Method for preparing 2-benzyl pyridine compound

A technology for benzylpyridine and compounds, applied in the field of preparing 2-benzylpyridine compounds, which can solve the problems of high molecular weight, poor atom economy, and low yield of synthetic reagents

Inactive Publication Date: 2010-10-20
UNIV OF SCI & TECH OF CHINA
View PDF2 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The limitations of this method are: the molecular weight of the synthetic reagent used is large, and the atom economy is not good; it is necessary to use 1.2 times the equivalent of relatively expensive cesium carbonate as a base; the compatibility of functional groups is not good enough, etc.
2. Traditional synthesis method: using the method of condensation of benzyl chloride and pyridine hydrochloride to synthesize, the disadvantage is that the yield is very low, only about 50%

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
  • Method for preparing 2-benzyl pyridine compound
  • Method for preparing 2-benzyl pyridine compound
  • Method for preparing 2-benzyl pyridine compound

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0066] Embodiment 1, preparation p-chloro 2-benzylpyridine:

[0067] Reaction formula:

[0068]

[0069] The specific method is as follows: in the vacuum reactor, add 1.2 millimoles of 2-pyridine acetic acid potassium salt, and the molar dosage is 0.005 millimoles of three (dibenzylidene acetone) dipalladium catalysts and electrophilic substrate molar dosage 0.5%. 0.015 millimoles of Xant-Phos phosphine ligand with a molar dosage of 1.5%, vacuumize, pass high-purity argon, replace three times, and add 1 millimole of electrophilic substrate p-chlorobromobenzene and solvent under the protection of argon flow Diethylene glycol dimethyl ether (the amount of solvent is added according to 0.2 milliliters of solvent per millimole of electrophilic substrate), placed at 150 ° C, heated and stirred for 24 hours, according to the following method for the reaction system after the completion of the decarboxylation coupling reaction Purification treatment to obtain the target product p...

Embodiment 2

[0071] Embodiment 2, preparation 4-methoxyphenyl-2-pyridyl methane:

[0072] Reaction formula:

[0073]

[0074] The specific method is as follows: in the vacuum reactor, add 1.2 millimoles of 2-pyridine acetic acid potassium salt, 1 millimole of electrophilic substrate p-methoxy bromobenzene, and the molar dosage is 0.5% tris( Dibenzylidene acetone) Dipalladium catalyst 0.005 millimoles and molar dosage are 0.015 millimoles of Xant-Phos phosphine ligand of electrophilic substrate molar dosage 1.5%, vacuumize, logical high-purity argon, displacement three times, in argon flow Add the solvent 1,3,5-trimethylbenzene (mesitylene) under the protection of protection (the amount of solvent is added according to 0.2 ml per millimole of the electrophilic substrate), place it at 150 ° C, heat and stir for 24 hours, and the reaction system after the reaction is completed The mixture was filtered, and the reaction solution was directly chromatographed by fast silica gel column chroma...

Embodiment 3

[0076] Embodiment 3, preparation 2-pyridyl-3-pyridyl methane:

[0077] Reaction formula:

[0078]

[0079] The specific method is as follows: add 1.2 millimoles of 2-pyridine acetic acid potassium salt in the vacuum reactor, and the molar dosage is 0.005 millimoles and molar dosage of tris(dibenzylideneacetone) dipalladium catalyst of 0.5% electrophilic substrate molar dosage 0.015 millimoles of Xant-Phos phosphine ligand with an amount of 1.5% for the electrophilic substrate, vacuumize, pass high-purity argon, replace three times, and add 1 millimole of the electrophilic substrate 3-bromo under the protection of the argon flow Pyridine and the solvent diethylene glycol dimethyl ether (the amount of solvent is added according to 0.2 milliliters of solvent per millimole of electrophilic substrate), placed at 150 ° C, heated and stirred for 24 hours, according to the following method for the completion of the decarboxylation coupling reaction The reaction system is purified ...

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 method for preparing 2-benzyl pyridine compounds, which comprises the following step of performing a decarboxylation coupling reaction of a decarboxylation coupling reagent and an electrophilic substrate in an organic solvent in the presence of a palladium catalyst and phosphine ligand to obtain 2-benzyl pyridine compounds. Through the method, the aim of synthesizing an important intermediate, which is functionalized 2-benzyl pyridine, and derivatives thereof in the organic synthesis or the synthesis of medicinal intermediates is realized, and the method provides an effective solution for the synthesis of the compounds in the organic synthetic chemistry and the synthesis of the medicinal intermediates. The method has the advantages of avoidance of dependency on alkali, low cost, safety, stability, low toxicity, convenient operation, a few by-products, atomic economy higher than that of the prior art, green chemistry properties, little catalytic amount, high catalytic efficiency, easy separation and high conversion rate and yield, and has industrial and synthetic values.

Description

technical field [0001] The invention relates to a method for preparing 2-benzylpyridine compounds. Background technique [0002] At present, the main methods of the reported synthetic functionalized 2-benzylpyridine compounds are: 1. Palladium-Catalyzed 2-Pyridylmethyl Transfer from 2-(2-Pyridyl)-ethanol Derivatives toOrganic Halides by Chelation-Assisted Cleavage of Unstrained Csp3-Csp3 Bonds and the method presented in Takashi Niwa, Hideki Yorimitsu, and Koichiro Oshima, Angew.Chem.Int.Ed., 2007, 46, 2643-2645, using diisopropylpyridyl alcohol as a synthetic reagent, catalyzed by palladium system, and using cesium carbonate as the base, the synthesis of p-benzylpyridine compounds was realized. The limitations of this method are: the molecular weight of the synthetic reagent used is large, and the atom economy is not good; 1.2 times the equivalent of relatively expensive cesium carbonate needs to be used as a base; the compatibility of functional groups is not good enough,...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C07D213/26C07D213/30C07D213/06C07D213/127C07D213/48C07D213/55C07D213/57C07D405/10C07D213/16C07D409/06C07D213/32
Inventor 尚睿徐清傅尧郭庆祥刘磊
Owner UNIV OF SCI & TECH OF CHINA
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap