Process for the production of high-purity tetrachloro-1,4-benzoquinone

US5149850A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Otto Arndt · Hofheim, DE
• Theodor Papenfuhs · Frankfurt, DE

Key dates

• Filing date: Jun 28, 1991
• Grant date: Sep 22, 1992
• Expiry date: Jun 28, 2011

Classification

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

Abstract

A process for the production of high-purity tetrachloro-1,4-benzoquinone by the action of chlorine and hydrochloric acid on hydroquinone which comprises causing 1.9 to 2.1 times the molar quantity of gaseous chlorine to act at temperatures from 5.degree. to 15.degree. C. on 1 mol of hydroquinone in 6 to 7 times the molar quantity of 30 to 37% hydrochloric acid, then diluting the resulting suspension, essentially containing 2,5-dichlorohydroquinone, with 2 to 3 parts of water, relative to hydroquinone employed, and initially warming to a temperature from 20.degree. to 30.degree. C., subsequently introducing 1.9 to 2.1 times the molar quantity of chlorine gas in an air atmosphere while raising the temperature to 90.degree.-100.degree. C. with simultaneous dilution with 3.5 to 4.5 parts of water, relative to hydroquinone employed, and finally introducing 1 to 2 times the molar quantity of gaseous chlorine, relative to hydroquinone employed, at temperatures from 100.degree. to 115.degree. C.