Platinum-xanthene-bromine complex

Abstract

The invention relates to a platinum-xanthene-bromide complex and use thereof in catalyzing a hydroformylation reaction.

Description

Technical Field

[0001] The present invention relates to a platinum-xanthene-bromine complex and its use in catalyzing hydroformylation reaction. Background Art

[0002] C. Botteghi et al., Journal of Molecular Catalysis A: Chemical 200, (2003), 147-156 describe the use of Pt(4,5-bis(diphenylphosphino)-9,9-dimethylxanthene)Cl2 for the hydroformylation of 2-tosyloxystyrene. Summary of the invention

[0003] The problem to be solved by the present invention is to provide a novel complex which, compared with the Pt(4,5-bis(diphenylphosphino)-9,9-dimethylxanthene)Cl2 complexes described in the prior art, should provide an increased yield in the catalysis of hydroformylation reactions.

[0004] This object is achieved by the complexes described in the present invention.

[0005] The complexes include:

[0006] a) Pt;

[0007] b) a ligand conforming to formula (I):

[0008]

[0009] Where R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 Selected from: -H, -(C1-C 12 )-alkyl, -(C6-C 20 )-aryl;

[0010] And, if R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 Yes-(C6-C 20 )-aryl, the aromatic ring may have a member selected from -(C1-C 12 )-alkyl, -O-(C1-C 12 )-alkyl substituents;

[0011] c) Bromine ligand.

[0012] Terminology (C1-C 12 )-Alkyl includes straight-chain and branched alkyl groups having 1 to 12 carbon atoms. These are preferably (C1-C8)-alkyl, more preferably (C1-C6)-alkyl, most preferably (C1-C4)-alkyl.

[0013] Suitable (C1-C 12 )-alkyl, in particular methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, 2-pentyl, 2-methylbutyl, 3-methylbutyl, 1,2-dimethylpropyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl, n-hexyl, 2-hexyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,1-dimethylbutyl, 1,2- Dimethylbutyl, 2,2-dimethylbutyl, 1,3-dimethylbutyl, 2,3-dimethylbutyl, 3,3-dimethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethylbutyl, 1-ethyl-2-methylpropyl, n-heptyl, 2-heptyl, 3-heptyl, 2-ethylpentyl, 1-propylbutyl, n-octyl, 2-ethylhexyl, 2-propylheptyl, nonyl, decyl.

[0014] Terminology (C6-C 20 )-Aryl includes monocyclic or polycyclic aromatic hydrocarbon groups having 6 to 20 carbon atoms. These are preferably (C6-C 14 )-aryl, more preferably (C6-C 10 )-aryl.

[0015] Suitable (C6-C 20 )-aryl, in particular phenyl, naphthyl, indenyl, fluorenyl, anthracenyl, phenanthrenyl, naphthacene, Preferred (C6-C 20 )-Aryl is phenyl, naphthyl and anthracenyl.

[0016] In one embodiment, R 2 , R 3 , R 5 , R 6 , R 7 , R 8 Selected from: -(C1-C 12 )-alkyl, -(C6-C 20 )-aryl.

[0017] In one embodiment, R 5 , R 6 , R 7 , R 8Yes-(C6-C 20 )-aryl.

[0018] In one embodiment, R 5 , R 6 , R 7 , R 8 Yes - Ph.

[0019] In one embodiment, R 2 and R 3 Yes - (C1-C 12 )-alkyl.

[0020] In one embodiment, R 2 and R 3 It is -CH3.

[0021] In one embodiment, R 1 and R 4 Yes -H.

[0022] In one embodiment, the ligand according to formula (I) has structure (1):

[0023]

[0024] (1): 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene.

[0025] In one embodiment, the complex has exactly one ligand corresponding to formula (I).

[0026] In one embodiment, the complex has at least two bromine ligands.

[0027] In one embodiment, the complex has exactly two bromine ligands.

[0028] In one embodiment, the complex has the following structure: Pt(4,5-bis(diphenylphosphino)-9,9-dimethylxanthene)Br2.

[0029] In addition to the complexes themselves, their use for catalyzing hydroformylation reactions is also claimed.

[0030] The complex is used for catalyzing hydroformylation reaction. DETAILED DESCRIPTION

[0031] The present invention will be described in detail below by means of working examples.

[0032] Experimental Description

[0033] PtX2 (X = halogen), ligand and oven-dried stirring rod are loaded into a vial. The vial is then sealed with a diaphragm (PTFE-coated styrene-butadiene rubber) and a phenolic resin cap. The vial is evacuated and refilled with argon three times. Toluene and olefins are added to the vial using a syringe. The vial is placed in an alloy plate (Legierungsplatte) and transferred to a 4560 series autoclave from Parr Instruments under an argon atmosphere. After purging the autoclave three times with CO / H2, the synthesis gas pressure is increased to 40 bar at room temperature. The reaction is carried out at 120°C for 20h / 18h. After the reaction is completed, the autoclave is cooled to room temperature and carefully decompressed. The yield and selectivity are determined by GC analysis.

[0034] Hydroformylation of 1-octene

[0035]

[0036] Reaction conditions:

[0037] 20 mmol of 1-octene, 1.0 mol% of Pt, 2.2 equivalents of 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (1), solvent: toluene, p(CO / H2): 40 bar, T: 120°C, t: 20 h.

[0038] Yield:

[0039] PtBr2: 99%

[0040] PtCl2: 30%.

[0041] Halogen Variations (2-Octene)

[0042]

[0043] Reaction conditions:

[0044] 20 mmol of 2-octene, 1.0 mol% of Pt, 1.1 equivalents of 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (1), solvent: toluene, p(CO / H2): 40 bar, T: 120°C, t: 20 h.

[0045] Yield:

[0046] PtBr2: 99%

[0047] PtCl2: 16%.

[0048] Halogen Variations (1-Octene)

[0049] Reaction conditions:

[0050] 10.0 mmol of 1-octene, 0.1 mol% PtX2, 2.2 equivalents of ligand, solvent: toluene, p(CO / H2): 40 bar, T: 120°C, t: 20 h.

[0051] Yield:

[0052]

[0053] Changes in ligands and changes in halogens

[0054] Reaction conditions:

[0055] 1.0 mmol of 2-octene, 0.5 mol% PtX2, 2.0 equivalents of ligand, solvent: toluene, p(CO / H2): 40 bar, T: 120°C, t: 18 h.

[0056] Yield:

[0057]

[0058] Changes in equivalence and halogen content

[0059] Reaction conditions:

[0060] 1.0 mmol of 1-octene, 1.0 mol% Pt(acac)2, LiX (X = halogen), 2.2 equivalents of 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (1), solvent: toluene, p(CO / H2): 40 bar, T: 120°C, t: 20 h.

[0061] LiX equivalent X Yield [%] 0.5 Br 68 2.0 Br 71 1.5 Cl 0 4.0 Cl 0。

[0062] As shown by the experimental results, this object is achieved by the complex according to the invention.

Claims

1. A complex comprising: a) Pt; b) a ligand conforming to formula (I): Where R 1 and R 4 Yes - H, R 2 and R 3 Yes - (C1-C 12 )-alkyl, and R 5 , R 6 , R 7 , R 8 Yes-(C6-C 20 )-aryl; c) Bromine ligand.

2. The complex according to claim 1, The ligand conforming to formula (I) has structure (1):

3. The complex according to any one of claims 1 to 2, Therein the complex has exactly one ligand which corresponds to formula (I).

4. The complex according to any one of claims 1 to 2, The complex has at least two bromine ligands.

5. The complex according to any one of claims 1 to 2, Therein the complex has exactly two bromine ligands.

6. The complex according to any one of claims 1 to 2, The complex has the following structure: Pt(4,5-bis(diphenylphosphino)-9,9-dimethylxanthene)Br2.

7. Use of the complex according to any one of claims 1 to 6 for catalyzing hydroformylation reactions.

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