Method for producing fluorenone

Patent metadata

Field	Value
Publication number	US-12545633-B2
Application number	US-202118249179-A
Country	US
Kind code	B2
Filing date	Oct 21, 2021
Priority date	Oct 23, 2020
Publication date	Feb 10, 2026
Grant date	Feb 10, 2026

Abstract

Provided is a method for producing fluorenone comprising an oxidation step of oxidizing fluorene in the presence of an aliphatic carboxylic acid having 2 to 3 carbon atoms, a metal catalyst, a bromine compound, and oxygen, a solvent removal step of removing the aliphatic carboxylic acid, a heating step at 120 to 350° C., and a distillation step in the order indicated.

First claim

The invention claimed is:

1 . A method for producing fluorenone, comprising:
oxidizing fluorene in the presence of an aliphatic carboxylic acid having 2 to 3 carbon atoms, a metal catalyst, a bromine compound, and oxygen to obtain an oxidation reaction product; removing the aliphatic carboxylic acid from the oxidation reaction product to produce a mixture; heating the mixture at a temperature in a range of 120 to 350° C. to obtain a heat-treated mixture; and a distilling the heat-treated mixture.

2 . The method for producing fluorenone according to claim 1 , wherein the heating has a duration of 5 minutes or more.

3 . The method for producing fluorenone according to claim 1 , wherein the mixture comprises fluorenone and bromide ions, and
wherein a concentration of the bromide ions in the mixture is 0.01 to 5 parts by mass relative to 100 parts by mass of fluorenone.

4 . The method for producing fluorenone according to claim 1 , wherein the distilling comprises, in the order indicated, removing a high boiling point component and removing a low boiling point component.

5 . The method for producing fluorenone according to claim 1 , wherein the metal catalyst is at least one selected from the group consisting of a cobalt catalyst, a manganese catalyst, a zirconium catalyst, a cerium catalyst, and a nickel catalyst.

6 . The method for producing fluorenone according to claim 1 , wherein the aliphatic carboxylic acid is acetic acid.

7 . The method for producing fluorenone according to claim 1 , wherein oxygen is supplied by introducing air during the oxidizing.

8 . The method for producing fluorenone according to claim 1 , wherein the temperature in the heating is in a range of 180 to 350° C.

9 . The method for producing fluorenone according to claim 1 , wherein the temperature in the heating is in a range of 220 to 350° C.

10 . The method for producing fluorenone according to claim 2 , wherein the temperature in the heating is in a range of 180 to 350° C.

11 . The method for producing fluorenone according to claim 3 , wherein the temperature in the heating is in a range of 180 to 350° C.

12 . The method for producing fluorenone according to claim 4 , wherein the temperature in the heating is in a range of 180 to 350° C.

13 . The method for producing fluorenone according to claim 7 , wherein the temperature in the heating is in a range of 180 to 350° C.

14 . The method for producing fluorenone according to claim 2 , wherein the temperature in the heating is in a range of 220 to 350° C.

15 . The method for producing fluorenone according to claim 3 , wherein the temperature in the heating is in a range of 220 to 350° C.

16 . The method for producing fluorenone according to claim 4 , wherein the temperature in the heating is in a range of 220 to 350° C.

17 . The method for producing fluorenone according to claim 7 , wherein the temperature in the heating is in a range of 220 to 350° C.

18 . The method for producing fluorenone according to claim 2 , wherein the mixture comprises a fluorenone ion and a bromide ion,
wherein a concentration of the bromide ion in the mixture is 0.01 to 5 parts by mass relative to 100 parts by mass of fluorenone, and wherein the temperature in the heating is in a range of 180 to 350° C.

19 . The method for producing fluorenone according to claim 18 , wherein the distilling comprises, in the order indicated, removing a high boiling point component and removing a low boiling point component.

20 . The method for producing fluorenone according to claim 14 , wherein the mixture comprises a fluorenone ion and a bromide ion,
wherein a concentration of the bromide ion in the mixture is 0.01 to 5 parts by mass relative to 100 parts by mass of fluorenone, and wherein the distilling comprises, in the order indicated, removing a high boiling point component and removing a low boiling point component.

Assignees

• Mitsubishi Gas Chemical Co

Inventors

• Sumi Hiroki
• Watanabe Yuki
• Fujita Hideaki
• Nakamura Goh
• Kumano Tatsuyuki

Classifications

• C07C45/82

  by distillation · CPC title

• C07C45/36 Primary

  in compounds containing six-membered aromatic rings · CPC title

• C07C2603/18

  Fluorenes; Hydrogenated fluorenes · CPC title

• B01J31/04

  containing carboxylic acids or their salts {(B01J31/0277 - B01J31/0298 take precedence; multi-metal carboxylate complexes like Pd (II) acetate, i.e. Pd3 (OAc) 6 or Cr(II)acetate, i.e. Cr2(OAc)4 B01J31/2226)} · CPC title

• C07C49/675 Primary

  having three rings · CPC title