Preparation method of C-14 enol ether

A C-14, enol ether technology, applied in ether preparation, organic chemistry and other directions, can solve the problems of difficult synthesis, pollution, difficulty in the source of raw material C-4 phosphonates, etc.

Inactive Publication Date: 2011-09-14
SHAOXING UNIVERSITY
View PDF2 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0023] Among the above-mentioned three methods, A method needs a large excess of methyl chloroacetate and alkali; B. method will use expensive methyl iodide, polluted dimethyl sulfide and dangerous strong base DMSO sodium salt; method C is the latest The route has great potential for industrialization, but the source of the raw material C-4 phosphonate (6) is difficult, the synthesis is difficult, and it is difficult to apply to industrial production

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
  • Preparation method of C-14 enol ether
  • Preparation method of C-14 enol ether
  • Preparation method of C-14 enol ether

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0045] Example 1: Preparation of diethyl methoxymethylphosphonate (8).

[0046]In a 1000mL four-neck flask equipped with mechanical stirring, add 455g of triethyl phosphonite, start stirring and heat to 60°C-70°C, and add 80.5g of chloromethyl methyl ether dropwise within 1h. GC tracking, the reaction was completed in about 2 hours. Cool down, recover the solvent, distill the residue under reduced pressure, collect 165g of 102-103°C / 9mmHg fraction, it is a colorless transparent liquid, the gas phase content is 98.5%, and the yield is 89.2%.

[0047] .

[0048] 1 HNMR (δ, ppm, 400MHz , CDCl 3 ): 1.36(t, 6H, CH 2 CH 3 ); 3.48(s, 3H, CH3); 3.74(d, 2H, -CH2-); 4.15-4.22(m, 4H, CH 2 CH 3 ).

[0049] 13 CNMR (400MHz, CDCl 3 )δ (ppm): 16.45, 16.51, 61.30, 61.43, 62.44, 65.93, 67.58.

Embodiment 2

[0050] Example 2:: Preparation of C-14 Enol Ether (7).

[0051] In a nitrogen-protected 250mL three-neck flask, add 12.3g of potassium tert-butoxide (0.11mol) and 50mL of a 8:1 (v / v) mixture of tetrahydrofuran and dimethyl sulfoxide, keep warm in a cold bath, and under mechanical stirring, drop Add 18.2g diethyl methoxymethylphosphonate (8) (0.1 mole), keep at -30~-25°C for about half an hour to complete the dropwise addition, continue to keep warm and stir for about 1 hour to make the carbanion dissociation reaction fully, and then keep Add 19.2g of β-ionone (4) (0.1mol) dropwise at -30~-25℃, and the dropwise addition is completed in about 1 hour. Continue to keep warm and stir for about half an hour. After the reaction is completed by gas chromatography, add 50mL of water and 100mL of ether and stir for 10min. Layered, the ether layer was washed 3 times with 5% aqueous sodium chloride solution (25 mL each time), the organic layer was dried over magnesium sulfate and filtered...

Embodiment 3-9

[0058] Example 3-9: Preparation of C-14 Enol Ether (7) by Condensation Reaction under Different Bases, Solvents and Temperature Conditions.

[0059] In a 250mL three-neck bottle protected by nitrogen, add a certain amount of alkali and 20mL of a certain solvent (see the table below for the types of alkali and solvent), keep warm in a cold bath, and add a certain amount of diethyl methoxymethylphosphonate dropwise under mechanical stirring. (8) 20mL of a certain solvent (see the table below for the molar quantity) (same as the above solvent), keep a certain temperature for about half an hour to complete the dropwise addition, continue to keep warm and stir for about 1 hour to make the carbanion dissociation reaction fully, and then keep the above temperature Add 9.6g of β-ionone (4) (0.05mol) into the solvent (same as the above solvent) dropwise, and the dropwise addition is completed in about 1 hour, continue to keep warm and stir for about half an hour, after the reaction is c...

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 relates to a preparation method of C-14 enol ether. The C-14 enol ether is an intermediate of vitamin A, and the chemical name of the C-14 enol ether is 1-methoxy-2-methyl-4-(2,6,6-trimehtyl-1-cyclohexene-1-ly)-1,3-butadiene. The preparation method comprises the step of carrying out Wittig-Horner condensation reaction on beta-irisone as shown in a formula 4 and diethyl methylphosphonate as shown in a formula 8 at the temperature of minus 40-30 DEG C in an ether solvent or dipolar aprotic solvent in the presence of alkali so as to prepare the C-14 enol ether as shown in a formula7. According to the preparation method, reaction route is simple, and raw materials are simple and available.

Description

Technical field: [0001] The present invention relates to a preparation method of vitamin A intermediate C-14 enol ether, the chemical name of C-14 enol ether is 1-methoxy-2-methyl-4-(2,6,6-tri Methyl-1-cyclohexen-1-yl)-1,3-butadiene, the chemical formula is shown in formula 7. [0002] [0003] Formula 7. Background technique: [0004] Vitamin A and its derivatives are an important class of medicines, which are used to treat night blindness, dry eyes, corneal softening, and dry skin; they can promote human growth and development, and can enhance resistance to diseases; at the same time, vitamin A It is also an important feed additive. 2-Methyl-4-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2-buten-1-aldehyde (C-14 aldehyde) is a key intermediate in the synthesis of vitamin A For example, in 1947, in the C14+C6 route developed by O.Isler et al. of Roche, Switzerland, starting from C-14 aldehyde, it was prepared by Grignard reaction, hydrogenation, acetylation, hydroxyl brominati...

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): C07C43/162C07C41/01
Inventor 吴春雷高晓忠邓莉平周玉波吴永华谢海燕
Owner SHAOXING UNIVERSITY
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