RU2584952C1 - Hydride-carbonyl polyphosphite complex of rhodium with mixed organophosphorus ligands for catalysis of hydroformylation of olefins - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to a hydride-carbonyl polyphosphite complex of rhodium with mixed organophosphorus ligands. Complex has general formula HRh(CO)(A)(B), where A is a polyphosphite ligand of general formula:

wherein k + m = 2, where it is possible for k = 0 or m = 0; X is a hydrocarbon radical comprising 1 to 50 carbon atoms; Z are identical or different in fragments of m hydrocarbon radicals having 2 to 30 carbon atoms; Y are identical or different hydrocarbon radicals having 1 to 30 carbon atoms; B is an organophosphorus ligand selected from organophosphine of general formula (R1)(R2)(R3)P or organophosphinite of general formula (R1)(R2)P(OR3), wherein R1, R2, R3 are hydrocarbon radicals having 6 to 30 carbon atoms. A method of producing the complex is also disclosed.

EFFECT: obtained complex is used as a catalyst in hydroformylation of olefins and enables to improve regioselectivity of hydroformylation on linear aldehydes while maintaining high catalyst activity and stability.

2 cl, 1 tbl, 20 ex

Description

The invention relates to basic organic, fine organic and petrochemical synthesis and relates to a catalyst for hydroformylation of olefins into the corresponding aldehydes.

The production of aldehydes by hydroformylation of olefins in the presence of synthesis gas (a mixture of carbon monoxide and hydrogen) is a large-capacity process in the chemical industry. The reaction, as a rule, leads to a mixture of linear (normal - “n” aldehydes) and branched (“i” - iso) aldehydes, and in most cases linear products are preferred for practical purposes, therefore regioselectivity for n-aldehydes S _n = n / (n + i) is the most important indicator of the process.

As hydroformylation catalysts, soluble rhodium complexes with monodentate tertiary phosphine ligands, in particular triphenylphosphine (Ph ₃ P), are widely used in industry today. Unlike previously used cobalt catalysts, such complexes allow the process to be carried out under relatively mild conditions with high chemical selectivity for aldehydes. However, to achieve high regioselectivity (S _n > 90%), high concentrations of triphenylphosphine in the reaction mixture are required. According to the patents US 4287370, US 4593127, US 5053551, the weight content of the indicated ligand should be more than 10% (for example, 30% by weight in US 5367106) and, moreover, the contact gas should be significantly enriched with hydrogen, whereas synthesis stoichiometry requires synthesis gas composition WITH: H ₂ 1: 1. The need for a large amount of ligand and the need for special measures to maintain the desired contact gas composition substantially affect the cost of the process.

The regioselectivity, activity and stability of the catalyst are determined by the nature of the organophosphorus ligands. A known olefin hydroformylation catalyst is a precursor composition consisting of a rhodium compound and a polyphosphite ligand dissolved in a suitable organic solvent (US 4,668,651, US 4,769,498, US 5,910,600, US 6,610,891). Moreover, regioselectivity Sn> 90% is achieved even at 0.5-3 weight. % ligand and the ratio of CO: H ₂ in the contact gas of about 1: 1. It is believed that in this case the true catalysts of the process are rhodium hydride carbonyl complexes with polyphosphite ligands A of the HRh (CO) ₂ (A) type, which are formed under hydroformylation from the precursor composition (Organometallics 1996, V. 15, No. 2, P. 835- 847).

The catalysts described in the listed patents are precursor compositions consisting of a rhodium compound (usually rhodium dicarbonyl acetylacetonate) and a phosphoroganic ligand of only one nature. The indisputable advantage of rhodium-polyphosphite catalysts in comparison with rhodium-triphenylphosphine catalysts is significantly lower concentrations of the modifying ligand: the ligand / Rh molar ratio can be reduced to 4, which under typical conditions corresponds to a mass fraction of about 0.5% in the reaction mixture. However, polyphosphites are orders of magnitude more expensive than triphenylphosphine; therefore, a further reduction in the consumption of ligands is practically an important task. It is noteworthy that complexes that include 1 mol of polyphosphite per 1 rhodium atom are catalytically active, while catalytic systems must provide at least 3 mol of polyphosphite in a free state to ensure stable operation and high regioselectivity. Moreover, free phosphites, as well as coordinated ones, degrade in the reaction medium under the action of aldehydes, by-products, and impurities of oxidizing agents in the feed. This causes costs associated not only with the increased consumption of fresh polyphosphite to compensate for the destruction of a larger amount of ligand, but also with measures to divert the destruction products themselves, which, being strong acids, can catalyze the decomposition of ligands.

RU 2352552 describes a stable complex HRh (CO) (A) (Ph ₃ P) ₂ , the use of which in the hydroformylation of olefins, unlike complexes of the HRh (CO) ₂ (A) type, to achieve high regioselectivity S _n does not require the use of an additional amount free polyphosphite A. However, a significant drawback is the decrease in catalyst activity by 2-2.5 times. An analysis of the possible causes of the decrease in activity showed that the presence of two triphenylphosphine ligands in the catalyst, which possess sufficiently strong σ-donor properties and low π-acceptorness, can inhibit the conversion of catalytic cycle intermediates. In this case, a decrease in the number of phosphine ligands in the composition of the catalytic complex, as well as their replacement with less donor and more π-acceptor phosphinites, should lead to an increase in the activity of the catalyst.

The objective of the present invention is to provide an effective hydroformylation catalyst, providing high processability with maximum selectivity for the most popular linear aldehydes and low consumption of expensive components.

The technical result from the use of the inventive catalyst is to increase the regioselectivity of hydroformylation according to linear aldehydes while maintaining high activity and increasing the stability of the catalyst itself, which allows to reduce the consumption of its expensive polyphosphite component, reduce the requirements for cleaning raw materials and simplify technological procedures.

The technical result is achieved in that the hydroformylation catalyst is a rhodium hydride-carbonyl complex of the general formula HRh (CO) (A) (B) with mixed organophosphorus ligands A and B, where A is a polyphosphite ligand of the general formula:

in which k + m≥2, and possibly k = 0 or m = 0; X is a hydrocarbon radical comprising from 1 to 50 carbon carbon atoms; Z — identical or different hydrocarbon radicals in fragments m, comprising from 2 to 30 carbon atoms; Y are the same or different hydrocarbon radicals comprising from 1 to 30 carbon atoms; B is an organophosphorus monodentate ligand selected from organophosphine of the general formula (R1) (R2) (R3) P or organophosphinite of the general formula (R1) (R2) P (OR3), where R1, R2, R3 are hydrocarbon radicals comprising from 6 to 30 carbon atoms.

The fundamental difference between the inventive catalyst HRh (CO) (A) (B) from conventional catalytic complexes with only one polyphosphite ligand A of type HRh (CO) ₂ (A) consists in replacing one CO ligand with a larger and less π-acceptor phosphine or phosphinite (B), which also have pronounced σ-donor properties. As it turned out, this leads both to an increase in the regioselectivity of hydroformylation according to the desired linear aldehydes, and to an increase in the stability of the catalyst, which reduces the consumption of expensive phosphite A and the requirements for the content of impurities in the feed.

Due to the presence of a phosphine or phosphinite ligand B in the coordination sphere of rhodium during dissociative interaction of HRh (CO) (A) (B) with an olefin, along with the π complex HRh (CO) (A) (olefin), the π complex HRh (A) is also formed (B) (olefin), the subsequent transformations of which due to the steric and electronic effects of ligand B (large volume and lower π acceptor compared to the CO ligand) give a higher proportion of linear aldehydes than the conversion of the NRL (CO) complex (A) (olefin). In contrast, the HRh (CO) ₂ (A) catalyst is capable of forming only the π-complex HRh (CO) (A) (olefin), in which the implementation of the catalytic cycle, the introduction of olefin into the H-Rh bond leads to a less high proportion of linear product. Thus, in the case of the HRh (CO) (A) (B) catalyst, the total regioselectivity of the process increases as a result of the contribution of the reaction routes involving the π complex HRh (A) (B) (olefin). The differences in the mechanism of action of the catalysts of both types are explained in the diagram.

In addition, when using both types of catalysts, we found that the individual polyphosphite complex HRh (CO) ₂ (A) shows satisfactory regioselectivity (more than 90% linear aldehyde) only in the presence of an additional amount of free polyphosphite ligand A, whereas in the case of the claimed HRh (CO) (A) (B) catalyst, such an excessive consumption of polyphosphite is not required. Since the regioselective effect is due to the chelate coordination of ligand A with the rhodium atom, the need to use an excess of polyphosphite is most likely caused either by the dissociation of polyphosphite A from HRh (CO) ₂ (A) with the formation of non-regioselective dimeric complexes (reaction 1), or by partial oxidation of one phosphite to the feedstock ligand A groups to phosphate (reaction 2). As a result of reaction (2), the multidentate ligand A turns into a monodentate ligand, whose complexes are also non-regioselective.

In this case, the role of polyphosphite excess is reduced to a shift in equilibrium (1) towards highly selective complexes with chelate coordination of ligand A or to make up for the loss of this ligand in destruction reactions (2). In the case of the claimed complex HRh (CO) (A) (B), reactions (1) and (2) do not proceed or are largely suppressed, therefore, there is no need to stabilize the catalyst with an additional amount of polyphosphite, which reduces its consumption.

We found that the HRh (CO) (A) (B) complexes are several times more resistant to oxygen than the HRh (CO) ₂ (A) complexes, whose contact with air quickly leads to the oxidation of coordinated polyphosphites to the corresponding free phosphates . This effect makes it possible not only to reduce the consumption of an expensive catalyst to compensate for its degradation and reduce the requirements for the quality of raw material purification, but also to simplify technological procedures. This especially applies to the stage of evaporative separation of the product from the catalyst, which is usually carried out at atmospheric pressure or under vacuum. In this case, due to the absence of a stabilizing pressure of the synthesis gas, the catalyst is most susceptible to both spontaneous destruction and destruction under the influence of oxidizing agents. Therefore, it is necessary to take special techniques to reduce the residence time of the catalyst at this stage (RU 2270829), which increases the cost of the process. The use of HRh (CO) (A) (B) complexes instead of HRh (CO) ₂ (A) eliminates this drawback. The high sensitivity of HRh (CO) ₂ (A) to oxygen is probably due to the presence of two strong π-acceptor CO ligands, which favors the dissociation of one of them, and the released coordination vacancy is occupied by oxygen, which causes the oxidation of phosphite A:

In the HRh (CO) (A) (B) complexes, the π-acceptor carbonyl ligand is “compensated” by the σ-donor ligand B, therefore, the dissociation of ligands with the formation of coordinatively unsaturated particles is difficult and reactions of type (3) proceed at a significantly lower rate.

In carrying out the invention, HRh (CO) (A) (B) catalytic complexes are obtained by treating with synthesis gas a solution of a compound of rhodium, polyphosphite A and organophosphine or organophosphinite B with a molar ratio of Rh: A: B equal to 1: 1: 1 in a hydrocarbon solvent medium at a partial pressure of synthesis gas of at least 0.1 MPa and temperatures of 30-120 ° C. Then the solvent is evaporated under vacuum and the product is isolated in the solid state. The resulting material is used as a hydroformylation catalyst.

The HRh (CO) (A) (B) complex obtained by this method can be used as a catalyst in the form of a solution without its isolation in the solid state. This option can be implemented directly in the reaction medium hydroformylation.

As the rhodium compound, soluble complexes and salts not containing anions of mineral acids can be used. Affordable and stable acetylacetonates and carboxylic acid salts are best suited. The lower temperature limit and the minimum synthesis gas pressure in the preparation of the catalyst are limited by practically acceptable reaction completion times. At temperatures above 120 ° C, thermal destruction of polyphosphite is possible. The solvent should provide good solubility of the rhodium precursor and ligands. Low-polar aprotic solvents, in particular aromatic hydrocarbons, are best suited.

The implementation of the present invention is illustrated by the following examples.

Example 1

According to the invention, this example demonstrates the formation of complexes of the type HRh (CO) (A) (B), where A corresponds to polyphosphite A1 and B to triphenylphosphine (Ph ₃ P). Rhodium dicarbonyl acetylacetonate (19.31 mg, 0.075 mmol), polyphosphite A1 (62.71 mg, 0.075 mmol), triphenylphosphine (19.68 mg, 0.075 mmol) and 2 ml of C ₆ D ₆ (previously purified by distillation over sodium) using a technique that excludes contact with air , placed in a miniature glass autoclave and the solution is kept under stirring under a synthesis gas pressure of 1 MPa and a temperature of 45 ° C for 3 hours. After cooling the autoclave, the synthesis gas is replaced by argon and a sample is introduced into the ampoule for NMR spectra recording, pre-filled with purified argon. In the ³¹ P NMR spectra, complex multiplet signals are observed due to the mutual splitting of the three phosphorus nuclei in the HRh (CO) (A1) (Ph ₃ P) complex, in which the P1 and P2 nuclei of the ligand A1, in contrast to the complex HRh (CO) ₂ (A1 ) in Example 1C are magnetically nonequivalent. Detailed interpretation of the ³¹ P { ¹ H} NMR spectrum gives the following correlation, δp (ppm): 178.6 (m, 1P, ¹ J _Rh-P1 = 252 Hz, ² J _P2-P1 = 279 Hz, ² J _Ph3P-P1 = 168 Hz, P1), 175.9 (m, 1P, ¹ J _Rh-P2 = 246 Hz, ² J _P1-P2 = 279 Hz, ² J _Ph3P-P2 = 146.5 Hz, P2), 35.9 (m, 1P, ¹ J _Rh-PPh3 = 140 Hz, ² J _P1-PPh3 = 168 Hz, ² J _P2-PPh3 = 146.5 Hz, Ph ₃ P). The ¹ H NMR spectrum confirms the structure of HRh (CO) (A1) (Ph ₃ P), δ _H (ppm): - 10.44 (m, 1H, ¹ J _Rh-H = 3 Hz, ² J _P1-H = 0 Hz, ² J _P2-H = 21 Hz, ² J _Ph3P-H = 7 Hz, H-Rh), 1.12 (s, 9H, tC ₄ H ₉ ), 1.23 (s, 9H, tC ₄ H ₉ ), 1.88 (s , 9H, tC ₄ H ₉ ), 2.04 (s, 9H, tC ₄ H ₉ ), 6.53-7.85 (m, 35H, Ar). In this case, the resonance signals of free polyphosphite A1 (δp 145.4 ppm) and triphenylphosphine (δp - 8 ppm) are not observed, and the integrated signal intensity of the HRh (CO) ₂ (A1) complex in the region of _{P P} 172.7 ppm is less than 1% of the total number of nuclei ³¹ P, which indicates almost complete binding of the ligands to the complex HRh (CO) (A1) (Ph ₃ P). The contents of the autoclave and the ampoule are combined, evaporated in vacuo with gentle heating in a water bath and the remaining material is dissolved in 1.5 ml of mesitylene. IR spectrum (cm ^-1 ): 2038 s, 1953 sl. Absorption bands of the starting rhodium dicarbonyl acetylacetonate (2081 and 2010 cm ^-1 ) and the HRh (CO) ₂ (A1) complex (2077, 2031, 2019 and 1983 cm ^-1 ) are absent. The synthesis of HRh (CO) (A1) (Ph ₃ P) is repeated, replacing 2 ml of deuterobenzene with 1.5 ml of freshly distilled mesitylene over sodium, the synthesis gas being bubbled through the solution for 4 hours at atmospheric pressure and heating to 55-60 ° C. A completely identical IR spectrum is obtained.

Comparative Example 1C

This example demonstrates the synthesis of complexes of the HRh (CO) ₂ (A) type with the individual polyphosphite ligand A1.

Rhodium dicarbonyl acetylacetonate (19.31 mg, 0.075 mmol), polyphosphite A1 (62.71 mg, 0.075 mmol) and 2 ml of C ₆ D ₆ (previously purified by distillation over sodium) using a special technique that excludes air contact, are placed in a miniature glass autoclave and the solution is kept in solution with stirring under a pressure of synthesis gas of 1 MPa and a temperature of 45 ° C for 3 hours. After the autoclave is cooled, a sample is introduced into an ampoule for taking NMR spectra, previously filled with purified argon. The spectral data correspond to the complex HRh (CO) ₂ (A1); δ _H (ppm): - 10.26 (dt, 1H, ¹ J _Rh-H = 3.6 Hz, ² J _PH = 10.5 Hz, HRh), 1.11 (s, 18H, tC ₄ H ₉ ), 1.99 ( s, 18H, tC ₄ H ₉ ), 6.72-7.82 (m, 20H, Ar); δ _P (ppm): 172.7 (dd, ¹ J _Rh-P = 235 Hz, ² J _HP = 10.5 Hz). Resonance signals characteristic of a free polyphosphite ligand in the same solvent δp 145.4 (s); δ _H 1.39 (s, 18H, tC ₄ H ₉ ), 1.66 (s, 18H, tC ₄ H ₉ ) are not observed, which indicates its complete binding to the HRh (CO) ₂ (A1) complex. The synthesis is repeated by replacing 2 ml of deuterobenzene with 1.5 ml of mesitylene freshly distilled over sodium, the synthesis gas being bubbled through the solution for 4 hours at atmospheric pressure and heating to 55-60 ° C. In the ³¹ P NMR spectrum, only a single signal with δ _P 172.7 ppm (dd, ^l J _Rh-P = 235 Hz, ² J _HP = 10.5 Hz) is observed, and in the carbonyl region of the IR spectrum, absorption bands (cm ^-1 ) 2077 s ., 2031 from. and 1983 cf., and the absorption bands of the initial rhodium dicarbonylacetylacetonate (2081 and 2010 cm ^-1 ) are completely absent.

Together, the spectral data indicate the quantitative conversion of the starting material into the HRh (CO) ₂ (A1) complex.

In comparison with comparative example 1C, example 1 shows that if the solution contains phosphine in a molar ratio to rhodium 1: 1, when an equimolar mixture of a soluble rhodium compound and polyphosphite is synthesized by synthesis gas, HRh complexes are formed instead of HRh (CO) ₂ (A) complexes (CO) (A) (B), where A is polyphosphite, B is organophosphine.

Example 2

According to the invention, this example demonstrates the formation of complexes of the type HRh (CO) (A) (B), where A corresponds to polyphosphite A1 and B corresponds to phenyl diphenylphosphinite (Ph ₂ POPh). Rhodium dicarbonylacetylacetonate (19.31 mg, 0.075 mmol), polyphosphite A1 (62.71 mg, 0.075 mmol) and phenyl diphenylphosphinite (20.87 mg, 0.075 mmol) are dissolved under anaerobic conditions in 2 ml of mesitylene (previously purified by distillation over sodium) and at a temperature of 55- 60 ° C was bubbled through a synthesis gas solution for 4 hours. In the ³¹ P NMR spectra, complex multiplet signals are observed due to the mutual fission of three nonequivalent phosphorus nuclei in the complex HRh (CO) (A1) (Ph ₂ POPh), δp 173-180 ppm (2P, A1), 146-153 ppm (1P, Ph ₂ POPh). The presence of a signal in the hydride region of the ¹ H NMR spectrum (multiplet δ _H - 10.39 ppm) confirms the structure. In this case, the resonance signals of free polyphosphite A1 (δp 145.4 ppm) and phenyl diphenylphosphinite (δp 112 ppm) are not observed, and the integrated signal intensity of the HRh (CO) ₂ (A1) complex in the region of δ _P 172.7 ppm is 1-2% of the total number of nuclei ³¹ P, which indicates the almost complete binding of the ligands to the complex HRh (CO) (A1) (Ph ₂ POPh).

In comparison with comparative example 1C, example 2 shows that if the solution contains phosphinite in a molar ratio to rhodium 1: 1, when an equimolar mixture of a soluble compound of rhodium and polyphosphite is synthesized by synthesis gas, HRh complexes are formed instead of HRh (CO) ₂ (A) complexes (CO) (A) (B), where A is polyphosphite, B is organophosphinite.

Examples 3-9

These examples demonstrate the use of pre-synthesized complexes of the HRh (CO) (A) (B) type in the hydroformylation reaction, where A is polyphosphite (A = A1 - A4; formulas are given below), B is organophosphine or organophosphinite (indicated in the table).

Into a previously purged with argon miniature glass autoclave were placed 2 ml of freshly distilled over LiAlH ₄ benzene 0.03 mmol of rhodium dicarbonylacetylacetonate, 0.03 mmol of poly-phosphites A, 0.03 mmol of the ligand B - organofosfinita or organophosphines. The mixture is stirred under an excess pressure of synthesis gas of 0.1-1 MPa and a temperature of 45-50 ° C for 3 hours, after which the solvent and the resulting free acetylacetone are evaporated in vacuo under gentle heating in a water bath. The solid residue of the complex is quantitatively transferred to a 100 ml autoclave made of Hastelloy stainless steel, equipped with devices for thermostating (± 0.3 ° C) and mixing (1500 min ^-1 ). The autoclave is evacuated to a residual pressure of 0.05 Torr and 20 ml of p-xylene previously purified by distillation over sodium p-xylene are introduced into a thin steel capillary, purged with synthesis gas of composition СО: Н ₂ 1: 1 (3 × 15 atm), and the synthesis gas pressure is established 3 atm and heated to 90 ° C. After that, the pressure in the autoclave is released, 0.148 mol (about 12 ml) of liquid propylene is fed and the total pressure is quickly brought to 2 MPa by the supply of synthesis gas. Next, the pressure in the autoclave is kept constant using an electronic controller and the initial reaction rate is calculated from the pressure drop in the calibrated supply tank with synthesis gas. After 50 minutes, the autoclave is cooled, the yield of products and the regioselectivity of the reaction are determined by GLC.

Examples 10-13

The hydroformylation reaction on the previously synthesized HRh (CO) (A) (B) complexes is carried out analogously to examples 3-9, except that as

ligand B uses triphenylphosphine, varying the structure of the radicals in polyphosphite A (A = A5 - A8, the formulas are given below):

The results are presented in the table.

Comparative Example 2C

This example demonstrates the use of a complex of the HRh (CO) ₂ (A) type in a hydroformylation reaction of propylene, where A is a polyphosphite.

The complex HRh (CO) ₂ (A1) in a solution of benzene (2 ml) is synthesized analogously to comparative example 1C, starting from 7.74 mg (0.03 mmol) of rhodium dicarbonylacetylacetonate and 25.17 mg (0.03 mmol) of polyphosphite A1. Then, in an hydroformylation autoclave under anaerobic conditions, 18 ml of p-xylene, previously purified by distillation over sodium, are purged, purged with synthesis gas of composition СО: Н ₂ 1: 1 (3 × 15 atm), the synthesis gas pressure is set to 3 atm and heated to 90 ° C. After this, the pressure in the autoclave is released, using a technique that excludes contact with air, a solution of the synthesized complex HRh (CO) ₂ (A1) is introduced, then 0.148 mol (about 12 ml) of liquid propylene is fed, the total pressure is adjusted to 2 MPa by applying synthesis gas and carry out a hydroformylation reaction similarly to examples 3-9. The result is presented in the table. In comparison with examples 3-9, example 2C shows that in the case of complexes of the HRh (CO) ₂ (A) type, the regioselectivity of the reaction with linear aldehydes (S _n ) is significantly less than in the case of mixed complexes of the HRh (CO) (A) type ( B)

Comparative Example 3C

Hydroformylation of propylene is carried out on a HRh (CO) ₂ (A1) complex, as in Example 2C, with the exception that an additional amount (25.17 mg, 0.03 mmol) of polyphosphite A1 equal to its content in the complex is placed in a hydroformylation autoclave HRh (CO) ₂ (A1). The initial reaction rate was 28,400 mol of aldehyde / (mol Rh * h), regioselectivity S _n 91.3%. Compared with examples 3–9 and 2C, example 3C shows that, in the case of complexes of the HRh (CO) ₂ (A) type, even with a double consumption of the polyphosphite ligand, the regioselectivity S _n is lower than in the case of mixed polyphosphite – phosphine and polyphosphite – phosphinite complexes type HRh (CO) (A) (B).

Example 14

Hydroformylation of propylene is carried out analogously to example 4, except that instead of 0.03 mmol of the prepared hydride complex HRh (CO) (A1) (Ph ₂ POPh), 7.74 mg (0.03 mmol) of rhodium dicarbonylacetylacetonate were placed in a hydroformylation autoclave , 17 mg (0.03 mmol) of polyphosphite A1; and 8.34 mg (0.03 mmol) of phenyl diphenylphosphinite (Ph ₂ POPh). The initial reaction rate of 23,400 mol of aldehyde / mol Rh * h and regioselectivity S _{n of} 93.5% correspond to Example 4 with the previously synthesized complex HRh (CO) (A1) (Ph ₂ POPh) (table). Thus, Example 14 shows that complexes of the HRh (CO) (A) (B) type are formed from components under in situ hydroformylation conditions.

To compare the resistance of the type HRh (CO) (A) (B) and HRh (CO) ₂ (A) to the action of atmospheric oxygen, the following three examples are given.

Example 15

This example demonstrates the resistance of complexes of the HRh (CO) (A) (B) type (B = organophosphine) to the destruction of coordinated ligands under the action of oxygen. The synthesis of the HRh (CO) (A1) (Ph ₃ P) complex in a C ₆ D ₆ solution is carried out in a miniature glass autoclave as described in Example 1. The ³¹ P { ¹ H} NMR spectrum of the sample shows that about 99% of phosphorus atoms is in the complex HRh (CO) (A1) (Ph ₃ P), δ _P (ppm): 178.6 (m, 1P, ¹ J _Rh-P1 = 252 Hz, ² J _P2-P1 = 279 Hz, ² J _{Ph3P -P1} = 168 Hz, P1 in A1), 175.9 (m, 1P, ¹ J _Rh-P2 = 246 Hz, ² J _P1-P2 = 279 Hz, ² J _Ph3P-P2 = 146.5 Hz, P2 in A1) 35.9 (m, 1P, ¹ J _Rh-PPh3 = 140 Hz, ² J _P1-PPh3 = 168 Hz, ² J _P2-PPh3 = 146.5 Hz, Ph ₃ P); the molar ratio of the complex HRh (CO) (A1) (Ph ₃ P) to the impurity of the complex HRh (CO) ₂ (A1), found by the ratio of the resonance signals in the hydride region of the ¹ H NMR spectrum (δ _H - 10.44 and - 10.26 ppm, respectively) is about 50: 1. Next, the atmosphere in the autoclave is replaced with air and kept under an overpressure of 0.1 MPa and a temperature of 45 ° C for 1 hour. The ³¹ P { ¹ H} NMR spectrum shows that more than 93% of phosphorus atoms remain unchanged in the composition of the HRh (CO) (A1) (Ph ₃ P) complex, and the resonance signals of the impurity complex HRh (CO) ₂ (A1) δ _P 172.7 ppm (d, ¹ J _Rh-P = 235 Hz) and δ _H - 10.26 ppm (dt, ¹ J _Rh-H = 3.6 Hz, ² J _PH = 10.5 Hz) completely disappear.

Example 16

This example demonstrates the resistance of complexes of the HRh (CO) (A) (B) type (B is organophosphinite) to the destruction of coordinated ligands under the action of oxygen.

The synthesis of the HRh (CO) (A1) complex (Ph ₂ POPh) is carried out in a miniature glass autoclave as in Example 1, except that triphenylphosphine is replaced with an equivalent amount of phenyl diphenylphosphinite (Ph ₂ POPh). The ³¹ P { ¹ H} NMR spectrum of the sample shows that about 98% of the phosphorus atoms are in the complex HRh (CO) (A1) (Ph ₂ POPh). Next, the atmosphere in the autoclave is replaced with air and kept under an overpressure of 0.1 MPa and a temperature of 45 ° C for 1 hour. The ³¹ P { ¹ H} NMR spectrum indicates that more than 87% of the phosphorus atoms remain unchanged in the composition of the HRh (CO) (A1) (Ph ₂ POPh) complex.

Comparative Example 4C

This example demonstrates the sensitivity of complexes of the HRh (CO) ₂ (A) type to the destruction of the coordinated ligand under the influence of oxygen. The synthesis of the complex HRh (CO) ₂ (A1) in a solution of C ₆ D _{6 is} carried out in a miniature glass autoclave as described in example 1C. In the ³¹ P { ¹ H} NMR spectrum, there is a single resonant signal with δ _P 172.7 ppm (d, ¹ J _Rh-P = 235 Hz) corresponding to the phosphite groups of ligand A1 coordinated to the HRh (CO) ₂ (A1) complex. Next, the atmosphere in the autoclave is replaced with air and kept under an overpressure of 0.1 MPa and a temperature of 45 ° C for 1 hour. The ³¹ P NMR spectrum shows that more than 85% of the coordinated phosphite groups are oxidized to free phosphate groups with δ _P - 3.7 ppm.

This method allows you to create an effective hydroformylation catalyst that provides high processability with maximum selectivity for the most popular linear aldehydes and low consumption of expensive components.

Claims (2)

1. Hydride-carbonyl polyphosphite complex of rhodium with mixed organophosphorus ligands to catalyze the hydroformylation process of olefins of the general formula HRh (CO) (A) (B), where A is a polyphosphite ligand of the general formula:

,
in which k + m = 2, moreover, it is possible k = 0 or m = 0; X is a hydrocarbon radical comprising from 1 to 50 carbon carbon atoms; Z — identical or different hydrocarbon radicals in fragments m, comprising from 2 to 30 carbon atoms; Y are the same or different hydrocarbon radicals comprising from 1 to 30 carbon atoms; B is an organophosphorus ligand selected from organophosphine of the general formula (R1) (R2) (R3) P or organophosphinite of the general formula (R1) (R2) P (OR3), where R1, R2, R3 are hydrocarbon radicals comprising from 6 to 30 carbon atoms. 2. The method of obtaining the complex according to claim 1, which consists in the fact that rhodium dicarbonyl acetylacetonate, ligands A and B are dissolved in an equal molar ratio in a hydrocarbon solvent, after which the solution is treated with synthesis gas at a partial pressure of at least 0.1 MPa and temperature 30-120 ° C.