JPH0782207A - Production of fluorenone and oxidation catalyst used therein - Google Patents

Abstract

PURPOSE:To permit the efficient production of fluorenone of high purity from fluorene with no formation of by-products using a specific amine derivative as an oxidation catalyst economically in a shortened time. CONSTITUTION:To 2.5 to 30wt.% fluorene solution, is added 35 to 50wt.% of alkali aqueous solution and a catalyst aqueous solution. Then, oxygen is introduced into the mixture in an amount of 1.0 to 1.5 mole per mole of the fluorene. As the oxidation catalyst, is used an aqueous solution of 30 to 70wt.% concentration of one or more amine derivatives of the formula I (R<1> is H, lower alkyl; R<2> is lower alkyl; a is 1 to 2; X is SO4<-->, CH3SO4<--> where when X is SO4<-->, a=2; when X is CH3SO4<-->, a=1), particularly N,N-dimethylaniline is preferred). The catalyst is obtained, for example, by mixing N,N-dimethylaniline with dimethyl sulfate, stirring the mixture at room temperature, admixing water thereto, dripping IN sodium hydroxide until the pH reaches 7, filtering off the precipitate and adding water to the filtrate.

Description

Detailed Description of the Invention

FIELD OF THE INVENTION The present invention relates to a method for producing fluorenone and an oxidation catalyst used therein.

As a method for producing fluorenone by oxidizing fluorene, a method of dissolving fluorene in a water-soluble organic solvent such as acetic acid and oxidizing it with an aqueous sodium dichromate solution (Org. Syn., Coll. vol 3
p. 838) and fluorene are dissolved in benzene or the like, an aqueous alkali solution is added, and air oxidation is performed in the presence of an oxidation catalyst such as dicetyldiethylammonium chloride or tetraethylammonium hydroxide (Te
trahedron Lett. , No24, pp21
17-2118, 1977) is known.

[Problems to be Solved by the Invention] However, in the conventional oxidation of fluorene with sodium dichromate, a polymer is produced as a by-product and it is necessary to remove it. In addition, fluorene is oxidized by air in the presence of an oxidation catalyst. This method also has a problem that the oxidation catalyst is decomposed due to the concentrated alkaline aqueous solution. The present inventors have conducted extensive studies in order to solve the above-mentioned problems in producing fluorenone from fluorene, and as a result, have shown the formula [R ¹ C ₆ H ₄ N ⁺ (R ² ) ₃ ] _a X
(In the formula, R ¹ is a hydrogen atom or a lower alkyl group, R ² is a lower alkyl group, a is an integer of 1 or 2, X is SO ₄ ⁻ or CH ₃ SO ₄ ⁻ , where a is X is SO ₄ ^{− −.} 2 and X is 1 when X is CH ₃ SO ₄ ⁻ ) and 3 of a mixture of one or two amine derivatives having a composition represented by
The present invention was completed by finding that fluorenone can be quantitatively produced without producing a by-product by introducing 1.0 to 15 times mol of oxygen with respect to fluorene by using a 0 to 70% by weight aqueous solution as an oxidation catalyst. Came to do.

BRIEF SUMMARY OF THE INVENTION Namely, the present invention is 35 to 50 wt% alkaline aqueous solution of the general formula in 2.5 to 30 wt.% Solution of fluorene _{^{[R 1 C 6 H 4 N}} + (R 2) 3] a
X (in the formula, R ¹ is a hydrogen atom or a lower alkyl group, R ² is a lower alkyl group, a is an integer of 1 or 2, X is SO ₄ ⁻⁻ or CH ₃ SO ₄ ⁻ , where a is X and SO ₄ ^{−. -} when the 2, X is CH ₃ SO ₄ ^- 3 of one or two of the mixture of the amine derivative having a composition is represented by a is 1) when
A method for producing fluorenone, which comprises adding an oxidation catalyst consisting of an aqueous solution of 0 to 70% by weight to introduce oxygen in an amount of 1.0 to 15 times the molar amount of fluorene, and a fluorenone consisting of an aqueous solution of an amine derivative to be used in the same Is an oxidation catalyst used in the production of

EXAMPLES Examples of alkaline aqueous solutions used in the method for producing fluorenone of the present invention include NaOH, KOH, and Ca (OH).
A solution in which an alkali metal such as ₂ is dissolved in water is used. From the viewpoint of reaction time and economy, the concentration of the alkali metal is usually preferably 35 to 50% by weight, and further 40
More preferably, it is ˜48% by weight. The concentration of the fluorene solution used in the present invention is 2.5 to 30% by weight.
When the concentration of fluorene deviates from the above range, there are problems that unreacted fluorene is recovered and a large amount of solvent is used, resulting in poor economy. The solvent used for preparing the fluorene solution used in the present invention is, for example, a solvent insoluble in water such as benzene, toluene, ethylbenzene, chloroform and aromatic amine, which dissolves fluorene and removes the solvent from the reaction solution. It is preferable from the viewpoint of economic efficiency such as recovery, more preferable is toluene, ethylbenzene, aromatic amine from the viewpoint of working environment, and N, N-dimethylaniline among aromatic amines is preferable from the viewpoint of safety during reaction. (Hereinafter referred to as DMA) is particularly preferable. The general formula used in the present invention [R ¹ C ₆ H ₄ N ⁺
30-70 of ^(R _{2) 3]} amine derivative represented by _a X
The oxidation catalyst composed of a wt% aqueous solution is, for example, C ₆ H ₅ N
It is prepared by reacting (CH ₃ ) ₂ with (CH ₃ ) ₂ SO _{4 in} a molar ratio of 1: 1 to 2: 1 and adding water.
The oxidation catalyst is preferably an aqueous solution having an amine derivative concentration of 30 to 70% by weight. Amine derivative concentration is 3
When it is less than 0% by weight, the action as an oxidation catalyst is weak and fluorene is not quantitatively oxidized, and when it exceeds 70% by weight, the viscosity increases and it is difficult to mix it uniformly with a fluorene solution. There are problems such as The amount of the alkaline aqueous solution used in the present invention is 0.1 to 20 parts by weight with respect to fluorene. When the amount of the alkaline aqueous solution is less than 0.1 parts by weight, the reaction rate is slow, and when it exceeds 20 parts by weight, there are problems such as economical efficiency and generation of by-products. The amount of the amine derivative aqueous solution which is the oxidation catalyst used in the present invention is 0.1 to 30 parts by weight with respect to fluorene. If the amount of the amine derivative aqueous solution deviates from the above range, there are problems such as a decrease in yield and generation of by-products. The amount of oxygen introduced in the present invention is usually preferably 1.0 to 15 times the molar amount of fluorene. When the amount of oxygen introduced is less than 1.0 times the molar amount, there is a large amount of unreacted fluorene, and when the amount exceeds 15 times the molar amount, the organic solvent is evaporated. Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to the examples. Example 1 Fluorene 1 in a 300 ml three-necked flask
6.6 g (0.1 mol) was added and dissolved with 175 g of toluene, and 43.8 g of 48% aqueous alkali solution and [C ₆ H ₅ N
⁺ _{(CH 3) 3]} 50 of 2 SO ₄ wt% aqueous solution of 3.2g
And while introducing air at 0.8 liter / min. 3
Stir for hours. After the stirring was completed and the mixture was allowed to stand, the toluene layer was separated and the toluene was distilled off to obtain yellow crystals of fluorenone. Yield 14.9 g (yield 92.2%) Melting point: 81.
2-83. ° C purity 100% (gas chromatographic analysis method: column used Shimadzu CBP10-M25-025) (Example 2) 175 g of 48% alkaline aqueous solution, [C ₆
Fluorenone was obtained in the same manner as in Example 1 except that 25 g of a 50 wt% aqueous solution of H ₅ N ⁺ (CH ₃ ) ₃ ] ₂ SO ₄ was used. Yield 16.9 g (93.9% yield) (Example ^{_{3) [C 6 H 5 N}} + (CH 3) 3] instead of 50 wt% aqueous solution of ^{_{2 SO 4 [C 6 H 5}} N + (CH ₃ )
₃ ] Fluorenone was obtained in the same manner as in Example 1 except that a 30% aqueous solution of MeSO ₄ was used. Yield 14.0 g (yield 90.0%) (Examples 4 to 7) DMA was used as a solvent for the fluorene solution, and fluorenone was synthesized from fluorene under the conditions shown in Table 1. The results are shown in Table 1. Example 8 Synthesis of Oxidation Catalyst 12.6 g (0.1 mol) of C ₆ H ₅ N (CH ₃ ) ₂ and 13.8 g (0.11 mol) of (CH ₃ ) ₂ SO ₄ were mixed to give 1 After stirring at room temperature for 12 hours, 12 g of water was added. Then, 0.1N sodium hydroxide was added dropwise until the pH reached 7, the precipitate formed was filtered off, and 12 g of water was added to obtain an oxidation catalyst consisting of a 50% by weight aqueous solution.

EFFECTS OF THE INVENTION According to the method for producing fluorenone of the present invention, fluorenone having high purity can be efficiently synthesized economically in a short time without any by-products.

Claims (5)

[Claims] 1. A 2.5 to 30 wt% solution of fluorene in an aqueous solution of 35 to 50 wt% and a general formula [R ¹ C ₆
H ₄ N ⁺ (R ² ) ₃ ] _a X (wherein R ¹ is a hydrogen atom or a lower alkyl group, R ² is a lower alkyl group, a is an integer of 1 to 2, X is SO ₄ ⁻ or CH ₃ SO _{3. 4} ^-, where a is X
Oxide consisting of 30 to 70% by weight aqueous solution of one or two of the mixture of the amine derivative having a composition is represented by a is 1) when the ^- but _SO ^{4 -} 2, X is _CH 3 SO ₄ when the Add a catalyst and add oxygen to fluorene 1.0 to 15
A method for producing fluorenone, which comprises introducing a double molar amount. 2. An alkali aqueous solution of 0.1 to 20 parts by weight and an amine derivative aqueous solution of 0.1 to 3 with respect to fluorene.
The method for producing fluorenone according to claim 1, which is part by weight. 3. The method for producing fluorenone according to claim 2, wherein the solvent of the fluorene solution is an aromatic amine. 4. The method for producing fluorenone according to claim 3, wherein the aromatic amine is N, N-dimethylaniline. 5. The general formula [R ¹ C ₆ H ₄ N
⁺ (R ² ) ₃ ] _a X (wherein R ¹ is a hydrogen atom or a lower alkyl group, R ² is a lower alkyl group, a is an integer of 1-2, X
Is SO ₄ ⁻⁻ or CH ₃ SO ₄ ⁻ , where a is X is SO.
₄ ^- is 2, X is _CH 3 SO ₄ when the ^- production of fluorenone consisting of 30 to 70% by weight aqueous solution of one or two of the mixture of the amine derivative having a composition is represented by a 1) when Oxidation catalyst used for.