Palladium catalyst, and preparation method and application thereof

A palladium catalyst and selected technology, applied in chemical instruments and methods, organic chemistry, compounds containing elements of Group 8/9/10/18 of the periodic table, etc., can solve the problem of poor catalytic controllability of divalent nickel salt, structural It is not easy to trim and modify, and the synthesis of rhodium complexes is difficult to achieve the effects of easy modification and trimming, narrow molecular weight distribution, and easy synthesis.

Inactive Publication Date: 2013-04-03
HEFEI UNIV OF TECH
View PDF3 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, these catalysts all have their shortcomings, such as the poor controllability of divalent nickel salt catalysis; the structure of Pd-Pt complexes is not easy to cut and modify, the polymerization process is very sensitive to oxygen and water, and metal Pt is expensive; rhodium Complex synthesis is difficult, and a large amount of ligand additives need to be added during the polymerization process

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Palladium catalyst, and preparation method and application thereof
  • Palladium catalyst, and preparation method and application thereof
  • Palladium catalyst, and preparation method and application thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] Embodiment 1: the preparation of methyl substitution palladium catalyst

[0036]a. Using 1.73g (1.5mmol) of tetrakis(triphenylphosphine)palladium and 0.28g (1.5mmol) of copper iodide as catalysts, take 3.15g (32.1mmol) of trimethylsilylacetylene and 5.00g of 4-bromotoluene g (29.2mmol) was dissolved in dry 70mL triethylamine, reacted at 55°C in a nitrogen atmosphere for 20h, added 15mL water to quench the reaction, extracted the organic phase with 100mL ethyl acetate, followed by saturated ammonium chloride solution , saturated sodium bicarbonate solution, and saturated sodium chloride solution, washed 3 times, added anhydrous sodium sulfate to dry, and evaporated to remove the solvent to obtain a crude product. The crude product was subjected to silica gel column chromatography (eluent by volume ratio: petroleum ether: ethyl acetate ester = 4:1), purified and dried in vacuo to obtain a yellow oily liquid which is Intermediate I. The structural formula is as follows:

...

Embodiment 2

[0047] Embodiment 2: Initiate benzene isonitrile polymerization reaction

[0048] The polymerization of benzyl isonitrile is carried out under anhydrous and oxygen-free conditions. Add 2.5 μmol (1.3 mg) of the palladium catalyst prepared in Example 1 and 0.12 mmol (44.9 mg) of benzyl isonitrile monomer into a 10 mL polymerization bottle, vacuumize and fill with nitrogen to repeat 3 times, add 0.6mL of dry tetrahydrofuran, reflux at 55°C for 20h, add 10mL of methanol to quench, and precipitate the polymer, wash 5 times with methanol, centrifuge to obtain a yellow flocculent precipitate, and vacuum-dry until the mass is low. Change. Obtain 36.6mg polyisocyanide, its number-average molecular weight is 1.52×10 4 , the molecular weight distribution index is 1.19.

[0049] The structural formula of the benzene isonitrile monomer in the present embodiment is:

[0050]

Embodiment 3

[0051] Embodiment 3: Initiate benzene isonitrile polymerization reaction

[0052] The polymerization of benzene isonitrile is carried out under anhydrous and oxygen-free conditions. Add 2.1 μmol (1.1 mg) of palladium catalyst prepared in Example 1 and 0.15 mmol (41.6 mg) of benzene isonitrile monomer into a 10 mL polymerization bottle, vacuumize and fill with nitrogen to repeat 3 times, add 0.7 mL of dry tetrahydrofuran, reflux reaction at 55°C for 20 h, add 10 mL of methanol to quench, and precipitate the polymer, wash with methanol for 5 times, centrifuge to obtain yellow flocculent precipitate, and vacuum-dry until the mass is low. Change. Obtain 36.3mg polyisocyanide, its number average molecular weight is 2.06×10 4 , The molecular weight distribution index is 1.22.

[0053] The structural formula of the benzene isonitrile monomer in the present embodiment is:

[0054]

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a palladium catalyst, and a preparation method and application thereof. The structure of the palladium catalyst is represented by the following general formula, wherein R is selected from -CH2CH3 and -Ph, and R1 is selected from -CH3, -CF3, -H, -F, -NO2, -OCH3 and -COOCH3. The palladium catalyst disclosed by the invention has favorable isonitrile polymerization catalyzing power, is easy to synthesize, has high stability, and can be used for active / controllable polymerization of isonitrile monomers; and the obtained polyisonitrile has high molecular weight and narrow molecular weight distribution.

Description

1. Technical field [0001] The invention relates to a palladium catalyst and a preparation method thereof, in particular to a catalyst for initiating isonitrile polymerization and a preparation method thereof. It belongs to the field of polymer catalysis. 2. Background technology [0002] Polyisocyanide is the first reported polymer with a stable helical conformation, which has important research significance and application prospects in the fields of chiral molecular recognition, asymmetric catalysis, and enantiomer separation. The most commonly used catalysts for isonitrile polymerization today are transition metal complexes such as Ni(II), Pd(II)-Pt(II) or Rh(III) complexes. Ni(II) is the earliest standard catalyst found for isonitrile polymerization, mainly NiCl 2 ·6H 2 O, Ni(ClO 4 ) 2 ·6H 2 O, Ni(acac) 2 and other forms, where NiCl 2 ·6H 2 O, Ni(ClO 4 ) 2 ·6H 2 O is effective for the living polymerization of aliphatic isonitriles, while Ni(acac) 2 It is an e...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C08G73/00C07F15/00
Inventor 吴宗铨薛雅欣刘娜贺晓悦高龙美田发银
Owner HEFEI UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products