JP3176098B2 - Method for producing bis (4-allyloxy-3,5-dibromophenyl) sulfone - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to bis (4-allyloxy-3,5-dibromophenyl) sulfone [hereinafter referred to as TB
[Abbreviated as S-BA] in an industrially advantageous process and at a high yield. T
BS-BA is useful as a flame retardant for a resin and as an intermediate for a flame retardant. In particular, bis (3,5-dibromo-4-) obtained by brominating an allyl group of TBS-BA is used.
(2,3-Dibromopropyloxy) phenyl) sulfone (hereinafter abbreviated as TBS-BP) is known to be extremely effective as a flame retardant such as polypropylene (Japanese Patent Publication No. 50-35103).

[0002]

2. Description of the Related Art Conventionally, as a method for producing TBS-BA,
Allyl bromide and bis (4-hydroxy-3,5-dibromophenyl) sulfone (hereinafter abbreviated as TBS) in a mixed solution of water and a lower alcohol or an ether-based water-soluble solvent in the presence of an alkali. Is known (Japanese Patent Publication No. 50-35103). further,
In connection with this production method, in order to improve the yield of TBS-BA, a method of dropping allyl bromide into the raw material system (Japanese Patent Application Laid-Open No. 3-11051), the ratio of a water-water-soluble organic solvent as a reaction solvent was adjusted. A method performed in a certain range (Japanese Unexamined Patent Application Publication No. 3-11052)
No. 2) and other improved methods are disclosed. Further, as a method for producing TBS-BA using an industrially inexpensive allyl chloride as a raw material, a production method in which KBr, NaBr, or the like is added as a catalyst to a raw material system to improve the yield has been disclosed (Japanese Patent Publication No. Sho 63). -39585). However, all of these production methods are carried out in a mixed solution of water and a water-soluble solvent such as a lower alcohol or an ether.
-Since BA is precipitated out of the system, a complicated filtration step is required during the production process. Also, the filtered TB
Since water is used for washing the S-BA, it takes a long time to dry. In addition, an organic solvent such as alcohol is mixed into the filtrate, so that waste liquid treatment or the like is required.

[0003] On the other hand, a reaction for the allyl etherification of bisphenol S in the presence of a certain quaternary ammonium salt under phase transfer conditions is known (JP- A- 61-1).
No. 37854). However, a highly lipophilic quaternary ammonium salt, such as trioctylmethylammonium chloride, which is described as being effective in allylating bisphenol S described in this patent, is considered by the present inventors to be useful in the allylation of TBS. When used as a phase transfer catalyst, the conversion was remarkably small, and it was found that there was no effect as a phase transfer catalyst. That is, 4 with high fat solubility
The quaternary ammonium salts are not effective in the allylation of TBS, and thus there has been no knowledge about a phase transfer catalyst exhibiting high activity for the allylation reaction under the phase transfer conditions of TBS.

[0004]

SUMMARY OF THE INVENTION An object of the present inventor is to provide a TB process without a complicated filtration step in an industrial process.
An object of the present invention is to provide a production method for obtaining S-BA in a high yield.

[0005]

Means for Solving the Problems In order to solve the above problems, the present inventors have intensively studied a phase transfer catalyst effective for allylation of TBS. As a result, the present inventors have surprisingly found that, unlike in the case of bisphenol S, the allylation of TBS, found that highly hydrophilic quaternary ammonium two <br/> um salt, is extremely effective Thus, the present invention has been completed. That is, the present invention provides bis- (4-hydroxy-3,5-dibromophenyl) sulfone and allyl halide as a phase transfer catalyst in the presence of water, an organic solvent incompatible with water, and an alkali, (1) a highly hydrophilic quaternary ammonium salt represented by (formula 2)

[0006]

Embedded image (Wherein R ₁ , R ₂ , R ₃ and R ₄ each independently represent a benzyl group or an alkyl group having 4 or less carbon atoms , and X represents Cl, Br or HSO ₄ ),
Bis (4-allyloxy-3,5) for etherification
- dibromophenyl) a method for producing a sulfone, further, in formula (1), X is related the method of production using the quaternary ammonium salt is Br or HSO _4.

[0007] Quaternary A of the formula (1) used in the present invention
Nmo salts are highly hydrophilic quaternary ammonium salts, more particularly, each of the substituents, quaternary ammonium Niu <br/> unsalted a benzyl group or an alkyl group having 4 or less carbon atoms It is. Such highly hydrophilic quaternary ammonium salts, for the allylation of bisphenol S, not effective at all, for example, when using benzyltriethylammonium chloride as a phase transfer catalyst, the yield of diallyl ether be low There has been described in JP 61 No. -137854. However, in TBS, the ortho-position of the hydroxyl group in the molecular structure is Br, which is an electron-withdrawing group.
Since it is substituted by an atom, the acidity is higher than that of bisphenol S.
The allylation reaction of S is greatly different from that of bisphenol S, and occurs mainly in the aqueous layer and has a high hydrophilicity.
It was found that grade ammonium salt is effective.

[0008] Specific examples of the highly hydrophilic quaternary ammonium two <br/> ium salt used in the present invention, tetramethylammonium chloride, tetraethylammonium chloride, tetrabutylammonium chloride, benzyltrimethylammonium chloride, benzyltriethylammonium chloride , Benzyltributylammonium chloride, tetramethylammonium bromide, tetraethylammonium bromide, tetrabutylammonium bromide, benzyltrimethylammonium bromide, benzyltriethylammonium bromide,
Benzyltributylammonium bromide, tetramethylammonium hydrosulfate, tetraethylammonium hydrosulfate, tetrabutylammonium hydrosulfate, benzyltrimethylammonium hydrosulfate, benzyltriethylammonium hydrosulfate, benzyltributylammonium hydrosulfate , and the like . The amount of the quaternary ammonium salt is 1 to 50 mol% relative to the TBS of the raw material, preferably 2 to 30 mol%.

[0009] The reaction of the present invention is carried out in a mixed solution of water and an organic solvent. The amount of water used is 300-3500 ml per 1 mol of TBS. The organic solvent used in the present invention is not particularly limited as long as it is incompatible with water, and is not particularly limited as long as it is inactive with respect to the raw material system. Benzene, toluene, aromatic hydrocarbons such as xylene, Halogenated aromatic hydrocarbons such as chlorobenzene, hexane,
Examples include hydrocarbons such as heptane and cyclohexane, halogenated hydrocarbons such as dichloromethane, chloroform, dichloroethane, trichloroethane and tetrachloroethane, water-insoluble ethers such as dibutyl ether, and water-insoluble ketones such as methyl isobutyl ketone and diisobutyl ketone. . The amount of the organic solvent used is 500 to 3000 ml per 1 mol of TBS. The usage ratio of water and the organic solvent is water: organic solvent = 1: 0.5 to 2 by volume ratio.

As the allyl halide used in the present invention, allyl chloride is preferred from the viewpoint of cost and the like, but use of allyl bromide does not impose any problem. The amount may be at least twice the molar amount of TBS, and preferably 2 to 3 times the molar amount in view of the complexity of post-treatment and the like. Examples of the alkali used in the present invention include hydroxides, carbonates and bicarbonates of alkali metals, and sodium hydroxide is preferred from the viewpoint of cost and the like. The amount of the alkali used is at least 2 times mol, preferably 2 to 4 times mol, of TBS.

[0011] the production method of the present invention, a TBS and allyl halides, water, an organic solvent, a method of reacting in the presence of alkali and a quaternary ammonium Niu <br/> unsalted. The reaction temperature ranges from room temperature to 150 ° C, preferably from 60 to 120 ° C. When the reaction temperature is higher than the boiling point of the solvent, a closed reaction vessel such as an autoclave may be used. The reaction is carried out by heating and stirring at a predetermined reaction temperature for 1 to 15 hours, and the progress of the reaction can be monitored using, for example, an analytical instrument such as high performance liquid chromatography.

[0012] After completion of the reaction, the product in an organic layer, an inorganic salt is included in the aqueous layer, quaternary ammonium salts are distributed into an organic layer and an aqueous layer in accordance with its hydrophilicity. After separation of the aqueous layer, by further washing the organic layer, it is possible to remove the quaternary ammonium salts of the organic layer. Unreacted TBS remaining in the organic layer in a trace amount can be removed by washing the organic layer with an aqueous alkaline solution. Depending on the organic solvent used, when cooled to near room temperature, the generated TBS-BA may precipitate.
In such a case, there is no problem even if the washing and liquid separation steps are performed under heating. By removing the organic solvent from the organic layer obtained after the washing step, TB
S-BA is obtained with high purity.

[0013]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto. Example 1 A four-necked flask equipped with a thermometer, a reflux condenser, and a stirrer was charged with 360 ml of water, and 17.1 g of NaOH (0.1 mL) was added.
43 mol) and 113 g (0.2 mol) of TBS were added and dissolved. Then, 1,1,2-trichloroethane 30
0 ml, benzyltri-n-butylammonium bromide 14 g (0.016 mol), allyl chloride 39
g (0.51 mol), and then heated to 90 ° C. while stirring.
For 7 hours. After 7 hours, the conversion to TBS-BA was 95% as measured by high performance liquid chromatography. After the reaction was completed, the organic layer was separated and washed with water. Further, the organic layer was washed with a 5% aqueous NaOH solution and then again with water. Then, the solvent of the organic layer was distilled off, and the obtained solid was dried under reduced pressure at 80 ° C./10 mmHg to obtain TBS-BA, which was a target substance. Yield 116.2
g, yield was 90.0%.

Example 2 A four-necked flask equipped with a thermometer, a reflux condenser, and a stirrer was charged with 360 ml of water, and 17.1 g of NaOH (0.1 mL) was added.
43 mol) and 113 g (0.2 mol) of TBS were added and dissolved. Then, 300 ml of chlorobenzene and 13 g of tetra-n-propylammonium bromide (0.0 g
49 mol), 39 g (0.51 mol) of allyl chloride
, And the mixture was heated under stirring and reacted at 90 ° C. for 7 hours. After 7 hours, the conversion to TBS-BA was 92%. After the reaction was completed, the organic layer was separated and washed with water. Further, the organic layer was washed with a 5% aqueous NaOH solution and then again with water. When chlorobenzene was used, the intended product was precipitated at room temperature, so washing and liquid separation were performed under heating at 60 ° C.
Next, the solvent of the organic layer was distilled off, and the obtained solid was heated to 80 ° C.
By drying under reduced pressure at / 10 mmHg, TBS-BA, which was the target substance, was obtained. The yield is 114.0 g and the yield is 8
It was 8.3%.

Example 3 In Example 2, diisobutyl ketone, 4
Using benzyltriethylammonium hydroxide sulfate as grade ammonium salt, the reaction was carried out in the same manner as in Example 2. The washing liquid separation step was performed under heating at 60 ° C.
The conversion after the completion of the reaction was 92%. The yield is 111.
8 g, the yield was 86.5%.

[0016] In Comparative Example 1 Example 1, instead of a quaternary ammonium salt in trioctylmethylammonium chloride, The reaction was conducted under the same conditions as in Example 1, the conversion rate was 40%. Comparative Example 2 In Example 1, KBr was used without using a phase transfer catalyst.
When the reaction was carried out using as a catalyst, the conversion was 45
%Met.

[0017]

Industrial Applicability According to the present invention, in a process for producing TBS-BA, a filtration step, which has been industrially complicated so far, is omitted, so that TBS-BA having high cost and high purity can be produced. It became possible to provide.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-62-10058 (JP, A) JP-A-61-137854 (JP, A) JP-A-3-38563 (JP, A) JP-A-4- 91072 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C07C 317/00 C07C 315/00 CA (STN) REGISTRY (STN)

Claims (2)

(57) [Claims] 1. Bis- (4-hydroxy-3,5-dibromophenyl) sulfone and allyl halide are mixed with water, water
As a phase transfer catalyst in the presence of an organic solvent and an alkali that are not compatible with the hydrophilic solvent represented by the formula (1)
High quaternary ammonium salt [Formula 1] (Wherein R ₁ , R ₂ , R ₃ and R ₄ each independently represent a benzyl group or an alkyl group having 4 or less carbon atoms , and X represents Cl, Br or HSO ₄ ) Bis (4-characterized by etherification reaction)
A method for producing (allyloxy-3,5-dibromophenyl) sulfone. 2. A quaternary ammonium salt has the formula (1) odor <br/> Te, X is according to claim 1, wherein the compound represented by Br or HSO ₄ bis (4-allyloxy-3,5 -Dibromophenyl) sulfone production process.