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Recovery preparation method of D-(+)-di-p-toluoyl tartaric acid

A technology of toluoyl tartaric acid and toluoyl tartrate is applied in the field of recovery and preparation of D--di-p-toluoyl tartaric acid, and can solve the problems of difficult toluoyl tartaric acid curing, high production cost, high environmental protection pressure and the like

Pending Publication Date: 2021-02-12
SHANDONG XINHUA PHARMA CO LTD
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Due to problems such as esterification, ester hydrolysis, and transesterification in the recovery and preparation process of D-(+)-di-p-toluoyl tartaric acid, and the conversion of D-(+)-di-p-toluoyl tartaric acid into hydrochloride, D -(+)-Di-p-toluoyl tartaric acid is difficult to solidify and other problems. The current production process generally treats the mother liquor containing D-(+)-di-p-toluoyl tartaric acid as waste liquid, resulting in high production costs and environmental protection pressure. question

Method used

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Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0015] Example 1: Examples of sources of D-(+)-di-p-toluoyl tartrate crude product mother liquor and D-(+)-di-p-toluoyl tartrate fine-quality mother liquor (see CN103342664B, Zhai Jisheng, etc.)

[0016] Add 20.0kg diol hydrobromide, 80L dichloromethane, 10kg30% sodium hydroxide, and 20L water to the reaction tank, and stir to react. Let stand, separate the water layer, wash the organic layer with water, and distill dichloromethane to obtain diol oil.

[0017] Add 80L of isopropanol, 0.2kg of water, stir, add 9.5kg of D-(+)-di-p-toluoyl tartaric acid at 40°C, stir and crystallize. Cool down, centrifuge, wash with isopropanol, and dry to obtain 12.4 kg of crude D-(+)-di-p-toluoyl tartrate, with a content of 92% and a yield of 90.1%. The centrifuged mother liquor is the crude product mother liquor of D-(+)-di-p-toluoyl tartrate.

[0018] Add 12.4kg of crude D-(+)-di-p-toluoyl tartrate and 9L of methanol to the reaction tank, quickly heat up to 40°C to dissolve, add 36L of isop...

Embodiment 2

[0019] Embodiment 2: the recovery preparation of D-(+)-di-p-toluoyl tartaric acid (1)

[0020] ①Evaporation of solvent: add D-(+)-di-p-toluoyl tartrate crude product mother liquor and D-(+)-di-p-toluoyl tartrate fine mother liquor each 1 batch, totaling 140L, into the reaction tank, and evaporate the solvent under reduced pressure Isopropanol, methanol, D-(+)-di-p-toluoyl tartrate oil. The highest temperature is 58°C.

[0021] ②Transformation: Add hydrochloric acid dropwise to the oil under vigorous stirring at room temperature, and control the time for 4 hours until pH=2. Stirring was continued for 2 h to control pH=3, D-(+)-di-p-toluoyl tartrate was converted into hydrochloride and D-(+)-di-p-toluoyl tartaric acid was generated.

[0022] ③ Centrifugation: Centrifuge, wash with water, and dry to obtain 9.3kg of D-(+)-di-p-toluoyl tartaric acid powder. Samples were taken to detect the melting point of 168-169°C and the specific rotation of +137°.

Embodiment 3

[0023] Embodiment 3: the recovery preparation of D-(+)-di-p-toluoyl tartaric acid (2)

[0024] ① Evaporation of solvent: add 1 batch of D-(+)-di-p-toluoyl tartrate crude product mother liquor and D-(+)-di-p-toluoyl tartrate fine mother liquor, a total of 143L, into the reaction tank, and evaporate the solvent under reduced pressure Isopropanol, methanol, D-(+)-di-p-toluoyl tartrate oil. The maximum temperature is 60°C.

[0025] ② Transformation: Add hydrobromic acid dropwise to the oil under vigorous stirring at room temperature, and control the time for 6 hours until pH=3. Stirring was continued for 2h to control pH=3, D-(+)-di-p-toluoyl tartrate was converted into hydrobromide and D-(+)-di-p-toluoyl tartaric acid was generated.

[0026] ③ Centrifugation: Centrifuge, wash with water, and dry to obtain 9.2 kg of D-(+)-di-p-toluoyl tartaric acid powder. Samples were taken to detect the melting point of 169-170°C and the specific rotation of +139°.

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Abstract

The invention provides a recovery and preparation method of D-(+)-di-p-toluoyl tartaric acid. The method comprises the following steps: (1) evaporating a solvent: adding D-(+)-di-p-toluoyl tartrate crude mother liquor and D-(+)-di-p-toluoyl tartrate fine mother liquor into a reaction tank, and evaporating under reduced pressure to remove solvents isopropanol and methanol to obtain a D-(+)-di-p-toluoyl tartrate oily matter or solid matter; (2) conversion: dropwise adding inorganic acid into the D-(+)-di-p-toluoyl tartrate oily matter or solid matter at room temperature under stirring, and controlling the pH value; and (3) centrifuging: centrifuging, washing and drying to obtain D-(+)-di-p-toluoyl tartaric acid. The method is high in operability and simple in process, and the product qualitymeets the production requirement.

Description

technical field [0001] The invention belongs to the field of drug synthesis, in particular to a method for recovering and preparing D-(+)-di-p-toluoyl tartaric acid in the production of escitalopram oxalate. Background technique [0002] Citalopram is clinically used for the treatment of depression, and D-(+)-di-p-toluoyl tartaric acid is used as a resolution agent in its synthesis process. [0003] Due to problems such as esterification, ester hydrolysis, and transesterification in the recovery and preparation process of D-(+)-di-p-toluoyl tartaric acid, and the conversion of D-(+)-di-p-toluoyl tartaric acid into hydrochloride, D -(+)-Di-p-toluoyl tartaric acid is difficult to solidify and other problems. The current production process generally treats the mother liquor containing D-(+)-di-p-toluoyl tartaric acid as waste liquid, resulting in high production costs and environmental protection pressure. question. Contents of the invention [0004] The invention provides ...

Claims

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Application Information

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IPC IPC(8): C07C67/54C07C67/28C07C67/48C07C69/78
CPCC07C67/54C07C67/28C07C67/48C07B2200/07C07C69/78
Inventor 翟吉胜赵春燕窦国华郭统山于磊
Owner SHANDONG XINHUA PHARMA CO LTD
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