concentrated hydrochloric acid on hydroquinone, which involves introducing a portion of the hydroquinone to be employed into initially introduced hydrochloric acid containing catalytic amounts of iron(III) ions and an anionic dispersant, introducing chlorine gas into this solution at a temperature from 20.degree. to 107.degree. C., then adding the residual quantity of hydroquinone as a solid or in solution, raising the temperature to from 80.degree. to 107.degree. C. while continuing to pass in gaseous chlorine, adding, after the introduction of gaseous chlorine has ended, a relatively high-boiling organic solvent which is not miscible with hydrochloric acid, and subsequently subjecting the reaction mixture to thermal aftertreatment.