Process for making 2,5-dihalogenated phenol

Patent metadata

Field	Value
Publication number	US-9988333-B2
Application number	US-201515311951-A
Country	US
Kind code	B2
Filing date	May 18, 2015
Priority date	May 19, 2014
Publication date	Jun 5, 2018
Grant date	Jun 5, 2018

Abstract

The present invention relates to a process for reacting chemical compounds comprising the step of reacting a compound of formula (IV)

wherein Hal is independently selected from Cl or Br, and X − is a monovalent anion, in the presence of an inorganic acid, wherein the aqueous inorganic acid has a concentration of at least about 60%, at a temperature of about 140° C. to about 250° C., to obtain a compound of formula (V)

wherein Hal is as defined above.

First claim

The invention claimed is:

1. A process for reacting chemical compounds comprising the step of hydrolysing a compound of formula (IV)

wherein Hal is independently selected from the group consisting of Cl and Br, and X − is HSO 4 − ,
in the presence of an aqueous inorganic acid, wherein the aqueous inorganic is H 2 SO 4 , which has a concentration of at least 60% by weight, at a temperature of 140° C. to 250° C., to obtain a compound of formula (V)

wherein Hal is as defined above;
and wherein the compound of formula (IV) is provided by diazotating a compound of formula (III)

wherein Hal is as defined above;
and wherein the step of diazotating the compound of formula (III) to obtain the compound of formula (IV) is carried out in H 2 SO 4 having a concentration of at least 40% by weight in the presence of NOHSO 4 , and wherein the temperature is from 45° C. to 65° C.

2. The process of claim 1 , wherein product of formula (V) is continuously removed from the reaction system using steam distillation.

3. The process of claim 1 , wherein the concentration of the H 2 SO 4 in the hydrolysis step is at least 70% by weight.

4. The process of claim 3 , wherein at least part of the H 2 SO 4 used in the hydrolysis step is recycled.

5. The process of claim 1 , wherein the hydrolysis step is carried out at a temperature of at least 160° C.

6. The process of claim 1 , wherein NO H SO 4 is obtained by feeding NO x gas to sulfuric acid having a concentration of at least about 60% by weight, and wherein the NO x gas is a mixture of NO and NO 2 in a molar ratio of about 1:1.

7. The process of claim 1 , wherein the water used for steam distillation is recycled in a closed water loop.

8. The process of claim 1 , wherein the compound of formula (III) is obtained by reducing a compound of formula (II)

wherein Hal is independently selected from the group consisting of Cl and Br.

9. The process of claim 8 , wherein the compound of formula (II) is obtained by nitrating a compound of formula (I)

wherein Hal is independently selected from the group consisting of Cl and Br.

10. The process of claim 1 , further comprising the step of reacting the compound of formula (V) to obtain a compound of formula (VI)

wherein Hal is independently selected from the group consisting of Cl and Br, and R 1 is an alkali metal.

11. The process of claim 10 , wherein the step of reacting the compound of formula (V) to obtain a compound of formula (VI) is carried out in the presence of an alkali metal hydroxide and carbon dioxide.

12. The process of claim 10 , further comprising the step of reacting the compound of formula (VI) to obtain a compound of formula (VII)

wherein R 2 is —(C 1 -C 4 )alkyl, R 1′ is an alkali metal or —(C 1 -C 4 )alkyl, and Hal is independently selected from the group consisting of Cl and Br.

13. The process of claim 12 , further comprising the step of reacting the compound of formula (VII) to obtain a compound of formula (VIII)

wherein R 2 and Hal are as defined in claim 12 .

14. The process of claim 12 , wherein
(a) Hal is Cl; and/or
(c) R 1′ is selected from the group consisting of sodium and potassium, or R 1′ is selected from the group consisting of ethyl and methyl; and/or
(d) R 2 is selected from the group consisting of ethyl and methyl.

15. The process of claim 13 , wherein the compound of formula (VIII) is

Assignees

• Basf Se

Inventors

• Pletsch Andreas
• Holub Nicole
• Ulrich Thomas
• Kvita Petr
• Cavin Laurent

Classifications

• C07C241/02

  Preparation of hydrazines · CPC title

• C07C51/00

  Preparation of carboxylic acids or their salts, halides or anhydrides (of acids by hydrolysis of oils, fats or waxes C11C) · CPC title

• C07C37/76

  by steam distillation · CPC title

• C07C37/045 Primary

  by substitution of a group bound to the ring by nitrogen · CPC title

• C07C201/08

  by substitution of hydrogen atoms by nitro groups · CPC title