Method for preparing chiral amino acid tetrazole compound

Abstract

The invention discloses a method for preparing a chiral amino acid tetrazole compound. The method is characterized by synthesizing and preparing the chiral amino acid tetrazole compound by taking cyanophenylalanine and sodium azide as raw materials, dimethyl formamide as a solvent and imidazole polymer ferric salt ionic liquid as a catalyst, and specifically comprises the following steps: mixing the cyanophenylalanine, the sodium azide, the imidazole polymer ferric salt ionic liquid and the dimethyl formamide which are in proportional amounts, heating to 110 to 130 DEG C while stirring, reacting for 20 to 30 hours at a constant temperature, cooling to room temperature, filtering and separating an imidazole polymer ferric salt ionic liquid catalyst, regulating pH (Potential of Hydrogen) ofa separating solution to be neutral with hydrochloric acid, adding an ethyl acetate for extracting and separating liquid, taking a supernatant organic phase, rotationally drying an organic solvent after washing, obtaining white solid, and carrying out vacuum drying, thus obtaining the chiral amino acid tetrazole compound.

Description

technical field

[0001] The invention relates to a method for preparing chiral amino acid tetrazole compounds, belonging to the technical field of chemical intermediate synthesis. Background technique

[0002] Tetrazolium is a class of nitrogen-containing heterocyclic substances with a wide range of uses, and has important applications in medicine, pesticides and material science. Chiral amino acid derivatives have broad application prospects in disease treatment, photoluminescence, asymmetric catalysis, etc. The traditional synthesis method mainly uses nitrile and sodium azide as raw materials, and is synthesized under Lewis acid catalysis, but the yield Not high, especially the preparation of chiral amino acid tetrazole compounds will be racemized. Contents of the invention

[0003] Purpose of the invention: the technical problem to be solved by this invention is to provide a method for preparing chiral amino acid tetrazole compounds for the deficiencies in the prior art...

Examples

Embodiment 1

[0034] Preparation of imidazole polymer iron salt ionic liquid

[0035] Add vinylimidazole (5mmol) into a three-necked flask, then add chlorobutane (5mmol), and stir at 40°C for 12h to obtain 1-vinyl-3-n-butynylimidazolium chloride.

[0036] Weigh 0.94g of 1-vinyl-3-n-butyrylimidazolium chloride (5mmol) and dissolve it in 5mL of methanol, add 0.05g of dibenzoyl peroxide, stir at 60°C for 15h, cool down to 50°C, add 0.85g anhydrous FeCl 3 (5 mmol), stirred at 50° C. for 0.5 h, and spin-dried the organic solvent to obtain a yellow solid, which was vacuum-dried at 50° C. to obtain an imidazole polymer iron salt ionic liquid.

Embodiment 2

[0038] Preparation of imidazole polymer iron salt ionic liquid

[0039] Add vinylimidazole (5mmol) into a three-necked flask, then add chlorobutane (15mmol), and stir at 80°C for 5h to obtain 1-vinyl-3-n-butynylimidazolium chloride.

[0040] Weigh 0.94g of 1-vinyl-3-n-butyrylimidazolium chloride (5mmol) and dissolve it in 45mL of methanol, add 0.01g of dibenzoyl peroxide, stir at 90°C for 6h, cool down to 30°C, add 0.42g anhydrous FeCl 3 (2.5 mmol), stirred at 30° C. for 3 h, and spin-dried the organic solvent to obtain a yellow solid, which was vacuum-dried at 50° C. to obtain the imidazole polymer iron salt ionic liquid.

Embodiment 3

[0042] Preparation of compound 5-(D-3'-alanine)phenyltetrazolium:

[0043] Add 0.25g D-3-cyanophenylalanine (2.5mmol) successively in 250mL three-necked flask, 0.32g sodium azide (5.5mmol), the 0.07g imidazole polymer iron salt ionic liquid that embodiment 1 prepares and dry 5mL DMF, install a stirrer, a reflux condenser, and a thermometer, raise the temperature to 120°C while stirring, and react at a constant temperature for 24h. Cool, filter and separate the catalyst, wash the catalyst three times with 5 mL of ethyl acetate, dry it and save it for reuse, adjust the pH of the separation liquid to neutral with 6N hydrochloric acid, extract and separate the liquid with 30 mL of ethyl acetate, take the upper organic phase, wash it with 20 mL of water for two After three times, the organic solvent was spin-dried to obtain a white solid, which was dried in vacuum at 50°C and weighed. The yield was 80%, and the chiral purity was 90%.

technical field

[0001] The invention relates to a method for preparing chiral amino acid tetrazole compounds, belonging to the technical field of chemical intermediate synthesis. Background technique

[0002] Tetrazolium is a class of nitrogen-containing heterocyclic substances with a wide range of uses, and has important applications in medicine, pesticides and material science. Chiral amino acid derivatives have broad application prospects in disease treatment, photoluminescence, asymmetric catalysis, etc. The traditional synthesis method mainly uses nitrile and sodium azide as raw materials, and is synthesized under Lewis acid catalysis, but the yield Not high, especially the preparation of chiral amino acid tetrazole compounds will be racemized. Contents of the invention

[0003] Purpose of the invention: the technical problem to be solved by this invention is to provide a method for preparing chiral amino acid tetrazole compounds for the deficiencies in the prior art...

Examples

Embodiment 1

[0034] Preparation of imidazole polymer iron salt ionic liquid

[0035] Add vinylimidazole (5mmol) into a three-necked flask, then add chlorobutane (5mmol), and stir at 40°C for 12h to obtain 1-vinyl-3-n-butynylimidazolium chloride.

[0036] Weigh 0.94g of 1-vinyl-3-n-butyrylimidazolium chloride (5mmol) and dissolve it in 5mL of methanol, add 0.05g of dibenzoyl peroxide, stir at 60°C for 15h, cool down to 50°C, add 0.85g anhydrous FeCl 3 (5 mmol), stirred at 50° C. for 0.5 h, and spin-dried the organic solvent to obtain a yellow solid, which was vacuum-dried at 50° C. to obtain an imidazole polymer iron salt ionic liquid.

Embodiment 2

[0038] Preparation of imidazole polymer iron salt ionic liquid

[0039] Add vinylimidazole (5mmol) into a three-necked flask, then add chlorobutane (15mmol), and stir at 80°C for 5h to obtain 1-vinyl-3-n-butynylimidazolium chloride.

[0040] Weigh 0.94g of 1-vinyl-3-n-butyrylimidazolium chloride (5mmol) and dissolve it in 45mL of methanol, add 0.01g of dibenzoyl peroxide, stir at 90°C for 6h, cool down to 30°C, add 0.42g anhydrous FeCl 3 (2.5 mmol), stirred at 30° C. for 3 h, and spin-dried the organic solvent to obtain a yellow solid, which was vacuum-dried at 50° C. to obtain the imidazole polymer iron salt ionic liquid.

Embodiment 3

[0042] Preparation of compound 5-(D-3'-alanine)phenyltetrazolium:

[0043] Add 0.25g D-3-cyanophenylalanine (2.5mmol) successively in 250mL three-necked flask, 0.32g sodium azide (5.5mmol), the 0.07g imidazole polymer iron salt ionic liquid that embodiment 1 prepares and dry 5mL DMF, install a stirrer, a reflux condenser, and a thermometer, raise the temperature to 120°C while stirring, and react at a constant temperature for 24h. Cool, filter and separate the catalyst, wash the catalyst three times with 5 mL of ethyl acetate, dry it and save it for reuse, adjust the pH of the separation liquid to neutral with 6N hydrochloric acid, extract and separate the liquid with 30 mL of ethyl acetate, take the upper organic phase, wash it with 20 mL of water for two After three times, the organic solvent was spin-dried to obtain a white solid, which was dried in vacuum at 50°C and weighed. The yield was 80%, and the chiral purity was 90%.

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