Bis-phosphites with naphthol flanking structural units

Abstract

Bis-phosphites with naphthol flanking structural units and their use in hydroformylation.

Description

TECHNICAL FIELD

[0001] The present invention relates to bisphosphites having naphthol wing structure units and their use in hydroformylation. BACKGROUND

[0002] Phosphorus-containing compounds as ligands play an essential role in a variety of reactions, for example in hydrogenation, hydrocyanation and hydroformylation.

[0003] WO 02 / 00670 A1 describes bisphosphite compounds, metal complexes thereof and the use of the compounds and complexes in the hydroformylation of olefins. Inter alia, the compound (IIa) is disclosed therein:

[0004] SUMMARY

[0005] It is a technical object of the present invention to provide a compound which enables good yields in the hydroformylation of olefins.

[0006] This object is achieved by a compound according to claim 1.

[0007] The compound according to formula (I) or (II):

[0008]

[0009] wherein R 1 is -(Ci-C6)-alkyl.

[0010] In one embodiment, R 1 is -CH3or - t Bu.

[0011] In one embodiment, R 1 is - t Bu.

[0012] In one embodiment, the compound is a compound according to formula (I). In one embodiment, the compound has the structure (1):

[0013]

[0014] In one embodiment, the compound is a compound according to formula (II).

[0015] In one embodiment, the compound has the structure (2):

[0016]

[0017] In addition to the compounds themselves, methods of using the above-mentioned compounds are claimed.

[0018] The process comprises the following process steps:

[0019] a) pre-charge with an olefin;

[0020] b) addition of the compound described above;

[0021] c) addition of a Rh-containing substance;

[0022] d) admission of H2 and CO;

[0023] e) heating of the reaction mixture formed from a) to d), wherein the olefin is converted into an aldehyde.

[0024] In one variant of the process, the Rh-containing substance is selected from the group consisting of Rh(acac)(CO)2, Rh(acac)(cod) (Umicore, acac = acetylacetonate anion; cod = 1,5-cyclooctadiene), Rh4CO 12 .

[0025] In one variant of the process, the Rh-containing substance is Rh(acac)(CO)2. DETAILED DESCRIPTION

[0026] The application will be explained in more detail below with reference to working examples.

[0027] Synthesis

[0028] First stage

[0029]

[0030] 0.076 mol of naphthalene-1,8-diol was dried with an oil pump vacuum at 50°C overnight. The following day, the Schlenk flask was filled with argon and the naphthalene-1,8-diol was dissolved in 350 ml of dry toluene. In a Schlenk flask that was repeatedly evacuated and filled with inert gas (sekurierten), 0.114 mol of phosphorus trichloride was dissolved in 120 ml of dry toluene. Subsequently, the naphthalene-1,8-diol solution was slowly and steadily added to the PCl3 solution at -20°C. Afterwards, 0.165 mol of triethylamine was slowly added to the solution at -20°C under high-speed stirring. The solution was brought to room temperature and stirring was continued overnight. The following day, the reaction mixture was filtered using a glass frit, the filter cake was washed twice with 25 ml of toluene each time and the filtrate was concentrated at 40°C by oil pump vacuum.

[0031] Yield: 86%

[0032] Second stage

[0033]

[0034] Under an inert gas atmosphere, 0.016 mol of the bisphenol was weighed into a Schlenk flask, which was vacuum dried overnight with an oil pump and filled with argon the next morning. The bisphenol was dissolved in 40 ml of toluene. Under an inert gas atmosphere, 0.016 mol of the chlorophosphite was weighed into a Schlenk flask, dissolved in 40 ml of toluene and mixed with 0.016 mol of degassed triethylamine. The chlorophosphite-toluene solution was added dropwise to the bisphenol solution at room temperature over a period of 1 hour and stirred at 40°C for 24 hours. The reaction mixture was filtered with a glass frit, and the filter cake was washed twice with 20 ml of toluene each time. The resulting filtrate was concentrated and dried at 40°C under oil pump vacuum.

[0035] Yield: 75%

[0036] Third stage

[0037]

[0038] Under an inert gas atmosphere, 11.9 mmol of the monophosphite was dissolved in 150 ml of dry toluene and 29.8 mmol of degassed triethylamine. In a Schlenk flask, which was repeatedly evacuated and filled with inert gas, 14.9 mmol of phosphorus trichloride was dissolved in 100 ml of dry toluene and cooled to 0°C. The organochlorophosphite-triethylamine solution was then added to the phosphorus trichloride solution at 0°C. The reaction mixture was stirred at room temperature for 24 hours. The resulting ammonium hydrochloride was filtered off with a glass frit and washed twice with 50 ml of dry toluene each time. Subsequently, the resulting filtrate was concentrated to dryness at 45°C under oil pump vacuum.

[0039] Yield: 87%

[0040] Synthesis (1)

[0041]

[0042] Under an inert gas atmosphere, 2.9 mmol of the organodichlorophosphite was suspended in 30 ml of dry toluene. 6.7 mmol of the naphthol was weighed into a Schlenk flask, which was repeatedly evacuated and filled with inert gas for a short time with the aid of an oil pump vacuum. Subsequently, the Schlenk flask was filled with argon, the naphthol was dissolved in 20 ml of dry toluene and 14.3 mmol of degassed triethylamine was added. Subsequently, the naphthol solution was slowly and steadily added to the chlorophosphite suspension at room temperature. The reaction solution was stirred at room temperature overnight. The resulting ammonium hydrochloride was filtered off with a glass frit and washed twice with 10 ml of dry toluene each time. Subsequently, the resulting filtrate was concentrated to dryness at 40°C with the aid of an oil pump vacuum. The dried filtrate was purified by column chromatography.

[0043] Yield: 81%

[0044] Compounds (2) to (4) and (lla) are prepared in an analogous manner to compound (1).

[0045] Compounds (3), (4) and (lla) are comparative compounds not according to the application.

[0046]

[0047] Catalytic experiments

[0048] The reaction vessel was dried beforehand under temperature (80°C) and oil pump vacuum. The liquid substances were degassed by argon sparging for at least 15 minutes. The hydroformylation reaction was carried out in a 0.5 litre autoclave from Berghof Products+Instruments GmbH equipped with a constant pressure device. The reactor was heated with an oil bath from IKA. The reactor was used for gas exchange and as temperature control device. Five glass vials (20 ml) with catalyst solution and magnetic stirrer and sparging under argon were placed into the reactor, enabling gas exchange between vial and reactor space. The temperature of the glass vials was controlled by the heat conducting oil in the reactor. The reaction temperature indicated was measured in the glass vials. As substrate n-octene (Oxeno GmbH, mixture of octene isomers, 1-octene: 3%; cis + trans-2-octene: 49%; cis + trans-3-octene: 29%; cis + trans-4-octene: 16%; structurally isomeric octenes: 3%) was used.

[0049] For the experiments, stock solutions were prepared beforehand under argon atmosphere. For this, 0.0127 g of Rh(acac)(CO)2 and the corresponding amount of phosphite compound (MV Lig: Rh = 5:1) were weighed out and filled up with 48.0 ml of toluene. About 8 ml of this solution were divided into vials in each case and the exact amount was weighed out. The vials were placed into the reactor and closed. Three times with argon sparging, three times with synthesis gas (Linde; H2(99.999%): CO (99.997%) = 1 :1) sparging. After the pressure test was complete, the autoclave was heated to the desired temperature of 120°C under stirring (900 revolutions per minute) at a total pressure of 10 bar. After the reaction temperature was reached, the synthesis gas pressure was increased to 20 bar and 2 ml of substrate were metered in separately with an HPLC pump to start the reaction. A rhodium concentration of 100 ppm resulted therefrom. After 1 hour of reaction start under constant pressure, samples were taken from each vial and analysed by gas chromatography in undiluted state: HP 6890, DH 150, 150 m x 0.25 mm x 1 μm. Quantitative analysis of residual olefins and aldehydes was carried out with toluene as internal standard. The results listed in the table below are the average of a single experiment.

[0050] Catalytic experiment results

[0051] [Rh]: 100 ppm, p: 20 bar, T: 120°C; t: 1 hour

[0052] Table 1 (R 1 t Bu):

[0053] ligand yield [%] (1)* 56 (2)* 48

[0054] * working example according to the invention

[0055] Table 2 (R 1

[0056] ligand yield [%] (3) 36 (4) 28 (IIa) 39

[0057] The experiments carried out demonstrate that the compounds according to the invention achieve the proposed object.​​

Claims

1. Compounds according to formula (I) or (II): Where R 1 It is -(C1-C6)-alkyl.

2. The compound according to claim 1, Where R 1 -CH3 or - t Bu.

3. The compound according to claim 1 or 2, Where R 1 for- t Bu.

4. The compound according to any one of claims 1 to 3, wherein the compound is a compound according to formula (I).

5. The compound according to any one of claims 1 to 4, wherein the compound has structure (1):

6. The compound according to any one of claims 1 to 3, The compound mentioned therein is a compound according to formula (II).

7. The compound according to any one of claims 1 to 3, The compound described above has structure (2):

8. The method, including the following method steps: a) Pre-insertion of olefins; b) Add the compound according to any one of claims 1 to 7; c) Add substances containing Rh; d) Introduce H2 and CO; e) Heat the reaction mixture formed from a) to d), wherein the olefin is converted into an aldehyde.

9. The method according to claim 8, The Rh-containing substances are selected from: Rh(acac)(CO)2, Rh(acac)(cod) (Umicore, acac = acetylacetone anion; cod = 1,5-cyclooctadiene), Rh4CO 12 .

10. The method according to claim 8 or 9, The substance containing Rh is Rh(acac)(CO)2.

Images