The method of obtaining carboxylates of rhodium (ii)

 

(57) Abstract:

Describes how to obtain carboxylates of rhodium (II) by heating the hydrate trichloride rhodium (III) in a mixture of concentrated aliphatic carboxylic acid and an organic solvent in the presence of a salt of the same acid in the atmosphere is chemically inert gas, characterized in that the organic solvent take aprotic polar solvent selected from a range, including dimethylformamide, dimethylacetamide, hexamethylphosphorotriamide, and as salt - carboxylate of diallylamine in the form of a solution in concentrated aliphatic carboxylic acid, the molar ratio of the carboxylate of diallylamine to hydrate trichloride rhodium at least 3:1, the reaction mixture is heated at 85-130oWith in a period of not less than 0.2 h, the mixture was kept in the refrigerator until complete precipitation, the precipitate was separated, washed with acetone, dried in vacuum, the dry residue is treated with excess water or methanol by heating, for example, up to 50-55oWith, separated and dried in vacuum. The technical result - the reduction of the used quantities of low-boiling, flammable and toxic organic solvents, simplifying the process and reducing the of their share capital of platinum group metals, more precisely to a method for the rhodium carboxylates (II), widely used in the preparation of catalysts for industrial organic synthesis.

A known method of producing carboxylate (acetate) rhodium (II) [J. neorg. chemistry, 1966, T. 11, S. 2583-2586] by dissolving 1-2 g H3RhCl6in a mixture of 8-10 ml of concentrated acetic acid, 30-40 ml of water and 10-12 ml of ethanol and heating for several hours. Then the resulting green solution is filtered off from the separated metal and evaporated to small volume, the concentrate is kept in the refrigerator, filtered off the crystals are dark-green, washed with small amount of acetone and dried in vacuum. Output: not more than 40%. Getting carboxylate (acetate) rhodium (II) this process is accompanied by release of metal, and on prolonged heating - education unidentified compounds of rhodium (III).

The main disadvantages of this method are the low yield of the target product, contamination of the final product is a mixture of metal and by-products, as well as the need for a process in a narrow interval of temperature, concentration and duration of heating because of the strong dependence of R, v. 2, R. 960-962] by dissolving suspension of 10.0 g of Rh(OH)3H2About 400 ml of glacial acetic acid by prolonged boiling with obtaining a solution of a deep emerald color. Then the acid is distilled off, first in a water bath, then heated to 120oC. the Residue is repeatedly extracted with boiling acetone to stop the staining of the extract. Hot quickly extract was filtered on a glass filter and concentrate to 1.3 original volume. The hub is kept in the refrigerator. Fallen dark green crystals are separated by filtration, washed with chilled acetone. The obtained adduct [Rh(ASON3)2(CH3)2WITH] 2dried at 110oC. Output [Rh(ASON3)2]2about 50%.

The main disadvantages of this method are its multi-stage, low yield of the target product and the need to use significant quantities of organic chemicals, including flammable and explosive, such as acetone.

The closest in technical essence and the achieved effect is generally accepted in the present method of producing carboxylate (acetate) rhodium (II) [Inorganic Syntheses, 1972, v.13, R. 90-91].

The essence of the method is prototy acetic acid with absolute ethyl alcohol in the presence of sodium acetate to the boil for 1 hour in the atmosphere of a chemically inert gas (argon). The solution is cooled, precipitated precipitate was separated by filtration. The precipitate is dissolved in boiling methanol, the hot solution is filtered, the filtrate concentrated to 2.3 original volume, cooled in the refrigerator, separating the crystalline precipitate of the methanol adduct [Rh(ASON3)2CH3HE]2. The adduct is heated in vacuum at 45oWith 20 hours to quantitative removal of methanol. Yield 76%.

On 1 g of the original three-hydrate of trichloride rhodium take 20 ml of glacial acetic acid, 20 ml of absolute ethanol, 120 ml of methanol.

The main disadvantages of this method are time-consuming and labor that arise because of the need for purification of the target product from the impurities of the metal and sodium chloride by recrystallization of the product. The need for recrystallization of the product entails the consumption of significant quantities of combustible organic, low-boiling and toxic solvents, such as methanol. When enlarged scale synthesis process is complicated by the need for regeneration of large amounts of solvent.

The technical result of the invention is to reduce the quantities of low-boiling, flammable and toxic organic the technical result is achieved by the fact that to receive rhodium carboxylates (II) use the method of heating the hydrate trichloride rhodium (III) in a mixture of concentrated aliphatic carboxylic acid and an organic solvent in the presence of a salt of the same acid in the atmosphere is chemically inert gas, characterized in that the organic solvent take aprotic polar solvent selected from a range, including dimethylformamide, dimethylacetamide, hexamethylphosphorotriamide, and as salt - carboxylate of diallylamine in the form of a solution in concentrated aliphatic carboxylic acid, the molar ratio of the carboxylate of diallylamine to hydrate trichloride rhodium at least 3:1, the reaction mixture is heated at 85-130oC for at least 0.2 hours, the mixture was kept in the refrigerator until complete precipitation, the precipitate was separated, washed with acetone, dried in vacuum, the dry residue is treated with excess water or methanol by heating, for example, up to 50-55oWith, separated and dried in vacuum.

The claimed process is based on studied by the authors of this application reduction reaction of rhodium (III) by its interaction with Carboniferous organic solvents, such as dimethylformamide [J. neorg. hee is 83, S. 52-65]. In the method-prototype function reductant rhodium (III) also performs the organic solvent is ethanol. However, its interaction with the source connection of rhodium (III) is not selective and is accompanied by a partial recovery of rhodium to the free metal.

In the proposed method uses the following ratio of ingredients: per 1 g of tetrahydrate of trichloride rhodium take at least 10 ml of dimethylformamide, at least 10 ml of concentrated aliphatic carboxylic acid.

Significant differences of the proposed method from the prototype method are the following signs: as the organic solvent take aprotic polar solvent selected from a range, including dimethylformamide, dimethylacetamide, hexamethylphosphorotriamide, and as salt - carboxylate of diallylamine in the form of a solution in concentrated aliphatic carboxylic acid, the molar ratio of the carboxylate of diallylamine to hydrate trichloride rhodium at least 3:1, the reaction mixture is heated at 85-130oC for at least 0.2 hours, the mixture was kept in the refrigerator until complete precipitation, the precipitate was separated, washed with acetone, dried in vacuum, the dry residue is treated with excess of water is private to the implementation.

Example 1.

5.0 g RhCl34H2O dissolved in 50 ml of dimethylformamide (hereinafter DMF), the solution is filtered and saturated with argon within 0.3 hours In a stream of argon add 40 ml of glacial acetic acid (hereinafter Asón) and 11 ml 5,65 N. solution of the acetate dimethylammonio (hereinafter DMAA) in glacial acetic acid (the molar ratio of DMAA: the hydrate of trichloride rhodium 3,5:1). In this fall-violet-red precipitate. The reaction mixture is heated at 100oC for 1 h the Precipitate disappears, and the color of the solution turns green. The reaction mixture is cooled at 0oC. the Precipitated crystalline green precipitate is filtered off, washed twice with acetone and 15 ml, dried without heating in vacuum. The resulting product is poured 10 ml of distilled water and heated at 55oWith the disappearance of the absorption maxima at 3200 cm-1and 3150 cm-1in the IR spectrum of samples to be taken. Green crystals are filtered, washed with 3 ml of acetone and dried in vacuum. From the filtrate by adding acetone allocate an additional amount of the substance. The product obtained corresponds to the formula of water adduct [Rh(ASON3)2H2O]2. Output 0,63 g (75%). The increased duration of the heating of reaction, see the.

For RhC4H8O5:

Calculated, %: Rh 43,05; 20,09; N 3,35.

Found, %: Rh 43,40; 19,96; N 3,24.

Identification of the target product is confirmed also by the data of IR spectra. (CO2): 1584, 1452 cm-1, (RhO): 386, 375, 342 cm-1(compare [J. neorg. chemistry, 1979, T. 24, S. 3330-3336]).

Example 2.

Getting [Rh(ASON3)2H2O] 2carried out as described in example 1, but reduce the scale of the experiment (1G Rhl34H2O). Yield 75%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 3.

Getting [Rh(ASON3)2H2O]2carried out as described in example 2, but change the reaction to 1.25 hours product Yield of 75%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 4.

Getting [Rh(ASON3)2H2O] 2carried out as described in example 2, but change the number entering the reaction of acetic acid to 4 ml. Yield of 32%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 5.

Getting [Rh(ASON3)2N

Example 6.

Getting [Rh(ASON3)2H2O] 2carried out as described in example 2, but the reaction temperature change of up to 130oWith the response time to 0.2 h Parallel to the course of reactions of carbonyl rhodium, accelerating at a given temperature. In the IR spectrum of the mother liquor are intense absorption band dicarbonyl complex [Rh(CO)2CL2]-(two lanes in the area 2070-1990 cm-1), the reaction may be followed by selection of the metal. Yield 70%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 7.

Getting [Rh(ASON3)2H2O]2carried out as described in example 6, but change the response time to 0.7 PM See the emergence of a metal that occurs when you restore dicarbonyl complex [Rh(CO)2CL2]-. The product is recrystallized from water. Yield 64%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 8.

Getting [Rh(ASON3)EMA reaction to 1.5 hours Yield 60%. Elemental analysis and IR spectra of the product correspond to the data given in example 1. Further increase in the duration of the reaction does not affect the product yield.

Example 9.

Getting [Rh(ASON3)2H2O] 2carried out as described in example 2, but changing the molar ratio of DMAA: rhodium to 4.0:1. Yield 75%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 10.

Getting [Rh(ASON3)2H2O]2carried out as described in example 2, but changing the molar ratio of DMAA: rhodium to 3.0:1. Yield 54%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 11.

Getting [Rh(ASON3)2H2O]2carried out as described in example 2, but change the concentration of the solution DMAA to 10.0 N. and accordingly change the number of input solution DMAA to 1.3 ml Yield 75%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 12.

Getting [Rh(ASON3)2H2O]2exercise, as opiso solution DMAA to 2.5 ml. Yield 75%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 13.

Getting [Rh(ASON3)2CH3OH]2carried out, as described in the example, but the "raw" product pour 5 ml of methanol and heated at 50oWith the disappearance of the absorption maxima at 3200 cm-1and 3150 cm-1in the IR spectrum of samples to be taken. Green crystals are filtered, washed with 3 ml of acetone and dried in vacuum. The product obtained corresponds to the formula of the methanol adduct [Rh(ASON3)2CH3HE] 2. A yield of 75%. The composition of the obtained product was confirmed by the results of elemental analysis.

For RhC5H10O5:

Calculated, %: Rh 40,67; 23,73; N 3,95.

Found, %: Rh 41,09; 23,41; N 4,12.

The product identification is confirmed also by the data of IR spectra. (CO2): 1580, 1450 cm-1(compare [J. neorg. chemistry, 1979, T. 24, S. 3330-3336]).

Example 14.

Getting [Rh(ASON3)2H2O]2carried out as described in example 2, but replaces DMAA acetate, diethylamine. Yield 73%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.oC for 1 hour. The green solution is cooled at 0oC. the Precipitated crystalline green precipitate is filtered off, washed twice with acetone and 3 ml, dried in vacuum. The resulting product pour 3 ml of distilled water and heated at 55oWith the disappearance of the absorption maxima at 3200 cm-1and 3150 cm-1in the IR spectrum of samples to be taken. Green crystals are filtered, washed with 3 ml of acetone and dried in vacuum. The product obtained corresponds to the formula [Rh(ASON3)2H2O] 2. Yield 0.35 g (43%). Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 16.

Getting [Rh(ASON3)2H2O]2carried out as described in example 15, but replacing the DMA on hexamethylphosphorotriamide (GMPTA). Yield 49%. Elemental analysis and IR spectra of the product correspond to the data given in example 1.

Example 17.

Getting [Rh(EA2H5

For RhC6H12O5:

Calculated, %: Rh 38,53; 26,98; N 4,49.

Found, %: Rh 38,40; 26,66; N 4,24.

The product identification is confirmed also by the data of IR spectra. (CO2): 1582, 1472 cm-1, (RhO): 435, 415 cm-1(compare [J. of General chemistry, 1976, T. 46, S. 1197-1200, J. of General chemistry, 1977, T. 47, S. 2592-2596]).

Example 18 (control prototype).

Rhl34H2Oh (5.0 g) is heated with a trihydrate of sodium acetate (10 g) in a mixture of glacial acetic acid (100 ml) in absolute ethanol (100 ml) to boiling for 1 hour in the atmosphere of a chemically inert gas (nitrogen). The solution is cooled, precipitated precipitate was separated by filtration. The crude product is dissolved in boiling methanol (~600 ml), the hot solution is filtered, the filtrate is concentrated to 400 ml, cooled in the refrigerator overnight, separating the crystalline precipitate of the methanol adduct [Rh(ASON3)2CH3HE]2. The output of 3.05 g (73%).

For Rh5H10O5:

Calculated, %: Rh 40,67; 23,73; N 3,95.

Found, %: Rh 41,00; 23,61; N 4,14.

These examples show that the proposed method of synthesis has advantages in the manufacturing process and reducing the cost of time and labor and not inferior to the prototype method on the yield of the product (examples 1 and 18), and the data of elemental analysis and IR spectra confirm the purity of the product. The use of the acetate dimethylammonio instead of sodium acetate eliminates time-consuming stage of recrystallization of the crude product from methanol and simplifies the process. The data of examples 1-17 are presented in the form of a table.

The optimal amount aprotic solvent and the molar ratios of the reagents are determined by the following factors.

The amount taken in response aprotic solvent is determined by the solubility therein of rhodium chloride. For reducing the volume of solvent (less than 10 ml per 1 g of rhodium chloride) is incomplete dissolution of the original rhodium chloride, resulting in the contamination of the target product. The increase in the polar aprotic solvent reduces the yield of the target product.

The amount introduced into the reaction concentrated aliphatic carboxylic acid is optimal in the interval relations of quantity to the amount of aprotic solvent 1-1,3: 1. When you change this ratio to 0.4:1 (example 4) or up to 1.6:1 (example 5) the yield of the target product is reduced.

The optimal molar ratio of the carboxylate of diallylamine (CDAA) to the rhodium 3-4: 1. If is does not increase the yield of the target product.

Examples of specific performance are evidence that the technical result is achieved. Created a method of obtaining the target product, the yield and purity of the rhodium carboxylate (II) is similar to the prototype method, when used to order smaller quantities of volatile, toxic and flammable organic solvents and with a substantial reduction in time and labor.

The method of obtaining carboxylates of rhodium (II) by heating the hydrate trichloride rhodium (III) in a mixture of concentrated aliphatic carboxylic acid and an organic solvent in the presence of a salt of the same acid in the atmosphere is chemically inert gas, characterized in that the organic solvent take aprotic polar solvent selected from a range, including dimethylformamide, dimethylacetamide, hexamethylphosphorotriamide, and as salt - carboxylate of diallylamine in the form of a solution in concentrated aliphatic carboxylic acid, the molar ratio of the carboxylate of diallylamine to hydrate trichloride rhodium at least 3: 1, the reaction mixture is heated at 85-130oWith in a period of not less than 0.2 h, the mixture was kept in the refrigerator until complete precipitation, asadorian, for example, up to 50-55oWith, separated and dried in vacuum.

 

Same patents:

The invention relates to new chemical substances with the General formula M'nM(H-1GluTrp)mn2Oh, where M' is a cation of an alkali metal, M is a cation d-metal or alkaline-earth metal, GluTrp - anion glutamylation, n is the number of atoms of alkali metal, m is the number of water molecules

The invention relates to a new stable complex compound containing macrocyclic tetradentate ligand having the structure of formula I, where R1and R2have the same or different values are related or unrelated, and each is selected from the group consisting of hydrogen, halogen, methyl, CF3and, if they are connected, cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl, are spatial and confirmation difficult, so that the oxidative degradation of complex metal compound is limited, when the complex is in the presence of an oxidizing environment, Z represents a stable to oxidation atom, which metallocomplexes selected from nitrogen and oxygen, X represents an oxidation resistant functional group selected from O or NRswhere Rsrepresents a methyl, phenyl, hydroxyl, auxillou group, CF3or CH2CF3, R3, R4, R5represent fragments of connecting adjacent Z atoms containing structure described in the claims

The invention relates to a new stable complex compound containing macrocyclic tetradentate ligand having the structure of formula I, where R1and R2have the same or different values are related or unrelated, and each is selected from the group consisting of hydrogen, halogen, methyl, CF3and, if they are connected, cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl, are spatial and confirmation difficult, so that the oxidative degradation of complex metal compound is limited, when the complex is in the presence of an oxidizing environment, Z represents a stable to oxidation atom, which metallocomplexes selected from nitrogen and oxygen, X represents an oxidation resistant functional group selected from O or NRswhere Rsrepresents a methyl, phenyl, hydroxyl, auxillou group, CF3or CH2CF3, R3, R4, R5represent fragments of connecting adjacent Z atoms containing structure described in the claims

- cyclodextrin and method of suppressing tumor growth" target="_blank">

The invention relates to organic chemistry, and medicine, and it applies to substances used in combination with ascorbic acid for the treatment of malignant neoplasms (binary catalytic "dark" therapy of malignant tumors) and method of suppressing tumor growth
The invention relates to methods for dilaceration chelates of iron and can be used, for example, in agriculture as a protective means and in veterinary medicine

The invention relates to the synthesis of bridge mu-oxo-perchloroethene (III) of tetraalkylammonium General formula [R4N]3[Fe2Cl7O], where R is lower alkyl, and to a method for bridging mu-oxo-perchloroethene (III) of tetraalkylammonium possessing properties improper ferroelectric
The invention relates to organic chemistry and relates to a method of obtaining succinate d-elements - of biologically active substances complex action

The invention relates to new salts of (4-hydroxy-3,5-di-tert-butylphenyl)-propionic acid of General formula 1, where R is C(CH3)3; Me represents a metal selected from the group of Zn, BA, and CA; n is the valence of the metal and is equal to 2, which is produced by interaction of the methyl ester (4-hydroxy-3,5-di-tert-butylphenyl)-propionic acid with oxide of a metal selected from Zn, BA, CA, in the aquatic environment and/or environment C1-C4aliphatic alcohol at a temperature of 85-130oC and a pressure of 1-4 atmosphere at a molar ratio of the ether : the oxide of the metal equal to 1-0,50 : 0,520

The invention relates to petrochemical synthesis, namely the method of production of metal-containing stabilizer is polyvinyl chloride, and may be used in the production of PVC films, artificial leather, cable compound, etc

The invention relates to a method for producing calcium stearate, where the process is carried out by interaction of stearic acid and calcium hydroxide in the presence of a solvent, acetone or a water-acetone mixture (containing acetone at least 25 wt

The invention relates to the production of salts of acetic acid

The invention relates to ORGANOMETALLIC chemistry, namely to new connections, particularly to salts (4-hydroxy-3,5-di-tert-butylphenyl)-propionic acid of General formula

< / BR>
where R = C(CH3)3, Me is a metal selected from the group of Zn, Ba, Ca, Cd, Al, Sn, Mg, Cr+3, Mn+2, n is the valence of the metal, n = 2 to 4, which can find use as a stabilizer for polymers and additives to oils
The invention relates to the production of paint and varnish materials, namely, synthetic drying oils on the basis of naphthenic acids

The invention relates to the field of synthesis of organic metal salts, such as 2-ethylhexanoate metals, which are used in the production of polymeric materials, stabilizers and modifiers, allowing you to modify the rheological properties of polymer materials, and also as additives to paints, varnishes, lubricants and raw materials for thin film deposition of complex oxides
The invention relates to a method for allocation of fluorinated carboxylic acids, allowing you to get them with a high degree of purity

FIELD: organic chemistry, chemical technology, agriculture.

SUBSTANCE: invention relates to a method for preparing the preparation comprising triterpenic acid water-soluble salts and additionally added protein-containing product and vegetable raw, the source of triterpenic acids taken in the following ratio of components, wt.-%: protein-containing product, 10-17; triterpenic acid sodium salts, 4-5, and vegetable raw, the balance. Method involves mixing triterpenic acid-containing vegetable raw with the protein-containing product taken in the ratio = (9-11):(1-2), mechanical-chemical treatment of this mixture in activator device, mixing of prepared semi-finished product with sodium carbonate or sodium hydrocarbonate taken in the ratio = (92-97):(3.5-8.3) and repeated treatment in the activator device. Method involves applying flow-type ball vibration-centrifugal or ellipse-centrifugal mills as the activator device that provide the acceleration of milling bodies up to 170-250 m/c2 and time for treatment for 1.5-3 min. Invention provides simplifying the process and the complex processing waste in lumber industry.

EFFECT: improved preparing method.

6 cl, 1 tbl, 6 ex

Up!