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

US5151532A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

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

Key dates

• Filing date: Jun 27, 1991
• Grant date: Sep 29, 1992
• Expiry date: Jun 27, 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 preparation of high-purity tetrachloro-1,4-benzoquinone by the action of hydrogen peroxide and hydrochloric acid on hydroquinone, which comprises causing 3.8 top 4.2 times the molar quantity of 30 to 37% hydrochloric acid and 1.9 to 2.1 times the molar quantity of 50 to 35% hydrogen peroxide, to act at 5 to 50.degree. C. on 1 mole of hydroquinone in at least 12 times the molar quantity of 30 to 37% hydrochloric acid, then heating the resulting suspension, which essentially contains 2,5-dichlorohydroquinone, to 45 to 55.degree. C. and again causing to act on it, at 50 to 95.degree. C., 3.8 to 4.2 times the molar quantity of 30 to 37% hydrochloric acid and 1.9 to 2.1 times the molar quantity of 50 to 35% hydrogen peroxide, in each case based on the hydroquinone used, and finally adding to the suspension, which is now essentially composed of trichloro-1,4-benzoquinone, 1.9 to 2.1 times the molar quantity of hydrochloric acid of the said concentration range, and 0.95 to 1.05 times the molar quantity of hydrogen peroxide of the said concentration range, in each case based on the hydroquinone used, at 95 to 115.degree. C., sufficiently slowly for no chlorine to escape.