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Process for preparing (r)-aryloxypropionic acid ester derivatives

A technology of aryloxy propionate and derivatives, which is applied in the field of preparing (R) aryloxy propionate derivatives, and can solve problems such as increasing cost

Inactive Publication Date: 2005-08-31
KOREA RES INST OF CHEM TECH
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

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Problems solved by technology

[0013] However, these methods produce about 5-20% by-product (S)-isomers which are difficult to be removed, so that rather complicated processes such as recrystallization are required in order to obtain pure (R)fenoxaprop ethyl, thus increasing the production the cost of
In addition, the starting material (R)-alkyl 2-(4-hydroxyphenoxy)propionate used in the reaction must maintain high optical activity, which is also a burden

Method used

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  • Process for preparing (r)-aryloxypropionic acid ester derivatives
  • Process for preparing (r)-aryloxypropionic acid ester derivatives
  • Process for preparing (r)-aryloxypropionic acid ester derivatives

Examples

Experimental program
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Effect test

Embodiment 1

[0028] Preparation of (D+)-ethyl-2-(4-chloro-2-methylphenoxy)propionate (Compound 1)

[0029] With 30ml cyclohexane, 1.43g (10mmol) 4-chloro-2-methylphenol, 2.86g (10.5mmol) (S)-ethyl O-p-toluenesulfonyl lactate and 2.76g (20mmol) K 2 CO 3 The powder was placed in a 50ml flask equipped with a Dean-Stock cooling condenser and refluxed for 17 hours. Without cooling, the reaction mixture was filtered and the solid filter cake was washed with 20 mL of warm cyclohexane. The cyclohexane layer, that is, the filtrate was concentrated to obtain 2.26 g of the target compound (yield = 93%; purity = 98%, optical purity = 99.4%).

[0030] Rf=0.68(EA:Hx=1:4); 1H NMR (CDCl3, 200MHz) δ1.24(t, J=7.2Hz, 3H), 1.62(d, J=6.8Hz, 3H), 2.25(s, 3H), 4.20(q, J=7.2Hz, 2H), 4.69(q, J=6.8Hz, 1H), 6.58~7.13(m, 3H); MS(70eV) m / z 244(M+), 242( M+), 169, 142, 125, 107, 89, 77

[0031] The following Table 1 shows the yield of compound (1-25), the ratio of the formed optical isomers and the spectral data o...

Embodiment 2

[0039] Preparation of (D+)-ethyl-2-[4-(6-chloro-2-benzoxazolyloxy)-phenoxy]-propionate (compound 26, trade name: Fenoxaprop-p-ethyl)

[0040] With 50ml cyclohexane, 2.61g (10mmol) (6-chloro-2-benzoxazolyl oxygen) phenol, 2.86g (10.5mmol) (S)-ethyl O-p-toluenesulfonyl lactate and 2.76 g(20mmol)K 2 CO 3 The powder was placed in a 100ml flask equipped with a Dean-Stock cooling condenser and refluxed for 12 hours. Without cooling, the reaction mixture was filtered and the solid filter cake was washed with 20 mL of warm cyclohexane. The cyclohexane layer, that is, the filtrate was concentrated to obtain 3.20 g of the target compound (yield = 89%; purity = 98%, optical purity = 99.9%).

[0041]Melting point 82~84 ℃ (observation value); Rf=0.52 (hexane / ethyl acetate=3 / 1); 1H-NMR (CDCl3, 200MHz) δ1.13 (t, J=7.1Hz, 3H), 1.81 ( d, J=6.9Hz, 3H), 4.22(q, J=7.1Hz, 2H), 4.72(q, J=6.9Hz, 1H), 6.99-7.42(m, 7H); MS(70eV) m / z 363(M+), 361(M+), 291, 288, 263, 261, 182, 144, 119, 91.

[004...

Embodiment 3

[0046] Preparation of (D+)-methyl-2-[4-(6-chloro-2-benzoxazolyloxy)-phenoxy]-propionate (compound 27)

[0047] 50ml cyclohexane, 2.61g (10mmol) (6-chloro-2-benzoxazolyl oxygen) phenol, 2.35g (10.5mmol) (S)-methyl O-(p-methoxybenzene)sulfonyl Lactate and 2.12g (20mmol) Na 2 CO 3 The powder was placed in a 100ml flask equipped with a Dean-Stock cooling condenser and refluxed for 12 hours. Without cooling, the reaction mixture was filtered and the solid filter cake was washed with 20 mL of warm cyclohexane. The cyclohexane layer, that is, the filtrate was concentrated to obtain 3.10 g of the target compound (yield = 89%; purity = 98%, optical purity = 99.9%).

[0048] Melting point 97°C (observed value); Rf=0.50 (hexane / ethyl acetate=3 / 1); 1H-NMR (CDCl3, 200MHz) δ1.51 (d, J=6.4Hz, 3H), 3.70(s, 3H), 4.55(q, J=6.4Hz, 1H), 6.84-7.40(m, 7H); MS(70eV) m / z 349(M+), 347(M+), 291, 288, 263, 261, 182 , 144, 119, 91.

[0049] The following Table 3 shows the yield of the substitution ...

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Abstract

The present invention relates to a method for preparing optically active (R)-aryloxypropionic acid ester derivatives, and more particularly to a method for preparing (R)- aryloxypropionic acid ester derivatives with high optical purity and good yield at low cost from phenol derivatives with various substituted functional groups and (S)-alkyl O-arylsulfonyl lactates.

Description

technical field [0001] The present invention relates to a method for preparing optically active (R)-aryloxypropionate derivatives, and more particularly relates to the preparation of (R)-aryloxypropionate represented by the following formula 1 with high optical purity and good yield at low cost The method of propionate derivatives, the method uses phenol derivatives and (S)-alkyl O-aryl sulfonyl lactylates with different substituted functional groups as reactants, in the presence of suitable solvents and bases, in The most suitable temperature for nucleophilic reactions: [0002] [0003] where R 1 is C 1-6 Alkyl or benzyl; A is selected from phenyl, naphthyl, quinoxazolyloxyphenyl (quinoxazolyoxyphenly), benzoxazolyloxyphenyl, benzothiazolyloxyphenyl, phenoxybenzene Aryl groups, pyridyloxyphenyl and phenoxynaphthyl aryl groups, wherein the aryl groups can be replaced by 1-3 members selected from hydrogen atoms, halogen atoms, nitro groups, nitrile groups, acetoxy groups...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): C07B53/00C07C67/31C07C69/712C07C253/30C07C255/55C07D213/64C07D213/643C07D241/44C07D263/58
CPCC07B2200/07C07C253/30C07C67/31C07D213/643C07D241/44C07D263/58C07C69/712C07C255/55
Inventor 金大璜郑谨会张海成高荣宽柳在旭禹在春丘桐完
Owner KOREA RES INST OF CHEM TECH