Organodiaryl selenoxides and process for preparation thereof

Abstract

Novel organodiaryl selenoxides and processes for preparation thereof, and use thereof as ligand in complexes.

Claims

1. An organodiaryl selenoxide compound of general structure (Ia) ##STR00026## where R.sup.2, R.sup.3, R.sup.4, R.sup.7, R.sup.8 and R.sup.9 in structure (Ia) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, O(C.sub.6-C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, where R.sup.5 and R.sup.6 in structure (Ia) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.2-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, O(C.sub.6-C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, COOH, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl group and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent is in each case independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, where R.sup.11 and R.sup.12 in each case in structure (Ia) are independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.8-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-O(C.sub.6-C.sub.20)-aryl, and CO(C.sub.1-C.sub.12)-alkyl, where the alkyl and aryl groups mentioned are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.8-C.sub.20)-aryl groups have at least one substituent and the at least one substituent is in each case independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl.

2. The compound according to claim 1 of general structure (Ib) ##STR00027## where R.sup.2, R.sup.4, R.sup.7 and R.sup.9 in structure (Ib) are (C.sub.1-C.sub.12)-alkyl, where R.sup.11 and R.sup.12 in structure (Ib) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-O(C.sub.6-C.sub.20)-aryl, and (CO)O(C.sub.1-C.sub.12)-alkyl, where the alkyl and aryl groups mentioned are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.8-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl.

3. The compound according to claim 1, wherein, in the organodiaryl selenoxide of the structures (Ia) R.sup.2, R.sup.3, R.sup.4, R.sup.7, R.sup.8 and R.sup.9 are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, O(C.sub.6-C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, and at least one radical of R.sup.2, R.sup.3, R.sup.4, R.sup.7, R.sup.8 and R.sup.9 in each case is independently selected from the group consisting of: (C.sub.6-C.sub.20)-aryl, O(C.sub.6-C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl.

4. The compound according to claim 1, wherein, in the organodiaryl selenoxide a) of the structure (Ia) or (Ib), R.sup.11 is the same as R.sup.12 and is selected from the group consisting of methoxymethyl-, benzyl-, and tert-butyl, or b) of the structure (Ia) or (Ib), R.sup.11 is selected from the group consisting of methoxymethyl-, benzyl-, and tert-butyl, and R.sup.12 is H, or c) of the structure (Ia) or (Ib), R.sup.12 is selected from the group consisting of methoxymethyl-, benzyl-, and tert-butyl, and R.sup.11 is H.

5. The compound according to claim 1, where R.sup.2, R.sup.3, R.sup.4, R.sup.7, R.sup.8, R.sup.9 are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, and O(C.sub.6-C.sub.20)-aryl.

6. The compound according to claim 1, where R.sup.5 and R.sup.6 are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.2-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, and O(C.sub.6-C.sub.20)-aryl.

7. The compound according to claim 1, where R.sup.2, R.sup.4, R.sup.7 and R.sup.9 are each independently selected from the group consisting of: (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, and O(C.sub.6-C.sub.20)-aryl.

8. The compound according to claim 1, where R.sup.2, R.sup.4, R.sup.7, R.sup.9 are each methyl- or tert-butyl- and R.sup.3, R.sup.5, R.sup.6, R.sup.8 are each H.

9. A process for preparing an organodiaryl selenoxide of the general structure (Ia), comprising the process step of (i) oxidizing an organodiaryl selenide of the general structure (IIa) ##STR00028## where R.sup.2, R.sup.3, R.sup.4, R.sup.7, R.sup.8 and R.sup.9 in structure (Ia) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, O(C.sub.6-C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C-.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, where R.sup.5 and R.sup.6 in structure (Ia) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.2-C.sub.12)-Alkyl, (C.sub.6-C.sub.20)-aryl, O(C.sub.6- C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, COOH, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, where R.sup.11 and R.sup.12 in each case in structure (Ia) are independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.1-C.sub.12)-Alkyl, (C.sub.6-C.sub.20)-aryl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-O(C.sub.6-C.sub.20)-aryl, and CO(C.sub.1-C.sub.12)-alkyl, where the alkyl and aryl groups mentioned are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, (ii) at least one compound of an organodiaryl selenoxide of the general structure (Ia) is obtained ##STR00029## where R.sup.2, R.sup.3, R.sup.4, R.sup.7, R.sup.8 and R.sup.9 in structure (Ia) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, O(C.sub.6-C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO-(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl group and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent is in each case independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, where R.sup.5 and R.sup.6 in structure (Ia) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, O(C.sub.6-C.sub.20)-aryl, -halogen, OCO(C.sub.1-C.sub.12)-alkyl, S-alkyl, S-aryl, COO(C.sub.1-C.sub.12)-alkyl, CONH(C.sub.1-C.sub.12)-alkyl, CO(C.sub.1-C.sub.12)-alkyl, CO(C.sub.6-C.sub.20)-aryl, COOH, SO.sub.3H, CN, and N[(C.sub.1-C.sub.12)-alkyl].sub.2, where the alkyl and aryl groups are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl group and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent is in each case independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl, where R.sup.11 and R.sup.12 in structure (Ia) are each independently selected from the group consisting of: H, (C.sub.1-C.sub.12)-alkyl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.1-C.sub.12)-alkyl, (C.sub.6-C.sub.20)-aryl, (C.sub.1-C.sub.12)-alkyl-O(C.sub.6-C.sub.20)-aryl, (C.sub.6-C.sub.20)-aryl-O(C.sub.6-C.sub.20)-aryl, and (CO)O(C.sub.1-C.sub.12)-alkyl, where the alkyl and aryl groups mentioned are each independently unsubstituted or substituted, where substituted (C.sub.1-C.sub.12)-alkyl groups and substituted (C.sub.6-C.sub.20)-aryl groups have at least one substituent and the at least one substituent in each case is independently selected from the group consisting of (C.sub.3-C.sub.12)-cycloalkyl, (C.sub.3-C.sub.12)-heterocycloalkyl, (C.sub.6-C.sub.20)-aryl, fluorine, chlorine, cyano, formyl, acyl, and alkoxycarbonyl.

10. The process according to claim 9, wherein (i) the oxidizing agent for oxidation of the organodiaryl selenide of the general structure (II) comprises N-chlorosuccinimide (CNS), bromosuccinimide (BNS), hydrogen peroxide, tert-butyl hypochlorite (tBuOCl), sodium hypochlorite (NaOCl) and/or meta-chlorobenzoic acid (mCPBA).

11. A complex comprising at least one organodiaryl selenoxide of claim 1 and at least one metal atom selected from the group consisting of Rh, Ru, Co, and Ir.

12. A process comprising the process steps of (i) initially charging at least one olefin, (ii) adding a complex according to claim 11, and a substance including a metal atom selected from the group consisting of: Rh, Ru, Co, and Ir, (iii) feeding in H.sub.2 and CO, (iv) heating the reaction mixture, wherein the olefin is converted to an aldehyde.

13. A process comprising the process steps of (i) initially charging at least one olefin, (ii) adding an organodiaryl selenoxide according to claim 1 and a substance including a metal atom selected from the group consisting of: Rh, Ru, Co, and Ir, (iii) feeding in H.sub.2 and CO, (iv) heating the reaction mixture, wherein the olefin is converted to an aldehyde.

Description

GENERAL METHODS

(1) Solvents and Reagents

(2) All reactions with moisture- and/or oxygen-sensitive substances were carried out in baked-out apparatuses under an argon atmosphere. Solvents for extraction and column chromatography were used at the following purities: dichloromethane (99.9%, Walter, Cat. No. BIE 073107033) ethyl acetate (99.5%, Walter, Cat. No. BIE 003917025) and n-hexane (95%, Walter (Baker), Cat. No. 8669). n-heptane (95%, Walter (Baker), Cat. No. 8662). Other solvents for extraction and column chromatography were of technical quality and were used without further purification unless otherwise stated. Dry solvents (abs.) were purified using a Pure Solv MD-7 System and stored under an argon atmosphere. Benzyl bromide was freshly distilled (17 mbar/82 C.) prior to use. Deuterated solvents were distilled from the drying agents specified: dichloromethane-d.sub.2 (phosphorus pentoxide), toluene-d.sub.8 (1. KOH; 2. sodium). Chemicals used for the syntheses were supplied by Sigma Aldrich, Alfa Aesar, Acros Organics, Avantor Performance Materials B.V., Merck KGaA and ABCR GmbH & Co. KG. These were used without further purification unless otherwise stated.

(3) Chromatographic Methods

(4) Column chromatography: Column chromatographic separations were carried out at elevated pressure (flash chromatography) on silica gel 60 230-400 mesh from Merck KGaA (particle size: 0.040-0.063 mm). The eluent mixtures used and the ratios by volume v/v are indicated in the specifications below. The following abbreviations apply to the eluents used: DCM (dichloromethane), EA (ethyl acetate), H (n-hexane) and Tol (toluene).

(5) Filtration: Filtrations for the removal of resulting solids were carried out using a G4 frit (pore width: 10-16 m).

(6) Analysis

(7) IR spectroscopy: IR spectra were recorded with a Nicolet 6700 FT-IR spectrometer from Thermo Electron. The substances were measured by ATR methods.

(8) .sup.1H NMR spectroscopy: .sup.1H NMR spectra were recorded with a model AV 300 (300 MHz) and with the model Fourier 300 (300 MHz) from Bruker. Chemical shifts are stated in units on the -scale. The residual proton signals of the solvent (dichloromethane-d.sub.2: =5.32 ppm, toluene-d.sub.8: =7.09; 7.00; 6.98; 2.09 ppm) served as standard.

(9) .sup.13C NMR spectroscopy: .sup.13C NMR spectra were recorded with models AV 300 (75 MHz) and Fourier 300 (75 MHz) from Bruker. The signal of the solvent (dichloromethane-d.sub.2: =54.0 ppm, toluene-d.sub.8: =137.9; 129.2; 128.3; 125.5; 20.4 ppm) served as internal standard wherein the chemical shifts were taken from the broadband .sup.1H-decoupled spectra.

(10) .sup.77Se NMR spectroscopy: .sup.77Se-NMR spectra were recorded with an AV 300 (57 MHz) from Bruker. The spectra were measured in broadband .sup.1H-decoupled mode. The chemical shifts are reported in ppm.

(11) Mass spectrometry: EI mass spectra were recorded on a Finnigan MAT 95-XP instrument from Thermo Electron and ESI-TOF mass spectra with a model 6210 Time-of-Flight LC/MS from Agilent.

(12) Autoclave Experiments of Rhodium-catalyzed Hydroformylation

(13) The hydroformylation was conducted in a 200 ml autoclave equipped with pressure-retaining valve, gas flow meter, sparging stirrer and pressure pipette from Premex Reactor AG, Lengau, Switzerland. The toluene used as solvent was purified using a Pure Solv MD-7 System and stored under argon. The 1-octene or n-octenes substrate (EVONIK Industries AG, octene isomer mixture of 1-octene: 3.3%; cis+trans-2-octene; 48.5%; cis+trans-3-octene: 29.2%; cis+trans-octene-4: 16.4%; structurally isomeric octenes: 2.6%) used as substrate was heated at reflux over sodium for several hours and distilled under argon.

(14) For the experiments, solutions of the catalyst precursor and the ligand were mixed in the autoclave under an argon atmosphere. [(acac)Rh(COD)] (Umicore, acac=acetylacetonate anion; COD=1,5-cyclooctadiene) was used as catalyst precursor. For experiments at a concentration of 100 ppm-m rhodium, 10 ml of a 4.31 mM solution was placed in the autoclave. Subsequently, the mass of ligand corresponding to a ratio L/Rh=5:1 (or 1:1) was dissolved and mixed in 10 ml of toluene. By adding further toluene, the starting volume of the catalyst solution was adjusted to 41.0 ml. Into a pressure-resistant pipette was filled: 1-octene or n-octenes (10.70 g). The autoclave was heated to the temperatures stated in each case at a total gas pressure (synthesis gas: Linde; H.sub.2 (99.999%): CO (99.997%)=1:1) of a) 42 bar for a final pressure of 50 bar or b) 12 bar for a final pressure of 20 bar with stirring (1500 rpm). After reaching the reaction temperature, the synthesis gas pressure was increased to a) 48.5 bar for a final pressure of 50 bar or b) 19.5 bar for a final pressure of 20 bar and the reactant was introduced under a positive pressure of about 3 bar set in the pressure pipette. The reaction was conducted at a constant pressure of 50 or 20 bar (closed-loop pressure controller from Bronkhorst, the Netherlands) respectively over 4 h. After the reaction time had elapsed, the autoclave was cooled to room temperature, decompressed while stirring and purged with argon. 1.0 ml of each reaction mixture was removed immediately after the stirrer had been switched off, diluted with 5.0 ml of pentane and analyzed by gas chromatography: HP 5890 Series II plus, PONA, 50 m0.2 mm0.5 m.

(15) Abbreviations: Bn=Benzyl; calc.=calculated; MOM=methylmethoxy; NCS=N-chlorosuccinimide; RT=room temperature

(16) General Procedure for Synthesis of the Precursors:

(17) General Procedure (GP1) for Preparation of Organodiaryl Selenides II as Selenodiphenols

(18) The appropriate phenols (1 equivalent) were added to a mixture of selenoxide (0.6 equivalent) in pyridine and stirred at 55-85 C. for 2-18 hours. Subsequently, the reaction mixtures were diluted with ethyl acetate and filtered, and the organic phases were washed with hydrochloric acid (10%) and water. After the organic phase had been removed, it was dried over magnesium sulphate and the solvent was distilled off under reduced pressure. The crude product of II was purified by column chromatography in each case.

Bis(3,5-dimethyl-2-hydroxyphenyl)selenium, IIb (1)

(19) ##STR00010##

(20) In a 250 ml round-bottom flask, 49.9 g of selenium dioxide (413 mmol) in 100 ml of pyridine were heated to 55 C. with the aid of an oil bath. Subsequently, 25 ml of 2,4-dimethylphenol (206 mmol) were added and the temperature was maintained for seven-and-a-half hours. On completion of the reaction, the mixture was diluted with 400 ml of ethyl acetate and filtered. The organic phase was washed with water and dried over magnesium sulphate. The pyridine was removed by distillation and the residue redissolved in ethyl acetate and washed with 10% hydrochloric acid and water in order to remove residues of pyridine. The organic phase was dried over magnesium sulphate and freed of the solvent under reduced pressure. The crude product thus obtained was heated under reflux in 400 ml of cyclohexane. After cooling to room temperature, the product crystallized. After one day, the product was filtered off, the filtrate was concentrated by half and again brought to crystallization at 4 C. 18.56 g, 58 mmol (56%) of fine, pale yellow flakes of the product were obtained.

(21) m.sub.p=120.1 C. (recrystallization from cyclohexane)

(22) .sup.1H NMR (400 MHz, CDCl.sub.3) =7.11-7.12 (m, 2H), 6.90-6.92 (m, 2H), 5.95 (br, 2H, OH), 2.23 (s, 6H), 2.19 (s, 6H); .sup.13C NMR (100 MHz, CDCl.sub.3) =152.04, 133.35, 133.30, 130.67, 124.42, 115.31, 20.45, 16.69; .sup.77Se NMR (76 MHz, CDCl.sub.3) =164.91; HRMS for C.sub.16H.sub.18O.sub.2.sup.80Se (ESI+) [M+Na.sup.+]: calculated: 345.0370, found: 445.0363;

(23) Elemental analysis for C.sub.16H.sub.18O.sub.2Se: calculated: C: 59.82%, H: 5.65%, found: C: 59.69%, H: 5.76%.

Di-(3-tert-butyl-2-hydroxy-5-methylphenyl)selenium, IIb (2)

(24) ##STR00011##

(25) As described in GP1, 0.80 g of 4-tert-butyl-2-methylphenol (4.9 mmol, 1.0 eq.) was added to a solution of 0.33 g of selenium dioxide (2.9 mmol, 0.6 eq.) in 6.7 ml of pyridine and the mixture was stirred at 55 C. for 56 hours. The reaction mixture was diluted with 50 ml of ethyl acetate and filtered, and washed three times with 50 ml each time of hydrochloric acid (10%) and once with 50 ml of sodium chloride solution. After drying over magnesium sulphate, the solvent was removed under reduced pressure and the residue obtained was purified by column chromatography (eluent: cyclohexane/ethyl acetate 99:1). Yield: 36%, 0.35 g, 0.9 mmol.

(26) m.sub.p=98.5 C.; .sup.1H NMR (400 MHz, CDCl.sub.3) =7.30 (d, .sup.4J=2.4 Hz, 2H), 7.11 (d, .sup.4J=2.4 Hz, 2H), 5.92 (s, 2H, OH), 2.26 (d, 6H), 1.23 (s, 18H); .sup.13C NMR (100 MHz, CDCl.sub.3) =151.78, 144.03, 129.83, 129.51, 123.89, 114.95, 34.18, 31.56, 16.99; HRMS for C.sub.22H.sub.30O.sub.2.sup.80Se (ESI+) [M+Na.sup.+]: calculated: 429.1309, found: 429.1250.

Bis(3,5-di-tert-butyl-2-hydroxyphenyl)selenium, IIb (3)

(27) ##STR00012##

(28) As described in GP1, 0.80 g of 2,4-di-tert-butylphenol (3.8 mmol, 1.0 eq.) was added to a solution of 0.25 g of selenium dioxide (2.3 mmol, 0.6 eq.) in 5.4 ml of pyridine and the mixture was stirred at 55 C. for 4 days. The reaction mixture was diluted with 50 ml of ethyl acetate and filtered, and washed three times with 50 ml each time of hydrochloric acid (10%) and once with 50 ml of sodium chloride solution. After drying over magnesium sulphate, the solvent was removed under reduced pressure and the residue obtained was purified by column chromatography (eluent: cyclohexane/ethyl acetate 99:1). The desired product was crystallized out of n-heptane at 4 C. Yield: 25%, 0.24 g, 0.5 mmol.

(29) m.sub.p=141.1 C. (recrystallization from heptane); .sup.1H NMR (400 MHz, CDCl.sub.3) =7.31 (d, .sup.4J=2.4 Hz, 2H), 7.29 (d, .sup.4J=2.4 Hz, 2H), 6.29 (s, 2H, OH), 1.42 (s, 18H), 1.24 (s, 18H);

(30) .sup.13C NMR (100 MHz, CDCl.sub.3) =151.7, 143.5, 135.8, 129.8, 125.6, 117.2, 35.4, 34.4, 31.6, 29.7; HRMS for C.sub.28H.sub.42O.sub.2.sup.80Se (ESI+) [M+Na.sup.+]: calculated: 513.2248, found: 513.2152.

Di(3-tert-butyl-5-ethyl-2-hydroxyphenyl)selenium, IIb (4)

(31) ##STR00013##

(32) As described in GP1, 2.00 g of 2-tert-butyl-4-ethylphenol (15.8 mmol, 1.0 eq.) was added to a solution of 1.06 g of selenium dioxide (9.5 mmol, 0.6 eq.) in 18 ml of pyridine and the mixture was stirred at 60 C. for 4 days. The reaction mixture was diluted with 50 ml of ethyl acetate and filtered, and washed three times with 50 ml each time of hydrochloric acid (10%) and once with 50 ml of sodium chloride solution. After drying over magnesium sulphate, the solvent was removed under reduced pressure and the residue obtained was purified by column chromatography (eluent: cyclohexane/ethyl acetate 99:1). Yield: 27%, 0.659 g, 1.5 mmol.

(33) m.sub.p=68.2 C.; .sup.1H NMR (400 MHz, CDCl.sub.3) =7.18 (d, .sup.4J=2.1 Hz, 2H), 7.07 (d, .sup.4J=2.1 Hz, 2H), 6.32 (s, 2H, OH), 2.51 (q, .sup.3J=7.6 Hz, 4H), 1.40 (s, 18H). 1.16 (t, .sup.3J=7.6 Hz, 6H).

(34) .sup.13C NMR (100 MHz, CDCl.sub.3) =152.00, 136.42, 136.32, 131.98, 128.22, 117.19, 35.09, 29.53, 28.12, 15.66; HRMS for C.sub.24H.sub.24O.sub.2.sup.80Se (ESI+) [M+Na.sup.+]: calculated: 457.1622, found: 457.1632; elemental analysis for C.sub.24H.sub.24O.sub.2Se: calculated: C: 66.50%, H: 7.38%, found: C: 66.26%, H: 7.54%.

Bis(3,5-di(1,1-dimethylpropyl)-2-hydroxyphenyl)selenium, IIb (5)

(35) ##STR00014##

(36) As described in GP1, 2.00 g of 2,4-di(1,1-dimethylpropyl)phenol (13.6 mmol, 1.0 eq.) was added to a solution of 0.91 g of selenium dioxide (8.2 mmol, 0.6 eq.) in 19 ml of pyridine and the mixture was stirred at 60 C. for 4 days. The reaction mixture was diluted with 50 ml of ethyl acetate and filtered, and washed three times with 50 ml each time of hydrochloric acid (10%) and once with 50 ml of sodium chloride solution. After drying over magnesium sulphate, the solvent was removed under reduced pressure and the residue obtained was purified by column chromatography (eluent: cyclohexane/ethyl acetate with a gradient from 100:0 to 95:5). Yield: 25%, 0.586 g, 1.1 mmol.

(37) m.sub.p=119.7 C.; .sup.1H NMR (400 MHz, CDCl.sub.3) =7.18 (d, .sup.4J=2.3 Hz, 2H), 7.11 (d, .sup.4J=2.3 Hz, 2H), 6.15 (s, 2H), 1.82 (q, .sup.3J=7.5 Hz, 4 H), 1.50 (q, .sup.3J=7.4 Hz, 4 H), 1.34 (s, 12H), 1.16 (s, 12H), 0.58 (q, .sup.3J=7.5 Hz, 12 H); .sup.13C NMR (100 MHz, CDCl.sub.3) =151.34, 142.32, 133.78, 130.15, 127.34, 116.99, 38.85, 37.45, 36.94, 33.11, 28.45, 27.72, 9.46, 9.01; HRMS for C.sub.22H.sub.30O.sub.2.sup.80Se (ESI+) [M+Na.sup.+]: calculated: 569.2874, found: 569.2800.

Synthesis of the Hydroxyl-Protected Selenodiphenols IIc (1a, 1b)

(38) ##STR00015##

EXAMPLE 1

(39) In a baked-out 25 ml Schlenk flask under an argon atmosphere, 2.0 eq of sodium hydride (60% in paraffin oil) were suspended in 3.0 ml of abs. DMF and cooled to 0 C. Subsequently, 1.0 eq of selenodiphenol IIb, dissolved in 2.0 ml of abs, DMF, was added dropwise. The resulting yellowish solution was stirred at 0 C. for 10 minutes and at RT for one hour. Subsequently, another 2.0 eq. of the halide were added at 0 C. and the mixture was stirred at 0 C. for 10 minutes, in the course of which cloudiness of the reaction mixture was observed. After a further 17 hours at RT, while cooling with ice, water (3.0 ml/1.0 mmol) was added and the resultant phases were separated. The aqueous phase was extracted with ethyl acetate (35.0 ml/1.0 mmol). The combined organic phases were washed with water (210 ml/1.0 mmol) and a saturated NaCl solution (210 ml/1.0 mmol) and dried over magnesium sulphate. The desiccant was filtered off and the solvent was removed under reduced pressure. The yellowish oil obtained was taken up in acetonitrile (5.0 ml/1.0 mmol) and admixed with n-heptane (2.5 ml/1.0 mmol). The phases were separated and the solvent was removed under reduced pressure. The crude product was dried at 50 C. under reduced pressure for three hours.

EXAMPLE 2

Synthesis of bis(2-(methoxymethoxy)-3,5-dimethylphenyl)selane IIc (1a)

(40) ##STR00016##

(41) According to Example 1, 81.0 mg (2.03 mmol, 2.0 eq, 60% in paraffin oil) of sodium hydride and 548 mg (1.70 mmol, 1.0 eq) of selenodiphenol IIb were reacted with 153 l (301 mg, 3.74 mmol, 2.0 eq) of chlorodimethyl ether. After extractive workup, 657 mg (1.60 mmol, 94%) of the title compound IIc (1a) were obtained as a pale yellow oil.

(42) IR (ATR): {circumflex over ()} (cm.sup.1)=2922; 2824; 2772; 1739; 1598; 1568; 1471; 1432; 1395; 1270; 1226; 1194; 1154; 1126; 1069; 951; 924; 849; 814; 796; 757; 727; 581; 540; 511; 477; 440;

(43) .sup.1H NMR (300 MHz, dichloromethane-d.sub.2): (ppm)=6.85 (dp, J=2.2 Hz, J=0.7 Hz, 2H, ArCH); 6.75 (dp, J=2.2 Hz, J=0.7 Hz, 2H, ArCH); 4.92 (s, 4H, OCH.sub.2CH.sub.3); 3.50 (s, 6H, OCH.sub.3); 2.22 (t, J=0.7 Hz, 6H, CH.sub.3); 2.09 (t, J=0.7 Hz, 6H, CH.sub.3); .sup.13C NMR (75 MHz, dichloromethane-d.sub.2): (ppm)=153.4; 135.2; 132.5; 132.1; 131.9; 125.0; 100.0; 57.85; 20.69; 17.25; .sup.77Se NMR (57 MHz, dichloromethane-d.sub.2): (ppm)=309.0; HR-MS (ESI-TOF): calc. for C.sub.20H.sub.26O.sub.4SeNa ([M+Na].sup.+): 433.08896, found: 433.08876; C.sub.20H.sub.26O.sub.4Se (410.10 g/mol).

EXAMPLE 3

Synthesis of bis(2-(benzyloxy)-3,5-dimethylphenyl)selane IIc (1b)

(44) ##STR00017##

(45) According to Example 1, 82.4 mg (2.06 mmol, 2.0 eq, 60% in paraffin oil) of sodium hydride and 331 mg (1.03 mmol, 1.0 eq) of selenodiphenol IIb were reacted with 244 l (352 mg, 2.06 mmol, 2.0 eq) of benzyl bromide. After extractive workup, 407 mg (0.810 mmol, 79%) of the title compound IIc (1b) were obtained as a pale yellow oil.

(46) IR (ATR): {circumflex over ()} (cm.sup.1)=3088; 3063; 3029; 2917; 2859; 2730; 1598; 1566; 1497; 1465; 1453; 1370; 1308; 1270; 1209; 1127; 1078; 978; 912; 848; 815; 776; 749; 725; 694; 601; 569; 513; 492; 466; .sup.1H NMR (300 MHz, dichloromethane-d.sub.2): (ppm)=7.42-7.30 (m, 4H, ArCH); 7.30-7.09 (m, 6H, ArCH); 6.90-6.68 (m, 4H, ArCH); 4.78 (s, 4H, OCH.sub.2Ph); 2.19 (s, 6H, CH.sub.3); 2.10 (t, J=0.7 Hz, 6H, CH.sub.3); .sup.13C NMR (75 MHz, dichloromethane-d.sub.2): (ppm)=154.5; 138.0; 135.2; 132.6; 132.0; 131.9; 128.7; 128.5; 128.3; 125.1; 74.77; 20.86; 1677; .sup.77Se-NMR (57 MHz, dichloromethane-d.sub.2): (ppm)=299.2; .sup.77Se-NMR (57 MHz, toluene-d.sub.8): (ppm)=302.6; MS (ESI-TOF): m/z=525.130 ([M+Na].sup.+); 541.124 ([M+K].sup.+); HR-MS (ESI-TOF): calc. for C.sub.30H.sub.30O.sub.2SeNa ([M+Na].sup.+); 525.13053, found: 525.12986; C.sub.30H.sub.30O.sub.2Se (502.14 g/mol).

(47) Both bis(3,5-dimethyl-2-hydroxyphenyl)selenium, di-(3-tert-butyl-2-hydroxy-5-methyl-phenyl)selenium; bis(3,5-di-tert-butyl-2-hydroxyphenyl)selenium; di(3-tert-butyl-5-ethyl-2-hydroxyphenyl)selenium; bis(3,5-di(1,1-dimethylpropyl )-2-hydroxyphenyl)selenium; bis(3-tert-butyl-5-methyl-2-hydroxyphenyl)selenium, bis(3,3,5,5-tetra-tert-butyl-2-hydroxyphenyl)selenium can be converted analogously to Examples 1 to 3 to the corresponding bis(2-(methoxymethoxy)- or bis(2-(benzyloxy)-substituted selenes of the general structure II.

(48) Mono-protection of the Selenodiphenol

EXAMPLE 4

Synthesis of 2-((2-(benzyloxy)-3,5-dimethylphenyl)selanyl)-4,6-dimethylphenol IIc

(49) ##STR00018##

(50) In a baked-out 25 ml Schlenk flask under an argon atmosphere, 40.2 mg (1.01 mmol, 1.0 eq, 60% in paraffin oil) of sodium hydride were suspended in 3.0 ml of abs. THF and cooled to 0 C. Subsequently, 324 mg (1.01 mmol, 1.0 eq) of selenodiphenol IIb, dissolved in 2.0 ml of abs. THF, were added dropwise. The yellowish solution was stirred at 0 C. for 15 minutes and at RT for two hours. Subsequently, at 0 C., 119 l (172 mg, 1.01 mmol, 1.0 eq) of benzyl bromide were added and the mixture was stirred at 0 C. for 30 minutes. After a further 16 hours at RT, the solvent was removed under reduced pressure. 391 mg of the reaction mixture of 2-((2-(benzyloxy)-3,5-dimethylphenyl)selanyl)-4,6-dimethylphenol IIc (1b*) (314 mg, 0.762 mmol, 76%) and bis(2-(benzyloxy)-3,5-dimethylphenyl)selane IIc (1b) (76.6 mg, 0.152 mmol, 15%) in a ratio of 4.96:1 (determined from crude .sup.1H NMR spectrum) were obtained. By means of purification by column chromatography (100% H .fwdarw.100:1 .fwdarw.50:1 .fwdarw.20:1 .fwdarw.10:1 H/DCM) it was possible to obtain 51.0 mg of compound IIc (1b*), which was subsequently characterized as follows:

(51) ##STR00019##

(52) IR (ATR): {circumflex over ()} (cm.sup.1)=3409; 3030; 3011; 2919; 2854; 2730; 1567; 1497; 1467; 1372; 1328; 1284; 1268; 1251; 1231; 1208; 1123; 1078; 1010; 976; 912; 858; 814; 763; 749; 725; 695; 602; 570; 516; 491; 461; .sup.1H-NMR (300 MHz, toluene-d.sub.8): (ppm)=7.62-7.43 (m, 2H, ArCH); 7.36-7.29 (m, 1H, ArCH); 7.28-7.08 (m, 2H, ArCH); 6.86-6.66 (m, 3H, ArCH); 6.58 (d, J=2.1 Hz, 1H, ArCH); 4.82 (s, 2H, OCH.sub.2Ph); 2.27 (s, 3H, CH.sub.3); 2.12 (d, J=2.4 Hz, 3H, CH.sub.3); 2.07 (s, 3H, CH.sub.3); 1.86 (s, 3H, CH.sub.3); .sup.13C-NMR (75 MHz, toluene-d.sub.8): (ppm)=154.2; 153.2; 137.7; 136.0; 135.1; 134.6; 131.3; 131.2; 129.7; 129.0; 128.6; 128.3; 128.2; 128.1; 74.94; 30.30; 20.53; 20.18; 16.93; 16.31; .sup.77Se-NMR (57 MHz, toluene-d.sub.8): (ppm)=207.3; HR-MS (ESI-TOF): calc. for C.sub.23H.sub.25O.sub.2Se ([M+H].sup.+): 413.10155, found: 413.10109; calc. for C.sub.23H.sub.24O.sub.2SeNa ([M+Na].sup.+): 435.0835, found: 435.08378; C.sub.23H.sub.24O.sub.2Se (412.09 g/mol).

(53) The oxidation of diphenyl selenide IV under the conditions described is known from the literature; the other oxidations were conducted in an analogous manner.

(54) ##STR00020##

Synthesis of the Organodiaryl Selenoxide Compounds

(55) ##STR00021##

(56) GP 2: In a 50 ml two-neck flask, 1.0 eq. of the organodiphenyl selenide II compound was dissolved in a 1:1 mixture of dichloromethane/methanol (13.4 ml/1.0 mmol) and cooled to 0 C. Subsequently, 1.05 eq. of N-chlorosuccinimide were added and the mixture was stirred at 0 C. for 30 minutes, in the course of which a pale yellow color of the solution was observed. Subsequently, a saturated NaHCO.sub.3 solution (1.0 ml/1.0 mmol) was added, the mixture was stirred for 15 minutes, water (15 ml/1.0 mmol) was added and the mixture was stirred once again at 0 C. for 15 minutes. And the organic phase was washed with water (325 ml/1.0 mmol). The aqueous phase was extracted with dichloromethane (325 ml/1.0 mmol) and dried over magnesium sulphate. The desiccant was filtered off, the solvent was removed under reduced pressure and the crude product was dried under vacuum at 50 C. for three hours.

a) Synthesis of Seleninyldibenzene III (Comparative Example)

(57) ##STR00022##

(58) According to GP 2, 175 l (234 mg, 1.00 mmol, 1.0 eq) of diphenyl selenide were reacted with 140 mg (1.05 mmol, 1.05 eq) of N-chlorosuccinimide. After extractive workup, 235 mg (0.940 mmol, 94%) of the title compound III were obtained as a colourless solid.

(59) IR (ATR): {circumflex over ()} (cm.sup.1)=3044; 3008; 2989; 2941; 1570; 1470; 1437; 1300; 1156; 1069; 1056; 1047; 1017; 993; 915; 850; 820; 733; 686; 611; 481; 442, .sup.1H NMR (300 MHz, toluene-d.sub.8): (ppm)=7.67-7.51 (m, 4H, ArCH); 7.16-6.87 (m, 6H, ArCH); .sup.13C NMR (75 MHz, toluene-d.sub.8): (ppm)=145.1; 130.5; 129.3; 126.0; .sup.77Se NMR (57 MHz, toluene-d.sub.8): (ppm)=851.0; HR-MS (ESI-TOF): calc. for C.sub.12H.sub.11OSe ([M+H].sup.+): 250.99700, found: 250.99691; calc. for C.sub.12H.sub.10OSeNa ([M+Na].sup.+): 272.97894, found: 272.97888; C.sub.12H.sub.10OSe (249.99 g/mol). The analytical data are in agreement with the literature data.

b) 2-(Benzyloxy)-1-((2-(methoxymethoxy)-3,5-dimethylphenyl)seleninyl)-3,5-dimethylbenzene Ic (1a)

(60) ##STR00023##

(61) According to GP 2, 407 mg (0.991 mmol, 1.0 eq) of bis(2-(methoxymethoxy)-3,5-dimethylphenyl)selane IIc (1a) were reacted with 139 mg (1.04 mmol, 1.05 eq) of N-chlorosuccinimide. After extractive workup, 397 mg (0.932 mmol, 94%) of the title compound Ic (1a) were obtained as a colorless solid.

(62) .sup.1H NMR (300 MHz, dichloromethane-d.sub.2): (ppm)=7.27-7.17 (m, 2H, ArCH); 7.12 (td, J=1.4, 0.7 Hz, 2H, ArCH); 5.02 (d, J=1.1 Hz, 4H, OCH.sub.2OCH.sub.3); 3.59 (s, 6H, OCH.sub.3); 2.29 (d, J=0.7 Hz, 6H, 5-CH.sub.3); 2.28 (t, J=0.6 Hz, 6H, 3-CH.sub.3); .sup.13C NMR (75 MHz, dichloromethane-d.sub.2): (ppm)=152.3; 137.1; 135.7; 131.6; 125.6; 100.7; 58.14; 0.94; 16.84; .sup.77Se NMR (57 MHz, toluene-d8): (ppm)=831.0 ppm; C.sub.20H.sub.26O.sub.5Se (426.09 g/mol).

c) Synthesis of 6,6-seleninylbis 1-(benzyloxy)-2,4-dimethylbenzene Ic (1b)

(63) ##STR00024##

(64) According to GP 2, 185 mg (0.369 mmol, 1.0 eq) of bis(2-(benzyloxy)-3,5-dimethylphenyl)selane IIc (1b) were reacted with 51.7 mg (1.05 mmol, 1.05 eq) of N-chlorosuccinimide. After extractive workup, 143 mg (0.276 mmol, 75%) of the title compound Ic (1b) were obtained as a colorless solid.

(65) IR (ATR): {circumflex over ()} (cm.sup.1)=3376; 3089; 3062; 3031; 3004; 2953; 2920; 2853; 2734; 1588; 1467; 1374; 1364; 1270; 1233; 1219; 1207; 1196; 1116; 1080; 1041; 916; 863; 842; 824; 777; 748; 725; 696; 600; 567; 524; 514; 495; 464; .sup.1H-NMR (300 MHz, toluene-d8): (ppm)=7.46 (d, J=2.2 Hz, 1H, ArCH); 7.12-7.03 (m, 4H, ArCH); 6.98-6.87 (m, 4H, ArCH); 6.83 (p, J=1.1 Hz, 1H, ArCH); 6.81-6.77 (m, 2H, ArCH); 6.49 (d, J=2.0 Hz, 2H, ArCH); 4.57 (d, J=11.2 Hz, 2H, CHHPh); 4.39 (d, J=11.3 Hz, 2HCHHPh); 1.79 (s, 6H, 5-CH.sub.3); 1.75 (s, 6H, 3-CH.sub.3); .sup.13C-NMR (75 MHz, toluene-d.sub.8): (ppm)=154.0; 138.0; 135.5; 135.0; 131.2; 128.4; 128.1; 127.9; 126.6; 125.6; 76.05; 20.58; 16.00; .sup.77Se-NMR (57 MHz, toluene-d.sub.8): (ppm)=834.2 ppm; HR-MS (ESI-TOF): calc. for C.sub.30H.sub.31O.sub.3Se ([M+H].sup.+): 519.14351, found: 519.14372; calc. for C.sub.30H.sub.30O.sub.3SeNa ([M+Na].sup.+): 541.12545, found: 541.12524; C.sub.30H.sub.30O.sub.3Se (518.14 g/mol).

(66) CatalysisHydroformylation

(67) ##STR00025##

(68) TABLE-US-00001 TABLE 1 Details of the catalysis experiments using noninventive organoselenium compounds Entry Ligand Olefin/solvent Rh/ligand/olefin ratio p [bar] T [ C.] t [h] Y [%] S [%] 1 IIb n-octene/toluene 1:1:2197 50 120 4 9.5 33.2 (100 ppm Rh) 2 III n-octene/toluene 1:1:2205 50 120 4 89.5 28.1 (40 ppm Rh) 3* 1a n-octene/toluene 1:1:2203 50 120 4 96.1 28.1 (100 ppm Rh) 4* 1b n-octene/toluene 1:1:2215 50 120 4 96.7 28.4 (100 ppm Rh) Notes for Table 1: p = pressure, T = temperature, t = time, Y = yield; S = n-regioselectivity, *= inventive

(69) Rhodium-catalyzed hydroformylation with an unprotected selenodiphenol IIb (Entry 1) leads to a low yield of 9.5% (retention of 90.5% residual olefin) and an n-regioselectivity of 33.2%.

(70) Catalysis experiment 2) illustrates the successful use of the unsubstituted diphenyl selenoxide compound in rhodium-catalysed hydroformylation.

(71) Through use of the organodiphenyl selenoxide III, a high yield of 89.5% in hydroformylation with n-octene was recorded.

(72) By comparison, it was possible to enhance the yields further in experiments 3) and 4), with the same good selectivity. The use of the inventive ligands 1a and 1b thus leads to a higher yield of product of value. A maximum yield is essential for the economic viability of processes on the industrial scale, since it is possible in this way to achieve the greatest possible creation of value from the raw materials.

(73) The stated object was thus achieved using the inventive ligands 1a and 1b.