Month: April 2021

Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 1256921-67-1, name is Methyl 6-bromo-3-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., category: Pyrazines

Step 11-1, Preparation of methyl 6-bromo-3-[(2R)-4-[(tert-butoxy)carbonyl]-2-ethylpiperazin-1-yl]pyrazine-2-carboxylate To a 15-mL pressure tube vessel, was placed 6-bromo-3-chloropyrazine-2-carboxylic acid methyl ester (300 mg, 1.19 mmol), tert-butyl (3R)-3-ethylpiperazine-1-carboxylate (370 mg, 1.72 mmol, 1.4 equiv), DIEA (0.3 mL, 1.78 mmol, 1.5 equiv), and DMSO (6 mL). The resulting solution was stirred at 140 C. for 1 h, cooled to rt, and diluted with EtOAc (?15 mL). The organic layer was washed with 1N HCl (2*) and brine (1*), dried with anhydrous Na2SO4, and concentrated. The residue was purified from C18 reversed phase column chromatography eluting with 0.1% TFA-ACN/0.1% TFA-H2O. 140 mg (27%) of methyl 6-bromo-3-[(2R)-4-[(tert-butoxy)carbonyl]-2-ethylpiperazin-1-yl]pyrazine-2-carboxylate was isolated. LCMS (M+H)+: 429.3.

The synthetic route of 1256921-67-1 has been constantly updated, and we look forward to future research findings.

Adding a certain compound to certain chemical reactions, such as: 4858-85-9, name is 2,3-Dichloropyrazine, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 4858-85-9, Recommanded Product: 2,3-Dichloropyrazine

Hydrazine hydrate (20 mL, 43.6 mmol) was slowly added dropwise to a solution of 2,3-dichloropyrazine (3.2 g, 21.8 mmol) in ethanol (600 mL).The temperature was raised to reflux for 1.5 hours, and the mixture was dried under reduced pressure.The solid is added to the water and filtered.The solid was recrystallized twice in ethanol to give a yellow solid(2.68 g, yield 85%).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2,3-Dichloropyrazine, and friends who are interested can also refer to it.

Related Products of 19745-07-4, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 19745-07-4 name is 2,5-Dichloropyrazine, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.

A mixture of A-63 (1 g, 6.71mmol), [4-(trifluoromethoxy)phenyl]- boronic acid (1.52 g, 7.38 mmol), Pd(dppf)Cl2.CH2Cl2 (822.23 mg, 1.01 mmol) and Cs2C03 (4373.74 mg, 13.42 mmol) in 1,4-dioxane (20 mL) and water (4 mL) under N2 was stirred at 90 C for 16 hours. After cooling, the reaction mixture was diluted with EtOAc (20 mL), and filtered through a Celite pad, eluted with EtOAc (20 mL), and concentrated. The residue was purified by flash chromatography on silica gel (EtOAc in PE = 0percent to 3percent to 8percent) to afford A-108 (250 mg, 0.91 mmol) as a solid. 1H NMR (400MHz, CDC13) _ = 8.79 (d, 1H), 8.65 (d, 1H), 8.05 (d, 2H), 7.37 (d, 2H)

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2,5-Dichloropyrazine, and friends who are interested can also refer to it.

Electric Literature of 4949-13-7,Some common heterocyclic compound, 4949-13-7, name is 2-Fluoropyrazine, molecular formula is C4H3FN2, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

n-Butyllithium (2.5M in hexanes, 1.05 mL, 2.58 mmol) was added to a solution of 2,2,6,6-tetramethylpiperidine (462 muL, 2.73 mmol) in THF (10 mL) at -78 C. The reaction mixture was stirred at 0 C. for 20 min. A solution of 2-fluoropyrazine (224 mg, 2.28 mmol) in THF was added at -78 C. After stirring at -78 C. for 5 min, ZnCl2 (0.5 M in THF, 11 mL, 5.32 mmol) was then added. The reaction mixture was stirred at -78 C. for 30 min and then at 0 C. for 1 h. A solution of the bromide (500 mg, 1.52 mmol) and Pd(PPh3)4 (352 mg, 0.304 mmol) in THF (20 mL) was then added. The reaction mixture was stirred at rt for 3 days. A sat. aq. solution of EDTA was added. After stirring at rt for 15 min, a sat. aq. solution of NaHCO3 was added. The reaction mixture was extracted with DCM. The combined organics were separated, dried (MgSO4), filtered and concentrated. The crude residue was purified by SiO2 chromatography eluting with 20:80 EtOAc/hexane to afford 200 mg (38%) of pyrazine as a yellow oil. MS m/z (ES): 346 (M+H)+.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Fluoropyrazine, its application will become more common.

Electric Literature of 72788-94-4,Some common heterocyclic compound, 72788-94-4, name is 2-Chloro-5-(hydroxymethyl)pyrazine, molecular formula is C5H5ClN2O, traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

To a solution of (5-chloropyrazin-2-yl)methanol (750 mg, 5.2 mmol) and DIPEA (1.34 g, 10.4 mmol) in dichloromethane (10 mL) was added methanesulfonyl chloride (1.18 g, 10.4 mmol) dropwise at 0 C. The resulting mixture was stirred at r.t. for 0.5 hr. The mixture was diluted with ethyl acetate (30 mL) and washed with water, dried over sodium sulfate, filtered and concentrated under reduced pressure to give (5- chloropyrazin-2-yl)methyl methanesulfonate (800 mg). MS (ESI): m/z 223, 225 (M+H)+

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Chloro-5-(hydroxymethyl)pyrazine, its application will become more common.

Electric Literature of 939412-86-9, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

Intermediate 17&18. Step 3: (6R.8aS)-N-((3-chloropyrazin-2-yl)methyl)-l-methyl-3-oxohexahydro-lH-oxazolor3.4- alpyridine-6-carboxamide To a solution of (6R,8aS)-l-methyl-3-oxohexahydro-lH-oxazolo[3,4-a]pyridine-6-carboxylic acid (600 mg, 3.02 mmol) in dry DCM (12 mL) at 5 C, Oxalyl dichloride (1.15 g, 9.04 mmol) was added drop wise and DMF (3 drops) was added. The reaction mixture was stirred at 30 C for 2 h. The reaction mixture was concentrated in vacuo to give crude acyl chloride. The solution of crude acyl chloride in DCM (3 ml) was added to a solution of (3-chloropyrazin-2- yl)methanamine hydrochloride (594 mg, 3.32 mmol), TEA (640 mg, 6.04 mmol) in DCM (10 ml), and then the reaction mixture was stirred at 30 C for 12h. The reaction was dulited with DCM (20 mL) and H20 (20 mL), the organic layer was washed with brine (20 mL), dried over Na2SC>4, The crude product was purified by column chromatography on silica gel eluted with PE/THF (100 %-40 %) to give (6R,8aS)-N-((3-chloropyrazin-2-yl)methyl)-l-methyl-3- oxohexahydro-lH-oxazolo[3,4-a]pyridine-6-carboxamide. l NMR (400MHz, CD3OD) delta = 8.55 (d, J=2.5 Hz, 1H), 8.36 (d, J=2.5 Hz, 1H), 4.77 (quin, J=6.8 Hz, 1H), 4.65 (s, 2H), 4.30 (quin, J=6.2 Hz, 1H), 3.98 – 3.90 (m, 1H), 3.78 – 3.70 (m, 1H), 3.12 – 3.00 (m, 1H), 2.51 (ttd, J=4.1, 12.1, 16.0 Hz, 1H), 2.19 – 2.07 (m, 1H), 2.00 (dd, J=3.5, 13.1 Hz, 1H), 1.81 – 1.66 (m, 2H), 1.55 – 1.39 (m, 3H), 1.35 (d, J=6.5 Hz, 2H) ppm.

The synthetic route of (3-Chloropyrazin-2-yl)methanamine hydrochloride has been constantly updated, and we look forward to future research findings.

486460-21-3, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine, belongs to pyrazines compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. Recommanded Product: 486460-21-3

Example 19E (66 mg, 0.18 mmol), 3-trifluoromethyl-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine (prepared as described in D. Kim et al, J. Med. Chem. 2005, 48, 141-151). 41.6 mg, 0.216 mmol), and triethyl amine (62.6 mL, 0.45 mumol) were mixed in 1 mL of methylene chloride and stirred for two days. The mixture was then purified by flash chromatography (eluting with 60-70% ethyl acetate/hexane) to give the desired nitro amine.

The synthetic route of 486460-21-3 has been constantly updated, and we look forward to future research findings.

Application of 1082843-72-8, A common heterocyclic compound, 1082843-72-8, name is 6-Bromo-3-chloropyrazin-2-amine, molecular formula is C4H3BrClN3, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.

[0957] Into a 2 L 4-necked round-bottom flask, purged andmaintained with an inert atmosphere ofnitrogen, was placeda solution of compound 90e (42.8 g, 206 mmol) in 1,4-dioxane (1 L), compound 90b (80.0 g, 206 mmol), Pd(dppf)Cl2 (7.53 g, 10.3 mmol) andCs 2C0 3 (167 g, 514 mmol). Thereaction mixture was stirred overnight at 90 C. Upon cooling, the reaction was quenched with water (100 mL). Theresulting mixture was extracted with DCM. The combinedorganic layers were dried over Na2S04 , filtered and concentrated underreduced pressure. The resultant residue was purified by flash column chromatography on silica gel (DCM/MeOH (1 00:3 v/v)) to obtain compound 90fas a yellow solid(23.0 g, 29% yield). Mass Spectrum (LCMS, ESI pos.):Calcd. for C18H23ClN60 2 : 391.2 (M+H). found 391.1.

The synthetic route of 1082843-72-8 has been constantly updated, and we look forward to future research findings.

Adding a certain compound to certain chemical reactions, such as: 22047-25-2, name is Acetylpyrazine, belongs to pyrazines compound, can increase the reaction rate and produce products with better performance than those obtained under traditional synthetic methods. Here is a downstream synthesis route of the compound 22047-25-2, Recommanded Product: Acetylpyrazine

According to a method based on literature [16], we made some modifications. 2-acetylpyrazine (1.22g, 10mmol) and 4-hydroxybenzohydrazide (1.52g, 10mmol) were mixed with 10mL of DMSO. The solution mixture was refluxed at 75C for 4h, and was after that cooled down, filtered, and washed with cold ethanol. Two grams of product (78% yield) were obtained by air-drying. MS, NMR, IR, and UV data are shown in the Supporting information (Section S1).

In the field of chemistry, the synthetic routes of compounds are constantly being developed and updated. I will also mention this compound in other articles, Acetylpyrazine, other downstream synthetic routes, hurry up and to see.

In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 21279-62-9 as follows. Quality Control of 3-Chloropyrazine-2-carboxamide

General procedure: The starting compound (1.27 mmol) was treated with 18 aliphatic amines, alicyclic amines or saturated heterocycles containing at least one nitrogen atom (2.54 mmol). Four reactions were completed by conventional heating methods. The conditions were 110 C, toluene as a solvent and pyridine (1.27 mmol) as a base. The reaction time was set to one hour. Then the reactions were completed using the microwave reactor with focused field and conditions used for syntheses were 140 C, 30 min,120 W, methanol used as a solvent and pyridine (1.27 mmol) as a base. They were set experimentally with respect to prior experience. The progress of reaction was monitored with TLC in system hexane/ethyl acetate (1:1). Then the mixture was separated by flash column chromatograph using gradient elution. Mobile phases were hexane and ethyl acetate again.

According to the analysis of related databases, 21279-62-9, the application of this compound in the production field has become more and more popular.