JPS62158243A - Production of alpha-naphthylacetic acid - Google Patents

Abstract

PURPOSE:To obtain the titled compound useful as a plant growth inhibitor, safely in high yield without necessitating expensive apparatus and distillation process, etc., with simple extraction and decoloration process, etc., by subjecting naphthalene, etc., to chloromethylation and carbonylation followed by concentration, extraction, hydrolysis, etc. CONSTITUTION:According to the process shown in the reaction formula, naphthalene is made to react with formaldehyde and hydrochloric acid in the presence of an acid catalyst to obtain a solution containing alpha-chloromethylnaphthalene. The solution is made to react with carbon monoxide, a basic substance and an alcohol in the presence of cobalt carbonyl catalyst while continuously adding the catalyst, etc., to the reaction system without separating the solution from the system. The catalyst in the produced solution of a naphthylacetic acid ester is decomposed by the treatment with an acid and oxygen and excessive alcohol is distilled out. The resultant concentrated liquid is added with water, etc., to extract the alpha-naphthylacetic acid ester to an organic layer and the cobalt compound to an aqueous layer. The organic layer is hydrolyzed, pH of the obtained liquid is adjusted, the by-product is extracted at >=6.5pH, the liquid is decolored under nearly neutral condition and the objective compound is crystallized at 1.5-3.0pH. The precipitated compound is washed with water, dried and purified.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides α-naphthyl 0#! This invention relates to an industrially advantageous manufacturing method for 7L.

[Industrial application field]

α-naphthyl vinegar l! It is known as #12 Ha, #L biomass hormone, and its main uses are as an agent for promoting the growth of plants in exhibition rooms.

1. A method for producing naphthalene by chloromethylation, cyanation, and hydrolysis. (Kogakuin Oaza Kenjuho Tongue 2 60
~65 (1955), Przemyslchem
, 9, 463-4 (1955)) 2. Reaction of naphthalene with acetic anhydride (Chem, B6r.

8L], 410-412 (1947)) 6, Reaction of naphthalene with monochlor O' modified (F'ert.

Technol, 17 (1-2), 80-82 (
198LI).

Organic Synthesis Journal, 18, 198-202, (1960
) etc.) etc. are known.

4. Method for producing α-naphthyl acetic acid methyl ester by carbonylation of α-chloromethylnaphthalene (Japanese Patent Publication No. 59-21852, Japanese Patent Publication No. 59-21852, Japanese Patent Publication No. 59-21852, Japanese Patent Publication No. Sho!:) 6-4L1
No. 144) is known.

[Problems that the invention attempts to address] 1. The method includes a step of distilling α-chloromethylnaphthalene, and α-chloromethylnaphthalene is a dermatological substance. − is required. 17'c,
During cyanation, there is a problem with femininity due to the use of excessive T-relatives, which tends to produce cut-off particles, which makes the refining process difficult, and the overall yield is low at 6 to 4 U%.

2.0 method μ, the selectivity is about 70%, but the reaction rate is 2
It's arrogant, low and impractical.

In method 6, the conditions are difficult as the reaction rate is 2 LlO"c or more, and the yield is low at 20 to 60%.

In the carbonylation method of 4, pure α-chloromethylnaphthalene is used, but the same 1fJR method as in method (1) is used.
IF has 4 holes and evaporation under high vacuum is required, which increases equipment costs, and when reacting by charging α-chloromethylnaphthalene and other raw materials all at once, a low part ratio is required. Only the results obtained are obtained, and further due to carbonylation!
It is not possible to obtain pure α-naphthyl acetic acid from the obtained tα-naphthyl acetic acid dister.

In the present invention, naphthalene, formalin or formaldehyde and hydrochloric acid are used in the presence of mineral acids as catalysts at a temperature of 7 U.
a chloromethylation step in which the α-chloromethylnaphthalene-containing solution is reacted with α-chloromethylnaphthalene in a bath liquid containing α-chloromethylnaphthalene; Presence of cobalt carbonyl catalyst 1', -[carbonyl, basicity'$!J
a step of continuously adding α-chloromethylnaphthalene or a catalyst to obtain a naphthyl acetate bath solution in the carbonylation step of reacting cobalt carbonyl and alcohol; (3) cobalt carbonyl in the naphthyl acetate solution; a catalytic decomposition step of treating the goose medium with acid and oxygen; (4) a concentration step of distilling off excess alcohol in the product liquid of the M-medium decomposition step; (5) adding water or water to the concentrated liquid obtained in the concentration step. Step of mixing 121 t of water and tsukudade d agent, separating into an organic layer and an aqueous layer, and discharging α-naphthyl acetate from the organic layer and a cobalt compound t-ts from water, (6) the previous day. α-naphthyl ester modified from r2 Tsukuda excavated ester tMmuM
A step of converting the water into distilled water or using an alkali to waterly decompose the water obtained in the above hydrolysis step...6.
5 or more and remove the by-product with a water-insoluble Miso bath medium,
Blend the - to near neutrality and decolorize it, then pl(el,!b
~5. L]KAjmt, 4-naphthyl acetic acid is crystallized and the inorganic r! in α-naphthyl acetic acid is crystallized. This is a method for producing α-naphthyl acetic acid, which consists of a purification process in which L is washed with water and dried.

According to the present invention, the manufacturing process is shorter than that of conventional manufacturing methods, and high-purity agitation can be obtained through the quantitative steps of extraction and decolorization without using the steamed im4 purification process. rate is high.

Equation 6 of each step is shown below.

Each step will be fully explained in detail.

1 to chemical itm1 to naphthalene to maldehyde
．． 2 to 2.0 fflJ1 imaginary is sufficient. Salt is filtration is chemical Jimlk's 6~7+f for naphthalene! Good quantity. There are no restrictions on the acid catalyst, but mineral acids, chain acids, phosphoric acid, hydrogen chloride, etc. are preferred.

The reaction temperature is 70'C to 100''C. If it is too low, the reaction rate is slow, and if it is too high, a slag product is likely to be produced.

After the reaction, the reaction gt-separates into two layers.

The M machine layer is washed with an alkaline water bath to remove acid content.

When to use alkaline? ttlJ unlimited force t1 charcoal changer, arashi- is preferable.

10,000, no water, too much salt! It is an advantage to recycle and use it in the red reaction in order to enrich it and reduce costs.

The raw chloromethylnaphthalene in the process of production is used without purification. The cobalt carbonyl catalyst used in the reaction is a salt of cobalt octacarbonyl or cobalt hydrocarbonyl, and preferably 11. < is Cδ(Co)
4 bath liquid.

The present inventors have already proposed a method for producing 06(Co)4 fg in Japanese Patent Publications No. 1987-27845 and t# Publication No. 55-54068.

Alcohol muff according to these? : is obtained by reacting a cobalt compound (for example, cobalt hydroxide, cobalt carbonate, hydrate or anhydride of cobalt acetate, etc.) with carbon monoxide and hydrogen in a polar medium such as acetate. Furthermore, if 46 g of Cδ(Co) is used as the I1 catalyst, the conditions will be relaxed to about 1@, and production can be performed at lower temperatures and pressures than in the past. The molar ratio of catalyst and α-chloromethylnaphthalene is 1:1.
400 is preferable, and 1:4 to 1:10U is preferable.
Yes.

There are no restrictions on the buttocks as long as alcohol rj and aliphatic alcohols are used, but methanol, ethanol,
Examples include inglopanol and n-butanol.

A basic substance* has a norodened water system t() produced as a by-product in the reaction.
! For example, ammonia, hydrazine, and aliphatic, aromatic primary, secondary, and tertiary amines. and metal alcoholades of aromatic alcohols, strong alkali metals; carbonates of alkaline earth metals, summer carbonates, enemy compounds; hydric compounds, and other known compounds are used.

The reaction temperature is 60-100°C, preferably 40-70'O
It is. The reaction pressure is preferably 2 to 50 g/cm, preferably 9 to 60 g/cm.

The carbon monoxide we use does not need to be of high purity;
Even if hydrogen and an inert gas are used together, the yield will not be low.

In the method of the present invention, the base used is a compound that easily reacts with the raw material α-chloromethylnaphthalene, such as
In the case of alcoholade, ammonia, and caustic soda, the reaction is carried out by branching into the base little by little. There are no limitations when using other bases.

The important point about carbonylation equipment is that when crude α-chloromethylnaphthalene is used as in the present invention, the raw material crude α-chloromethylnaphthalene, alcohol, basic substance, and shielding medium are all viscous. The method of reacting by circulating carbon monoxide after charging had a major problem in that both the reaction rate and selectivity were low, resulting in low yields.However, after extensive investigation, the inventors of the present invention found that it was possible to react by introducing other raw materials. By the way,
It has been found that α-naphthyl acetic acid ester can be obtained in high yield by continuously adding crude α-chloromethylnaphthalene or a catalyst.

After the carbonylation reaction, l! In the Itts decomposition step, the cobalt pentagonist is decomposed in the reaction solution using acid and oxygen.

The acids used are mineral acids and organic acids, and are not particularly limited, but sulfuric acid or hydrochloric acid is preferred.

The amount of acid used is 1.
It is 5 to 7 times the mole. The oxygen used may be pure oxygen, but preferably it may be diluted with a non-oily gas. Oxygen (11) is used in an amount equal to or more than the same mole relative to the cobalt carbonyl catalyst.

Although it is possible to decompose the catalyst using oxygen or acid alone, the decomposition proceeds in a short period of time when used in combination.

)'I! It medium decomposition temperature is 0 to 80'O, preferably 1
0 to 70°C @ Condensation Step In the concentration step, excess low-boiling compounds such as alcohol are distilled off and concentrated.

Creation Step In the extraction step, water is added to the concentrated solution for extraction, and α-naphthyl acetate is extracted from the aqueous layer, and the cobalt compound and the salt to be created are extracted from the aqueous layer.

Regarding the amount of water used in the extraction step, it is preferable for chestnut operation that the amount of water used be greater than the solubility of the salt, since a uniform bath solution can be used in the subsequent steps. In addition to water and alcohol, aromatic hydrocarbons such as toluene and benzene, and aliphatic hydrocarbons such as n-hexane and cyclohexane may be used as the depressant.

0.1 to 6 times the stoichiometric amount of alkali or acid to the extracted α-naphthyl acetate, preferably 1.5 times the stoichiometric amount.
Add an aqueous solution containing ~2.0 times as much water. There are no restrictions on acids and alkalis, but hydrochloric acid and sulfuric acid are preferable for acids, and caustic soda and caustic potash are preferable for alkalis.

The reaction is carried out with heating. Under reduced pressure, alcohol t-
It is more effective to carry out the reaction while distilling it off as it can shorten the hydrolysis time.

Although pi''1 of the hydrolyzed solution in the purification process is acidic or alkaline, highly pure α-naphthyl acetic acid cannot be obtained by simply crystallizing the PI'1t-94 node.

The Ministry of the Invention and others conducted extensive research on purification methods from hydrolyzate and found a method for obtaining highly pure α-naphthyl acetic acid by the following method.

That is, - of the hydrolyzed solution obtained in the above step is -6,
5 or more [Adding an organic solvent that is insoluble to water There is no restriction on bamboo as long as the organic solvent is insoluble in water, but last issue Haruka Hato~
Aromatic compounds such as toluene, benzene, and xylene; ethers such as diethyl ether and diisopropyl ether;
Stiryl compounds such as ethyl acetate are preferred.

Next, for the decolorization step, activated carbon or adsorbent resin is preferable.

- is around neutrality; EL< is preferably pH 6.5 to 8.5.

If - is too high, the decolorizing effect will be low, and if it is lower, α-naphthyl acetic acid will crystallize.

The treatment with activated carbon may be a batch treatment with powdered carbon or a continuous treatment with bath treatment. For 'nI products using adsorbent resins, bath treatment is preferred.

Next, − is set to 1.5 to 3.0 to obtain a precursor α containing an inorganic salt.
- Obtain naphthyl vinegar #l.

Furthermore, α-naphthyl e:rRt can be obtained with high purity and high overall yield by washing with water that is sufficient to dissolve the contained salt-free salt and ampering.

Example 1 5! 500 naphthalene in a glass reactor equipped with a stirrer.
g (6,91 mol)t mHcl, ・1600eOj6
Add 5% formalin soy (5.8 mol) and add 307 d of dry HC nogas while stirring at 90'C.
/min for 6 hours. After the reaction, the chloromethyl compound in the lower part was separated and washed with 500 g of 10% charcoal soda solution.

The yield of α-chloromethylnaphthalene was 78.2%. NaCNaC03l in a 5J pressure reactor with a stirrer
59.52 mol), methanol 150,000, cobalt tetracarbonyl anion acetone clear solution 203 co
(contains co(co), -2611), replaces the incoming air with carbon monoxide, then starts heating and stirring to a temperature of 60°C.
After pressurizing to 8 y/cm at C, 758 g of α-chloromethylnaphthalene (N [71%) 7 was added portionwise with a pump within 4 hours. In addition, the reaction was carried out while continuously purging at a rate of 2000/min at the same time as the partial addition, and the mixture was aged for 6 hours after branching.

After the reaction, take out the reaction solution and add 46.51 ml of concentrated sulfuric acid to about 6 oz.
After heating it to 'C', I blew in the desired temperature for 6 hours.

Thereafter, methanol gold was recovered under reduced pressure, water was poured into the tank at 30 ocO, and the tank was sent to the station.

When the reaction solution was analyzed by gas chromatography, α-
493.8 g of naphthyl acetic acid methyl ester (yield: 8
0.8%).

Furthermore, 98.8 g of NaOH (2,47
Add the diluted aqueous solution to a pressure of 150 to 2001 molar
The reaction was carried out for 2 hours at 1 Hg and an internal temperature of 58 to 67°C while distilling methanol off.

By-products were extracted by adding 300'jO4- of toluene to the hydrolysis solution. The - of the aqueous layer was adjusted to 7 using concentrated hydrochloric acid, and powdered activated carbon (t-sg) was added and stirred at room temperature for 8 hours. Filter, remove activated carbon, dilute with hydrochloric acid to give 90.7 g of crystallized α-naphthyl ea.

Further, 1700 g of water was added and the crystals were washed with water and dried to yield 457.1 g of α-naphthyl crystals. The purity of the crystals was determined by rapid chromatography at 99.2%.

The yield from naphthalene was 59.6%.

Comparative Example 1 27,500 g of α-chloromethyl naphtha (itQ degree 71%) obtained in the same manner as in Example 1, Na2C
O3 101g, methanol 955CQ, cobalt tetracarbonyl anion acetone bath fL129cc (
Co (CO) (4-16.6 g of gold scraps) was charged into a 6-layer pressure-resistant reactor equipped with a stirrer, and after 11 hours of aeration with carbon monoxide, 1
The pressure was increased to 6Q "C,5 icg/cm" and the reaction was carried out for 8 hours while simultaneously purging continuously at a rate of 2000/min. Reaction i11['e Analysis by gas chromatography revealed that α-naphthyl acetic acid methyl ester was 213
．． 2g (yield 53%) was produced.

Comparative Example 2 A hydrolyzed PS solution of α-naphthyl acetic acid obtained in the same manner as in Example 1 was crystallized as it was by converting it to -2 using Isoshio cough, resulting in a black tar-like crystallization. Crystal [[t
-56. determined by high performance liquid chromatography.
2% and nine.

〔Effect of the invention〕

According to the method of the present invention, it is possible to produce α-naphthyl e, mtm, in a highly efficient manner, in a fi6 yield, and with still high purity.

Claims (1)

[Scope of Claims] (1) Naphthalene, formalin or formaldehyde, and hydrochloric acid in the presence of mineral acids as an acid catalyst at a temperature of 70°C to
A chloromethylation step in which a solution containing α-chloromethylnaphthalene is obtained by reacting at 100°C, (2) the crude α-chloromethylnaphthalene in the solution containing α-chloromethylnaphthalene is directly treated with carbon monoxide in the presence of a cobalt carbonyl catalyst. , a step of continuously adding crude α-chloromethylnaphthalene or a catalyst to obtain a naphthyl acetate solution in the carbonylation step of reacting a basic substance and an alcohol; (3) cobalt in the naphthyl acetate solution; a catalyst decomposition step in which the carbonyl catalyst is treated with acid and oxygen; (4) a concentration step in which excess alcohol is distilled off from the liquid produced in the catalyst decomposition step; and (5) water or water is added to the concentrated liquid obtained in the concentration step. and an extraction solvent to separate into an organic layer and an aqueous layer,
a step of extracting α-naphthyl acetate from the organic layer and a cobalt compound from the aqueous layer; (6) hydrolyzing the organic layer containing α-naphthyl acetate separated in the extraction step with an acid or alkali without distilling it; Step (7) The hydrolyzate obtained in the hydrolysis step is adjusted to pH 6.
．． The by-products are extracted with an organic solvent that is insoluble in water at a pH of 5 or higher, then the pH is adjusted to around neutrality, decolorized, and the pH is adjusted to 1.5 to 1.5.
3.0, crystallizing α-naphthyl acetic acid, washing inorganic salts in α-naphthyl acetic acid with water, and drying.