Preparation method for 4-phenylthio-benzenethiol

Patent metadata

Field	Value
Publication number	US-11220478-B2
Application number	US-201816955511-A
Country	US
Kind code	B2
Filing date	Jul 12, 2018
Priority date	Dec 22, 2017
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

The present disclosure discloses a preparation method for 4-phenylthio-benzenethiol. The preparation method comprises the following steps: subjecting phenyl sulfide as a raw material to a halogenation reaction to obtain 4-halophenyl sulfide; subjecting the 4-halophenyl sulfide to a sulfhydrylation reaction to obtain a 4-phenylthio-phenylthiolate; and subjecting the 4-phenylthio-phenylthiolate to acidification. The preparation method of the present disclosure avoids the use of materials such as thiophenol which pollutes the environment, and realizes efficient recycling of the reaction materials, solvents, water and the like. The preparation method of the present disclosure is a green process for the synthesis of 4-phenylthio-phenylthiol without organic waste, waste acid and waste water discharge.

First claim

What is claimed is:

1. A preparation method for 4-phenylthio-benzenethiol, comprising the steps of:
subjecting phenyl sulfide as a raw material to a halogenation reaction to obtain 4-halophenyl sulfide;
subjecting the 4-halophenyl sulfide to a sulfhydrylation reaction to obtain 4-phenylthio-phenylthiolate; and
subjecting the 4-phenylthio-phenylthiolate to acidification;
wherein
the halogenation reaction is: adding peroxide to a mixed solution containing phenyl sulfide, an organic solvent, a halogenating agent, and an inorganic acid to undergo a halogenation reaction, and obtaining 4-halophenyl sulfide by separation;
the sulfhydrylation reaction is: subjecting the resulting 4-halophenyl sulfide and a SMAB-NaHS complex to a sulfhydrylation reaction, and obtaining an aqueous layer containing 4-phenylthio-phenylthiolate by extraction and separation; and
the acidification reaction is: subjecting the aqueous layer containing 4-phenylthio-phenylthiolate to an acidification reaction in an acidic aqueous solution, and obtaining the 4-phenylthio-benzenethiol by separation.

2. The preparation method according to claim 1 , wherein, in the halogenation reaction,
the halogenating agent is one or more selected from the group consisting of sodium bromide and potassium bromide;
the inorganic acid is one or more selected from the group consisting of sulfuric acid, hydrochloric acid, and phosphoric acid;
based on 1 mol of phenyl sulfide, an amount of the halogenating agent is from 0.9 to 1.0 mol; and an amount of the inorganic acid is from 0.9 to 1.0 mol.

3. The preparation method according to claim 1 , wherein, in the halogenation reaction,
the organic solvent is one or more selected from the group consisting of dichloromethane, chloroform, carbon tetrachloride, and dichloroethane;
based on 1 mol of phenyl sulfide, an amount of the organic solvent is from 4 to 6 mol.

4. The preparation method according to claim 1 , wherein, in the halogenation reaction,
the peroxide is hydrogen peroxide;
an amount of the peroxide is from 0.45 to 0.5 mol based on 1 mol of phenyl sulfide; and
the time of adding the peroxide is controlled at 2 to 10 hours, and the peroxide is added dropwise.

5. The preparation method according to claim 1 , wherein,
in the halogenation reaction, the temperature for the halogenation reaction is from 10° C. to 40° C., and a total reaction time is from 4 to 15 hours.

6. The preparation method according to claim 1 , wherein,
in the sulfhydrylation reaction, based on 1 mol of phenyl sulfide, an amount of the SMAB-NaHS complex is from 0.9 to 1.0 mol .

7. The preparation method according to claim 1 , wherein, in the sulfhydrylation reaction, the SMAB-NaHS complex is prepared by the following method:
a. adding a sodium hydroxide aqueous solution to an NMP solvent, and after the reaction is completed, subjecting the reactant to dehydration; and
b. adding a sodium hydrosulfide aqueous solution prior to dehydration to obtain a SMAB- NaHS complex.

8. The preparation method according to claim 7 , wherein,
based on 1 mol of phenyl sulfide, an amount of the sodium hydroxide is from 0.9 to 1.0 mol; an amount of the NMP solvent is from 4.0 to 5.0 mol; and an amount of the sodium hydrosulfide is from 0.9 to 1.0 mol.

9. The preparation method according to claim 7 , wherein the dehydration in steps a and b is carried out at 180° C. to 250° C.

10. The preparation method according to claim 1 , wherein,
the sulfhydrylation reaction is carried out at 150° C. to 230° C.; and the time of the sulfhydrylation reaction is 3 to 6 hours.

11. The preparation method according to claim 1 , wherein,
after the sulfhydrylation reaction is completed, desolvation is performed prior to extraction and separation; and
NMP recycled by desolvation is capble of being directly used for the preparation of a SMAB-NaHS complex.

12. The preparation method according to claim 1 , wherein,
after the halogenation reaction is completed, an aqueous layer and an organic layer are obtained by separation; where
the aqueous layer is used as an acidic aqueous solution in the acidification reaction; and
the organic layer is desolventized and recycled to obtain a solvent, to which water is added, for use in extraction carried out following the sulfhydrylation reaction.

13. The preparation method according to claim 12 , wherein an organic layer obtained by extraction and separation after the sulfhydrylation reaction is used as a solvent in the halogenation reaction.

14. The preparation method according to claim 1 , wherein,
delamination is performed following the acidification reaction;
the resulting aqueous layer is subjected to cooling crystallization to give Na 2 SO 4 containing crystal water; and
the remaining mother solution is concentrated and then used as a raw material for the halogenation reaction.

15. The preparation method according to claim 1 , wherein,
based on 1 mol of phenyl sulfide, an amount of the halogenating agent is from 0.95 to 0.99 mol; and an amount of the inorganic acid is from 0.95 to 0.99 mol.

16. The preparation method according to claim 6 , wherein,
in the sulfhydrylation reaction, based on 1 mol of phenyl sulfide, an amount of the SMAB-NaHS complex is from 0.95 to 0.99 mol.

17. The preparation method according to claim 1 , wherein, the sulfhydrylation reaction is carried out at 150° C. to 230° C.; and the time of the sulfhydrylation reaction is 3 to 6 hours.

18. The preparation method according to claim 1 , wherein, the sulfhydrylation reaction is carried out at 180° C. to 210° C.

19. The preparation method according to claim 1 , wherein, the sulfhydrylation reaction is carried out at 180° C. to 210° C.

Assignees

• Zhejiang Nhu Co Ltd
• Univ Zhejiang
• Zhejiang Nhu Special Mat Co Ltd

Inventors

• Chen Zhirong
• Li Woyuan
• Yin Hong
• Zhou Guíyang
• Li Haoran
• Pan Shuaifeng
• Lian Ming
• Qin Guangde
• Li Qichuan

Classifications

• C07C319/20 Primary

  by reactions not involving the formation of sulfide groups · CPC title

• C01D5/02

  Preparation of sulfates from alkali metal salts and sulfuric acid or bisulfates; Preparation of bisulfates · CPC title

• C07C323/09

  having sulfur atoms of thio groups bound to carbon atoms of six-membered aromatic rings of the carbon skeleton · CPC title

• C07C321/30

  Sulfides having the sulfur atom of at least one thio group bound to two carbon atoms of six-membered aromatic rings · CPC title