Method for producing optically active 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl] ethane

一种三氟甲基、光学活性的技术,应用在1-溴-1-[3,5-双(三氟甲基)苯基]乙烷的制备领域,能够解决无法稳定地供给光学活性体、反应性高等问题

Inactive Publication Date: 2013-03-20
KOWA CO LTD
View PDF5 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the high reactivity of 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane, it is difficult for the method of optically resolving the racemic form to supply an optically active form. With the possibility of decomposition and racemization of the target substance, it is estimated that the optically active substance cannot be supplied stably

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 producing optically active 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl] ethane
  • Method for producing optically active 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl] ethane
  • Method for producing optically active 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl] ethane

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0043] The method of the present invention is a preparation method of optically active 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane, which is characterized in that it comprises the following steps: using a) phosphorus halide and hydrogen bromide The combination of b) 1,2-dibromo-1,1,2,2-tetrachloroethane and the general formula (I): P(R 1 )(R 2 )(R 3 ) (where, R 1 , R 2 , and R 3 independently represent C 6-10 Aryl, C 6-10 Aryloxy, C 1-10 Alkyl, C 1-10 Alkoxy, C 3-6 Cycloalkyl, or C 3-6 Cycloalkoxy) a combination of organophosphorus compounds, or c) any one of the combinations of N-bromosuccinimide and dialkyl sulfide as a brominating agent for brominating optically active 1-[3 ,5-bis(trifluoromethyl)phenyl]ethanol. In the case of using a combination of (b) or (c) above as a brominating agent, it is preferable to carry out the reaction in the presence of a solvent.

[0044] The optically active 1-[3,5-bis(trifluoromethyl)phenyl]ethanol used as a raw material in...

Embodiment

[0066] Hereinafter, the present invention will be described in more detail through examples, but the scope of the present invention is not limited by these examples.

[0067] The absolute configuration of 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane shown in Example 1 below is converted to Commercially available α-[3,5-bis(trifluoromethyl)phenyl]ethanamine whose absolute configuration is known was determined by comparing the signs of the specific rotation. In addition, the desired optical purity of 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane was analyzed by chiral HPLC (CHIRALPAK (registered trademark) AS-RH; mobile phase: ethanol / Water = 60 / 40; flow rate: 0.5mL / min; column temperature: 25°C; detection wavelength: 220nm; retention time: first peak / (R) 21.8min, second peak / (S) 26.0min).

[0068] As (S)-1-[3,5-bis(trifluoromethyl)phenyl]ethanol, (S)-1-[3,5-bis(trifluoromethyl)phenyl]ethanol with an optical purity of 99.5% and 98% was used ) phenyl] ethanol, for the p...

example 1-1

[0070] Under argon atmosphere, drop in (S)-1-[3,5-bis(trifluoromethyl)phenyl]ethanol (1.0g, 3.87mmol, >99.5%ee) on a water bath below 20°C Add phosphorus tribromide (0.52g, 1.94mmol), and stir at 19-22°C for 30 minutes. The reaction solution was cooled, hydrogen bromide (30% acetic acid solution) (0.76 mL, 3.87 mmol) was added dropwise below 0°C, and stirred at 13-15°C for 18 hours. The reaction solution was poured into ice water, and extracted with n-hexane (15 mL×2). The combined organic layers were washed with saturated aqueous sodium bicarbonate solution (15 mL×1), followed by saturated brine (15 mL×1), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The obtained crude product was purified by column chromatography (silica gel 8 g, eluent: n-hexane) to obtain 1.06 g of (R)-1-bromo-1-[3,5-bis(trifluoro Methyl)phenyl]ethane.

[0071] Yield: 85%

[0072] Chiral HPLC analysis: optical purity 96.8%ee (first peak), conversion rate 97.3%

[0073]...

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

PropertyMeasurementUnit
chiral purityaaaaaaaaaa
chiral purityaaaaaaaaaa
chiral purityaaaaaaaaaa
Login to view more

Abstract

Disclosed is a method that is for producing 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl] ethane having high optical purity, and that is a method containing a step for brominating optically active 1-[3,5-bis(trifluoromethyl)phenyl] ethanol using, as a brominating agent, either a) the combination of a phosphorus halide and hydrogen bromide, b) the combination of 1,2-dibromo-1,1,2,2-tetrachloroethane and the organophosphorus compound represented by general formula I, which is P(R1)(R2)(R3) (in the formula: R1, R2 and R3 each independently indicate a C6-10 aryl group, a C6-10 aryloxy group, a C1-10 alkyl group, a C1-10 alkoxyl group, a C3-6 cycloalkyl group, or a C3-6 cycloalkoxyl group), or c) the combination of N-bromosuccinimide and a dialkyl sulphide.

Description

technical field [0001] The present invention relates to a method for producing optically active 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane useful as raw materials for the production of medicines, agricultural chemicals and industrial products. Background technique [0002] The optically active 1-[3,5-bis(trifluoromethyl)phenyl]ethyl group is important as a constituent unit of compounds useful for medicines and agricultural chemicals, and as a raw material for the production of compounds containing this group,1 -Bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane is an extremely useful compound. For example, it is disclosed that 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane is used as a raw material in order to prepare a compound that acts as an NK-1 receptor antagonist (Non-Patent Document 1 and 2). However, despite such important uses, for 1-bromo-1-[3,5-bis(trifluoromethyl)phenyl]ethane only the preparation of the racemate is known, and for the optically active compo...

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): C07C17/16C07C22/08C07B53/00
CPCC07C22/08C07C17/16C07B2200/07C07B53/00C07C17/04
Inventor 日下部太一松田健之介山崎浩市扇谷忠明涉谷公幸
Owner KOWA CO LTD
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