Process for hydroformylation of olefins using Pt and bromine

Abstract

Process for hydroformylation of olefins using Pt and bromine.

Claims

1. Process comprising the process steps of: a) initially charging an olefin; b) adding a compound of formula (I): ##STR00008## where R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8 are selected from: —H, —(C.sub.1-C.sub.12)-alkyl, —(C.sub.6-C.sub.20)-aryl; and, if R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6, R.sup.7, R.sup.8 are —(C.sub.6-C.sub.20)-aryl, the aryl ring may have substituents selected from: —(C.sub.1-C.sub.12)-alkyl, —O—(C.sub.1-C.sub.12)-alkyl; c) adding a Pt compound capable of forming a complex; d) adding a bromine compound; e) feeding in CO and H.sub.2; f) heating the reaction mixture from steps a) to e), to convert the olefin to an aldehyde.

2. Process according to claim 1, where R.sup.2, R.sup.3, R.sup.5, R.sup.6, R.sup.7, R.sup.8 are selected from: —(C.sub.1-C.sub.12)-alkyl, —(C.sub.6-C.sub.20)-aryl.

3. Process according to claim 1, where R.sup.5, R.sup.6, R.sup.7, R.sup.8 are —(C.sub.6-C.sub.20)-aryl.

4. Process according to claim 1, where R.sup.2 and R.sup.3 are —(C.sub.1-C.sub.12)-alkyl.

5. Process according to claim 1, where R.sup.1 and R.sup.4 are each —H.

6. Process according to claim 1, wherein the compound (I) has the structure (1): ##STR00009##

7. Process according to claim 1, wherein the Pt compound is selected from: Pt(II)Br.sub.2, Pt(IV)Br.sub.4, diphenyl(1,5-COD)Pt(II), Pt(II)(acac).sub.2, Pt(0)(PPh.sub.3).sub.4, Pt(0)(DVTS) solution (CAS: 68478-92-2), Pt(0)(ethylene)(PPh.sub.3).sub.2, Pt(II)Br.sub.2(COD), tris(benzylideneacetone)Pt(0), Pt(II)(OAC).sub.2 solution, Pt(0)(t-Bu).sub.2, Pt(II)(COD)Me.sub.2, Pt(II)(COD)I.sub.2, Pt(IV)IMe.sub.3, Pt(II)(hexafluoroacetylacetonate).sub.2.

8. Process according to claim 1, wherein the Pt compound is selected from: Pt(II)Br.sub.2, Pt(II)(acac).sub.2.

9. Process according to claim 1, wherein the bromine compound is selected from: Pt(II)Br.sub.2, LiBr.

10. Process according to claim 1, wherein the bromine compound is added in an amount in the range of 0.1 to 10, measured in equivalents based on Pt.

11. Process according to claim 1, comprising the additional process step e′): e′) adding a solvent.

12. Process according to claim 11, wherein the solvent is selected from: THF, DCM, ACN, DMF, toluene, texanol, pentane, hexane, octane, isooctane, decane, dodecane, cyclohexane, benzene, xylene, Marlotherm, propylene carbonate, MTBE, diglyme, triglyme, diethyl ether, dioxane, isopropanol, tert-butanol, isononanol, isobutanol, isopentanol, ethyl acetate.

13. Process according to claim 1, wherein CO and H.sub.2 are fed in at a pressure in a range from 1 MPa (10 bar) to 6 MPa (60 bar).

14. Process according to claim 1, wherein the reaction mixture is heated to a temperature in the range from 25° C. to 150° C.

15. Process according to claim 1, wherein the olefin is selected from: ethene, propene, 1-butene, cis- and/or trans-2-butene, isobutene, 1,3-butadiene, 1-pentene, cis- and/or trans-2-pentene, 2-methyl-1-butene, 3-methyl-1-butene, 2-methyl-2-butene, hexene, tetramethylethylene, heptene, 1-octene, 2-octene, di-n-butene, or mixtures thereof.

Description

EXPERIMENTAL DESCRIPTION

[0041] A vial was charged with PtX.sub.2 (X=halogen), ligand, and an oven-dried stirrer bar. The vial is then sealed with a septum (PTFE-coated styrene-butadiene rubber) and phenolic resin cap. The vial is evacuated and refilled with argon three times. Toluene and olefin were added to the vial using a syringe. The vial was placed in an alloy plate, which was transferred to an autoclave (300 ml) of the 4560 series from Parr Instruments under an argon atmosphere. After purging the autoclave three times with CO/H.sub.2, the synthesis gas pressure was increased to 40 bar at room temperature. The reaction was conducted at 120° C. for 20 h/18 h. On termination of the reaction, the autoclave was cooled to room temperature and cautiously decompressed. Yield and selectivity were determined by GC analysis.

[0042] Hydroformylation of 1-octene

##STR00003##

[0043] Reaction conditions:

[0044] 20 mmol of 1-octene, 1.0 mol % Pt, 2.2 equivalents of Xantphos (1), solvent: toluene, p(CO/H.sub.2): 40 bar, T: 120° C., t: 20 h.

[0045] Yields:

[0046] PtBr.sub.2: 99%

[0047] PtCl.sub.2: 30%

[0048] Variation of the Halogen (2-octene)

##STR00004##

[0049] Reaction conditions:

[0050] 20 mmol of 2-octene, 1.0 mol % Pt, 1.1 equivalents of Xantphos (1), solvent: toluene, p(CO/H.sub.2): 40 bar, T: 120° C., t: 20 h.

[0051] Yields:

[0052] PtBr.sub.2: 99%

[0053] PtCl.sub.2: 16%

[0054] Variation of the Halogen (1-octene)

[0055] Reaction conditions:

[0056] 10.0 mmol of 1-octene, 0.1 mol % PtX.sub.2, 2.2 equivalents of ligand, solvent: toluene, p(CO/H.sub.2): 40 bar, T: 120° C., t: 20 h.

[0057] Yields:

TABLE-US-00001 Ligand Halogen Yield [%] [00005] Br/Cl 97/5

[0058] Variation of the Ligand and of the Halogen

[0059] Reaction conditions:

[0060] 1.0 mmol of 2-octene, 0.5 mol % PtX.sub.2, 2.0 equivalents of ligand, solvent: toluene, p(CO/H.sub.2): 40 bar, T: 120° C., t: 18 h.

[0061] Yields:

TABLE-US-00002 Ligand Halogen Yield [%] [00006] Br/Cl 85/<1 [00007] Br/Cl 81/<1

[0062] Variation of the Equivalents and of the Halogen

[0063] Reaction conditions:

[0064] 1.0 mmol of 1-octene, 1.0 mol % Pt(acac).sub.2, LiX (X=halogen), 2.2 equivalents of Xantphos (1), solvent: toluene, p(CO/H.sub.2): 40 bar, T: 120° C., t: 20 h.

TABLE-US-00003 Equivalents of LiX X Yield [%] 0.5 Br 68 2.0 Br 71 1.5 Cl 0 4.0 Cl 0

[0065] As the experimental results show, the problem is solved by the process according to the invention.