Method for application of enamine in palladium catalytic asymmetry allyl group alkylated reaction

An allyl alkylation and asymmetric technology, applied in asymmetric synthesis, organic chemical methods, chemical instruments and methods, etc., can solve the problems of expensive and dangerous reagents, harsh reaction conditions, troublesome operation, etc., and achieve high reaction Active, easy and safe operation, good application effect

Inactive Publication Date: 2008-03-12
SHANGHAI JIAO TONG UNIV
View PDF0 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Its disadvantages are: harsh reaction conditions, expensive and dangerous reagents, troublesome operation

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 application of enamine in palladium catalytic asymmetry allyl group alkylated reaction

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] 1. Preparation of enamine

[0020] Cyclohexanone (20 g, 0.20 mol) was dissolved in cyclohexane (250 mL), then anhydrous magnesium sulfate (120 g) was added in one portion under nitrogen. The system was cooled down to 0° C., and pyrrolidine (84 mL, 1.0 mol, 5 equiv) was added thereto through a syringe for about 0.5 h. Continue to keep warm for 0.5h, and then stir the mixed system at room temperature overnight. Magnesium sulfate was removed by filtration and washed with ring-dried cyclohexane (3 x 50 mL). The combined filtrates were evaporated to remove the solvent under reduced pressure, and the residue was distilled under reduced pressure (69°C / 1mmHg) to obtain the product N-cyclohexenylpyrrolidine as a colorless liquid. Sealed under nitrogen and stored in refrigerator.

[0021] 1 H NMR (CDCl 3 , 400Hz): δ1.49-1.55(m, 2H), 1.62-1.68(m, 2H), 1.78-1.82(m, 4H), 2.05-2.09(m, 2H), 2.14-2.17(m, 2H) , 2.95-2.98(m, 4H), 4.24-4.26(m, 1H).

[0022] 2. Application in asymme...

Embodiment 2

[0025] 1. Preparation of enamine

[0026] Cyclohexanone (20 g, 0.20 mol) was dissolved in cyclohexane (250 mL), then anhydrous magnesium sulfate (120 g) was added in one portion under nitrogen. The system was cooled down to 0° C., and pyrrolidine (84 mL, 1.0 mol, 5 equiv) was added thereto through a syringe for about 0.5 h. Continue to keep warm for 0.5h, and then stir the mixed system at room temperature overnight. Magnesium sulfate was removed by filtration and washed with ring-dried cyclohexane (3 x 50 mL). The combined filtrates were evaporated to remove the solvent under reduced pressure, and the residue was distilled under reduced pressure (69°C / 1mmHg) to obtain the product N-cyclohexenylpyrrolidine as a colorless liquid. Sealed under nitrogen and stored in refrigerator.

[0027] 1 H NMR (CDCl 3 , 400Hz): δ1.49-1.55(m, 2H), 1.62-1.68(m, 2H), 1.78-1.82(m, 4H), 2.05-2.09(m, 2H), 2.14-2.17(m, 2H) , 2.95-2.98(m, 4H), 4.24-4.26(m, 1H).

[0028] 2. Application in asymme...

Embodiment 3

[0031] 1. Preparation of enamine

[0032] Cyclohexanone (20 g, 0.20 mol) was dissolved in cyclohexane (250 mL), then anhydrous magnesium sulfate (120 g) was added in one portion under nitrogen. The system was cooled down to 0° C., and pyrrolidine (84 mL, 1.0 mol, 5 equiv) was added thereto through a syringe for about 0.5 h. Continue to keep warm for 0.5h, and then stir the mixed system at room temperature overnight. Magnesium sulfate was removed by filtration and washed with ring-dried cyclohexane (3 x 50 mL). The combined filtrates were evaporated to remove the solvent under reduced pressure, and the residue was distilled under reduced pressure (69°C / 1mmHg) to obtain the product N-cyclohexenylpyrrolidine as a colorless liquid. Sealed under nitrogen and stored in refrigerator.

[0033] 1 H NMR (CDCl 3 , 400Hz): δ1.49-1.55(m, 2H), 1.62-1.68(m, 2H), 1.78-1.82(m, 4H), 2.05-2.09(m, 2H), 2.14-2.17(m, 2H) , 2.95-2.98(m, 4H), 4.24-4.26(m, 1H).

[0034] 2. Application in asymme...

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 present invention relates to a method in the chemical technological field wherein the enamine is used in the palladium-catalyzed asymmetric allyl alkylation; the chiral ligand and the palladium catalyst are dissolved in the solvent first and react at the room temperature; the substituted allyl acetate is added; the mixture is stirred; then the enamine category compounds are added in the reaction; the cold saturated ammonium chloride solution is used for hydrolysis after the reaction is finished; thus, the product can be made. The enamine is a quite convenient and quite promising pro-nuclear reagent and overcomes the trouble of the unstable enol ether caused by the replacement of the alkali with the simple ketone; the operation is simple and safe; and the catalytic reaction has the high activity and selectivity of the reaction.

Description

technical field [0001] The invention relates to an asymmetric synthesis method in the technical field of chemical industry, in particular to a method for using enamine in a palladium-catalyzed asymmetric allyl alkylation reaction. Background technique [0002] In the current literature, asymmetric allyl substitution reactions using simple ketones as nucleophiles always form unstable enol structures. This just needs the condition of following several aspects: 1) needs to use the very strong base of basicity, such as butyllithium or LDA etc., not only the price of reagent is comparatively expensive, danger is also big; 2) preparation enol formula reactive intermediate The conditions required during this process are very harsh, otherwise it will either cause reaction failure or may cause experimental accidents. Sometimes additives need to be added to make negative ions form relatively stable enol ethers; 3) enol ethers must be prepared and used before each reaction. , making t...

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): C07C49/796C07C45/00C07B53/00
Inventor 张万斌谢芳刘德龙
Owner SHANGHAI JIAO TONG UNIV
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