HU187412B - Process for preparing cu-8-hydroxy-quinolate - Google Patents

Abstract

The present invention relates to the preparation of copper-8-hydroxyquinoline. In the process, o-nitrophenol and acrolein are added to the solution containing o-aminophenol acetic acid and hydrochloric acid and / or hydrogen bromide with stirring at 80 110 ° C, and the reaction mixture is adjusted, if necessary, by pH adjustment and containing divalent copper ions. an inorganic salt or a copper amine complex with an aqueous solution. Finally, the product is recovered by filtration. The product thus obtained has a purity of at least 90-95% and can thus be directly converted to a plant protection product. -1-

Description

The present invention relates to a process for the preparation of copper 8-hydroxyquinolate.

It is known that 8-hydroxyquinoline forms a strong complex with divalent copper salts, which due to its fungicidal action can be used as a plant protection product. To prepare pure 8-hydroxyquinoline, an aqueous solution is reacted with divalent copper salts and an equivalent base. In recent years, some processes have been known for preparing the 8-hydroxyquinoline copper complex by dissolving the copper sulfate in the reaction mixture itself and recovering the product. Thus, the starting material is quinoline-8-sulfonic acid (Japanese Patent Laid-Open No. 69-30,508, Japanese Kokai Patent Nos. 73-54,078), which is subjected to alkaline hydrolysis and then treated with 80 molar equivalents of copper sulfate in an aqueous solution of the Copper-8-hydroxyquinolate is obtained in 95% yield. These methods, while yielding good yields of the target product, are nonetheless disadvantageous because they are difficult to access and expensive starting materials, and the alkaline hydrolysis requires very high temperatures of 250-280 ° C.

More preferred Manske et al., Can. J. Sl. 27 (9), 359 (1949)] and, as an improvement, see U.S. Patent No. 525,675. A process described in U.S. Patent No. 5,198, wherein a mixture of ortho-aminophenol, orthonitrophenol, sulfuric acid and glycerol is reacted at 130-140 ° C and copper sulfate is added to the reaction mixture to form copper-8-hydroxyquinolate. The yield of the product thus obtained is inadequate (60-70%) and purity is only 90-95%.

It is an object of the present invention to provide a process which simply produces high-quality copper-8-hydroxyquinolate in good yield.

In our experiments, it has been found that when the hydrochloric acid solution of o-aminophenol is reacted with o-nitrophenol and acrolein, the resulting aqueous hydrochloric acid reaction mixture is surprisingly capable of directly producing copper-8-hydroxyquinolate.

The present invention relates to a process for preparing copper-8-hydroxyquinolate by adding acrolein and aminophenol to an aqueous solution of ortho-aminophenol containing acetic acid and hydrochloric acid and / or hydrobromic acid at 80-110 ° C and adjusting the pH, if desired. after mixing with a solution containing divalent copper ions.

The molar ratio of o-nitrophenol to o-aminophenol is preferably close to 1: 2. And 3-4 moles of acrolein per mole of o-nitrophenol are added to the reaction mixture. The dosing time may vary from a few minutes to 5-10 hours.

After the addition of the acrolein, the reaction mixture is suitably stirred for 0.5 to 1 hour at the reaction temperature of 8 (M10). The amount of copper sulfate is 2.5 to 3.5 moles per mole of nitrophenol. It can be added to the reaction mixture immediately Alternatively, before the addition of copper sulfate, the pH of the reaction mixture is increased with a base, preferably sodium or potassium hydroxide. If the pH is raised to 3, most of the impurity can be removed by filtration or extraction, After neutralization of the solution to pH 6, the precipitated solid product is dissolved in an aqueous mineral acid, and the by-products can be removed by activated charcoal clarification, after addition of a base, preferably sodium or sodium sulfate. with potassium hydroxide, the product was isolated.

Upon completion of the addition of acrolein, the pH of the reaction mixture can be raised to above 10 and the resulting solution is treated with copper sulfate, preferably in the form of an aqueous solution. Copper-8-hydroxyquinolate is precipitated immediately and can be isolated by filtration.

In a preferred embodiment of the process according to the invention, after the addition of acrolein, the pH of the reaction mixture is adjusted to 3-4 and the impurities are removed by filtration. The pH is then adjusted to 6-8, acidified again with concentrated or dilute sulfuric acid to 2-4 and the solution clarified. The clarified solution was added to an aqueous solution of copper tetramine hydroxide, and the precipitated copper 8-hydroxyquinolate was collected by filtration at pH 8-10.

The pH adjustments may be made at room temperature or below, or alternatively, the heat released during neutralization may be worked at temperatures between 50 and 100 ° C. This saves time and cooling energy.

The process of the present invention has the advantage of providing copper-8-hydroxy quinolate of 90-95% purity with readily available and inexpensive starting materials in the usual temperature range of 65-80%. The product thus obtained can be formulated directly into the appropriate pesticide.

Example 1

To a solution of 1.32 mol of o-aminophenol, 1.32 mol of acetic acid and 4 mol of 36% aqueous hydrochloric acid, a solution of 0.68 mol of o-nitrophenol in 2.4 mol of acrolein was added dropwise with stirring at 105 ° C for 2 hours. After stirring for another hour at 104-110 ° C, the solution was cooled and the solution was adjusted to pH 3 with 40% sodium hydroxide solution and adjusted to 1500 ml with water.

The above 150 mL was diluted to 600 mL with water and then adjusted to pH 3.5 with sodium hydroxide. The solution was filtered, the mother liquor was first neutralized with an alkali, and then 0.2 mol of solid sodium hydroxide was added. Copper sulfate (0.1 mol) in water (50 mL) was then added. The product was filtered, washed with water and dried at 110 ° C. Copper-8-hydroxyquinolate (28.3 g, 80% yield) was obtained with a purity greater than 90% based on the copper content.

Alternatively, to a solution of the above solution in 150 mL of 0.1 M copper sulfate in 50 mL of an aqueous solution, the pH is adjusted to 6. The product was filtered and washed with 28.4 g, corresponding to an 80% yield. The purity of the final product is 98%.

A reaction was performed in which the pH of the stock solution (150 ml) was adjusted to 4 without dilution, and after filtration, the first procedure was followed. 25 g of product of greater than 98% purity are obtained. This corresponds to a yield of 65%.

187,412

Example 2

A solution of 1500 ml was prepared as described in Example 1, and a quarter of this was treated with 40% sodium hydroxide at 10-15 ° C until the pH was 6. 150 ml of 25% sulfuric acid were added and refluxed for 1 hour. 42.8 g of CuSO ₄ .5H ₂ O were added and the pH was adjusted to 6 with 40% sodium hydroxide solution. The precipitated product was filtered off, washed with water and dried. 58.3 g of product were obtained, corresponding to a 66% yield of o-nitrophenol.

Example 3

All were carried out as in Example 1, but only 1000 ml of aqueous stock solution was prepared from the resulting hydrochloric acid reaction mixture.

To 100 ml stock solution (0.2 mol) was added 50 ml water and 100 g ice and neutralized to pH 6 with 40 ml 40% sodium hydroxide. The filtered material was mixed with 150 mL of water and then mixed with 25 mL of 20% sulfuric acid. After suspending for half an hour at 90-95 ° C, 0.1 M copper sulfate was added after clarification with activated carbon and the pH was adjusted to 4.5 with 40% sodium hydroxide. The filtered and dried product was 26.7 g (75.5%).

Next, 0.1 mol of copper sulfate in 150 ml of aqueous solution was added to 150 ml of stock solution and the precipitate was filtered off (3.5 g). After neutralization with 40% alkali, the precipitated product was filtered off and the mother liquor was further neutralized, depending on pH, to give the following product:

pH = 1 14.2 g ; pH 5 n 0g pH = 2 8.4 g pH = 4 0.8 g altogether: 34.4 g (97%)

Finally, 0.055 moles of copper sulfate in 80 ml of aqueous solution were added to 50 ml of stock solution and the pH was adjusted to 4.5 with 40% alkaline solution. The filtered product was washed with water and then suspended in a mixture of 30 ml of 30% sulfuric acid and 190 ml of water, stirred at 90-95 ° C for 1 hour, clarified with 3 g of activated carbon and filtered. The mother liquor was neutralized to pH 5 with 40% alkali and the product was filtered off and washed with water. 12.8 g of product were obtained, which was more than 99% pure.

Example 4

To a 105 ° C mixture of 0.2 molar o-aminophenol, 0.66 mol hydrobromic acid, 1 ml glacial acetic acid and 57 ml water was added 0.1 mol o-nitrophenol and 0.36 mol acrolein over 2 hours. After stirring for 1 hour at this temperature, 76 ml of 40% sodium hydroxide was added followed by 50 ml of 30% sulfuric acid. The temperature was maintained at 90-95 C for 1 hour. After clarification with activated carbon, the mixture was mixed with 0.15 moles of copper sulfate in 100 mL of water and the product was precipitated with 40 mL of 40% sodium hydroxide. Filtration, washing with water and drying gave 44 g (83%) of product with a purity of 101% based on copper.

Example 5 A mixture of 0.5 molar orthonitrophenol and 1.65 mol acrolein was added dropwise over 2 hours to a 105-110 ° C mixture of mole ortho-aminophenol hydrochloride, 2 moles of hydrochloric acid and 1 mole of acetic acid. It was stirred for 1 hour and then cooled. 620 g of solution were obtained.

31 g of this solution were diluted with water (30 ml), dichloroethane (25 ml) was added and neutralized to pH 7 with 2N sodium hydroxide. After extraction with dichloroethane (50 ml), the aqueous phase was re-extracted. The organic phases were evaporated, dissolved in a mixture of 5 g cc hydrochloric acid and 30 ml water and added to a mixture of 6.25 g (0.025 mol) of crystalline aqueous copper sulfate and 10.2 g of ammonium hydroxide. Precipitated copper 8-hydroxyquinolate was filtered, washed with warm water and dried. Yield: 7.7 g (58%), 96% based on 8-oxoquinoline.

Example 6

From the solution obtained in Example 5, 46.5 g was diluted with 100 ml of water and neutralized with 18 ml of 40% alkaline to pH 7. The ρΗ value was then adjusted to 2-3 with 21 ml of 30% sulfuric acid, held at 90-95 ° C for 1 hour, and then clarified with 2.5 g of activated carbon. The filtrate was added to a mixture of 9.8 g of copper sulfate and 15.7 ml of ammonia solution. The precipitated copper 8-hydroxyquinolate was filtered, washed with water and dried. Yield: 12.1 g (61.8%), 92.4% based on 8-oxoquinoline.

Example 7

All were carried out according to Example 6, but nitrophenol was removed from the solution by atmospheric distillation before adjusting to pH 7. 12.3 g (61%) of product are obtained, which is 91% based on the oxide content.

Example 8

62 g of the solution obtained in Example 5 were neutralized to pH 7 with 40% sodium hydroxide solution and then adjusted to pH 3-4 with 30% sulfuric acid. The solution was clarified warm with activated carbon. To the clarified filtrate was added 28 ml of 30% sulfuric acid and 0.06 mol of copper sulfate. The resulting solution was poured into a 20% alkaline solution, filtered at pH 5, washed with water and dried. 16.5 g of copper-8-hydroxyquinolate were obtained (62.5% yield), based on oxime content 94.5%.

187,412

Example 9 The solution obtained in Example 5 (g) was neutralized to pH 7 with 40% sodium hydroxide solution and extracted with dichloroethane (2 x 25 ml) (the emulsion was filtered off after the first extraction).

The dichloroethane phases were extracted with a mixture of 28 ml of 30% sulfuric acid and 100 ml of water, the aqueous phase was adjusted to pH 4 with alkali, and the residue was cooled with carbon.

The clarified solution was poured into a solution of copper tetramine hydroxide (0.06 mol) in water (50 ml). The precipitated product was filtered off, washed with water and dried. 23 g (87%) of product were obtained which was 90% pure by oxime content.

Example 10 g The solution obtained in Example 5 was treated with 24 ml of 40% alkaline solution followed by 28 ml of 30% sulfuric acid solution, diluted with 65 ml of water and 25 ml of aqueous nitrophenol was distilled off at atmospheric pressure. 25 ml of water and 1.5 g of perlite were added to the residue and filtered. To the filtrate was added 15 g of an aqueous solution of copper sulfate in 30 ml and acidified with 25 ml of 30% sulfuric acid. 30 ml of a 40% alkaline solution was diluted twice with water and the acidic solution was added. The precipitated solution was adjusted to pH 4-4.5, filtered and the product washed with water and finally dried. 17.9 g (67.8%) of copper-8-hydroxyquinolate were obtained, which was 87% based on the copper content obtained.

Example 11 A solution of Example 5 (g) was diluted with 200 mL of water and 0.9 g of perlite was added, then neutralized to pH 3 4 with 16.1 g of 40% alkali and filtered. 28 ml of 30% sulfuric acid were added to the filtrate, and 10 ml of water were distilled off to remove the nitrophenol. To the residue was added copper sulfate (13.1 g) and a solution of 40 g of a 40% alkaline solution in 50 ml of water. The pH was adjusted to 6 with 10 mL of sulfuric acid, and the precipitate was filtered off and washed with water. Copper-8-hydroxyquinolate (16.1 g, 61% yield) was 87.5% based on oxime content.

Example 12 A solution of 210 g of orthonitrophenol and 330 ml of acrolein was added over 2 hours to a mixture of 600 g of ortho-aminophenol hydrochloride, 600 g of cc hydrochloric acid, 180 g of glacial acetic acid. After 1 hour, the solution was stripped of nitro-phenol by steam distillation.

Nitrophenol (16.7 g) was recovered. The residue was diluted with water to 3 kg.

To this, 10 g of perlite was added to 1 kg and 150 ml of 40% alkaline was added dropwise. The resulting tar was filtered off and washed with a little water. To the filtrate was added 10 g of perlite, 120 ml of 40% alkaline, followed by 1: 1 sulfuric acid until pH 2 was reached. It was clarified hot with 10 g of charcoal and filtered after cooling. The residue was added to a mixture of 131 g of copper sulfate, 216 g of 25% ammonia and 270 g of water with stirring at 70 ° C. The material was filtered hot, washed with hot water and dried. Yield: 193 g (72.5%).

Example 13

All were prepared in the same manner as in Example 12, but using an equivalent amount of 25% ammonia instead of 40% sodium hydroxide solution. The product was filtered at pH 8 then washed and finally dried. Yield: 93.7% (60%).

Example 14 g The solution obtained in Example 5 was treated with 24 ml of a 40% alkaline solution followed by 28 ml of a 30% solution of sulfuric acid, diluted with 65 ml of water and 25 ml of aqueous nitrophenol was distilled off at atmospheric pressure. 25 ml of water and 1.5 g of perlite were added to the residue and filtered. To the filtrate was added 12 g of an aqueous solution of copper chloride and acidified with 25 ml of 30% sulfuric acid. 30 ml of a 40% alkaline solution was diluted twice with water and the acidic solution was added. The precipitated solution was adjusted to pH 4-4.5, filtered and the product washed with water and finally dried. 17.9 g (67.8%) of copper 8-hydroxyquinolate were obtained, which was 87% based on the copper content obtained.

Claims (4)

Patent claims CLAIMS 1. A process for the preparation of copper 8-hydroxyquinolate comprising adding 1 mol of o-nitrophenol and 3-4 mol of acrolein to a solution of 2 mol of o-aminophenol acetic acid and hydrochloric acid and / or hydrobromic acid. at 80-110 ° C and thereafter, if desired, the pH is adjusted to between 2 and 6 or 8 to 13 and the impurities are removed by clarification or steam distillation, and the reaction mixture is 1.2-1.8 based on the starting materials. aqueous solution of an inorganic salt or copper amine complex containing a mole of divalent copper ion, the pH is adjusted to 2-6 and the product is recovered in a known manner. (Priority: May 4, 1983). 187 412 2. A process according to claim 1 wherein the divalent copper compound is copper tetramine hydroxide. (Priority: May 4, 1983) 3. A process for the preparation of copper-8-hydroxyquinolate comprising adding a solution of o-nitrophenol acrolein in an aqueous solution containing 80% to 110 ° C of a solution of azo-o-aminophenoleacetic acid and hydrochloric acid and / or hydrobromic acid. and optionally the pH of the reaction mixture is 2 to 6 or 8-13, if necessary, the impurities are filtered off, followed by 1.2-1.8 moles of copper based on a 1: 2: 3-4 molar mixture of o-nitrophenol, o-aminophenol and acrolein sulfate is added to the reaction mixture, optionally clarified, the pH is adjusted to 2-6, and the product is recovered in a known manner. (Priority: September 20, 1982)