Month: May 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. 87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, A new synthetic method of this compound is introduced below., Recommanded Product: 87486-34-8

General procedure: To a solution of 2a-j (10 mmol, 1.0 eq) , 3,5-dibromo-1-methylpyrazin-2(1H)-one (2.95 g, 11 mmol, 1.1 eq) and DIEA (3.3 mL,20 mmol, 2.0 eq) in MeCN (20mL) was stirred at 80 °C for 5 hours. After cooling to room temperature, thesolvent was removed in vacuo, and the residue was purified using silica gelchromatography to give the title compounds, yield 72-85percent. methyl3-((6-bromo-4-methyl-3-oxo-3,4-dihydropyrazin-2-yl)amino)-4-methylpe ntanoate(4a): 1H NMR (400 MHz, DMSO-d6) delta 7.35 (d, 1H), 7.03 (s, 1H), 4.18? 4.07 (m, 1H), 3.54 (s, 3H), 3.36 (s, 3H), 2.69 ? 2.55 (m, 2H), 1.94 ? 1.80(m, 1H), 0.92 ? 0.76 (m, 6H). ESI-ms (m/z): 332.0 [M+H]+

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

4858-85-9, name is 2,3-Dichloropyrazine, 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. Quality Control of 2,3-Dichloropyrazine

Step 1: 2-chloro-3-hydrazinylpyrazi [0196] To a stirred solution of 2,3-dichloropyrazine (10.0 g, 67.6 mmol) in ethanol (95%, 120 ml) was added 85% hydrazine hydrate (25.6 mL, 338 mmol) dropwise at room temperature. The mixture was stirred for 4 hours and cooled to ice-water bath temperature. The resulting precipitate was isolated by filtration and washed with cold ethanol (95%) to give the title compound as a light yellow powder (6.5 g, 67%) which was used in the next step without further purification.

The synthetic route of 4858-85-9 has been constantly updated, and we look forward to future research findings.

Synthetic Route of 762240-92-6, The chemical industry reduces the impact on the environment during synthesis 762240-92-6, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, I believe this compound will play a more active role in future production and life.

2,4,5-Trifluorophenylacetic acid (2-1) (150 g, 0.789 mol), Meldrum’s acid (125 g, 0.868 mol), and 4-(dimethylamino)pyridine (DMAP) (7.7 g, 0063 mol) were charged into a 5 L three-neck flask. N,N-Dimethylacetamide (DMAc) (525 mL) was added in one portion at room temperature to dissolve the solids. N,N-diisopropylethylamine (282 mL, 1.62 mol) was added in one portion at room temperature while maintaining the temperature below 40 C. Pivaloyl chloride (107 mL, 0.868 mol) was added dropwise over 1 to 2 h while maintaining the temperature between 0 and 5 C. The reaction mixture was aged at 5 C. for 1 h. Triazole hydrochloride 14 (180 g, 0.789 mol) was added in one portion at 40-50 C. The reaction solution was aged at 70 C. for several h. 5% Aqueous sodium hydrogencarbonate solution (625 mL) was then added dropwise at 20 -45 C. The batch was seeded and aged at 20-30 C. for 1-2 h. Then an additional 525 mL of 5% aqueous sodium hydrogencarbonate solution was added dropwise over 2-3 h. After aging several h at room temperature, the slurry was cooled to 0-5 C. and aged 1 h before filtering the solid. The wet cake was displacement-washed with 20% aqueous DMAc (300 mL), followed by an additional two batches of 20% aqueous DMAc (400 mL), and finally water (400 mL). The cake was suction-dried at room temperature.

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, 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine hydrochloride, other downstream synthetic routes, hurry up and to see.

Related Products of 13924-95-3, The chemical industry reduces the impact on the environment during synthesis 13924-95-3, name is Methyl 5-hydroxypyrazine-2-carboxylate, I believe this compound will play a more active role in future production and life.

2-hydroxy-5-carbomethoxy-pyrazine (15.4 g) was dissolved in phosphorus oxychloride (100 ml) and several drops of dimethylformamide were added, followed by stirring with heating at 140C for 3 hours. After the reaction solution was poured into ice water and extracted with chloroform, the organic layer was washed with an aqueous saturated sodium hydrogen carbonate solution and saturated brine, dried and then concentrated. The resulting crystal was collected by filtration and washed with ether to obtain 2-chloro-5-carbomethoxy-pyrazine (14.0 g).

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, Methyl 5-hydroxypyrazine-2-carboxylate, other downstream synthetic routes, hurry up and to see.

Related Products of 121246-96-6, 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. 121246-96-6 name is 3-Chloropyrazine-2-carbaldehyde, 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.

Preparation 1; 4-Methyi-3,4,5,6-tetrahydro-2H-[1,2’lbip(at)rrazinyl-3′-carbaldehyde; n-BuLi (56 mmol, 22.4 mL, 2.5 M in hexanes) was added to tetrahydrofuran (300 mL) cooled to-78 C followed by the addition of 2,2-6,6-tetramethylpiperidine (52 mmol, 8.71 mL). The solution was removed from the cooling bath and stirred for 30 minutes and then cooled back to -78C. 2-chloropyrazine (40 mmol, 3.65 mL) was added dropwise, and the solution turned a reddish-brown color. After stirring 30 minutes, methylformate (60 mmol, 3.7 mL) was added and the reaction mixture was stirred for 2.25 hrs at -78C. Acetic acid (8 mL) was added and the mixture was warmed to 0C, was washed 3 times with 1: 1 brine-water, dried over sodium sulfate, and then concentrated in vacuo. The residue was dissolved in 1,4- dioxane (250 mL) and 1-methylpiperazine (60 mmol, 6.6mL) and potassium carbonate solution (8.28g in 60 mL of water) were added and the mixture was heated at 100C for 1.5 hours. After cooling to room temperature, the mixture was filtered through a Celite pad which was then washed with chloroform. The filtrate was concentrated in vacuo and purified by silica gel chromatography (100: 1:1 chloroform-methanol-ammonium hydroxide) to yield 3.3 g (40% yield for two steps) of 4-methyl-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3′-carbaldehyde; ¹3C NMR (100 MHz, CDC13) d 191.7,154.3, 145.3,134.5, 133.2, 55.1, 48.7, 46.3; MS (AP/CI) 207.2 (M+H)+.

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

Each compound has different characteristics, and only by selecting the characteristics of the compound suitable for a specific situation can the compound be applied on a large scale. 1320266-92-9, name is 8-Chloro-1-iodo-3-isopropylimidazo[1,5-a]pyrazine, This compound has unique chemical properties. The synthetic route is as follows., Quality Control of 8-Chloro-1-iodo-3-isopropylimidazo[1,5-a]pyrazine

Intermediate K (33 mg, 0.10 mmol) and NH4OH were heated to 80 C for 6 h in a microwave. The reaction mixture was concentrated in vacuo and purified using silica gel chromatography with a hexane/EtOAc gradient to yield Intermediate L (33 mg, 66% yield). ¾-NMR (300 MHz, CDC13) delta 1.4 (d, 6H, / = 5.4 Hz), 3.17-3.26 (m, 1H), 5.88 (br s, 2H), 7.02 (d, 1H, J= 5.1 Hz), 7.23 (d, 1H, J= 5.1 Hz). MS (ESI) (M+H)+ 303.2

Chemical properties determine the actual use. Each compound has specific chemical properties and uses. We look forward to more synthetic routes in the future to expand reaction routes of 1320266-92-9.

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 24241-18-7 as follows. Computed Properties of C4H3Br2N3

Intermediate Example 9-1 : Preparation of 6,8-dibromo-imidazo[1 ,2-a]pyrazine To a stirred suspension of 2-amino-3,5-dibrompyrazine (427 g, 1688mmol) in water (6.4 L) / THF (482 ml_), at rt was added bromacetaldehyde-diethylacetal (998 g, 5065 mmol) in one portion. After stirring under reflux for 4 h, the clear orange solution was stirred for an additional 15 h at rt. The suspension was filtered, and the remaining solid was washed with MeOH (2 L) and dried in vaccuo at 60 C to yield 6,8-dibromo-imidazo[1 ,2-a]pyrazine as an off-white solid (500 g, 107% with residual MeOH): 1H-NMR (300 MHz, d6-DMSO): delta =9.02 (s, 1 H), 8.23 (d, 1 H), 7.89 (d, 1 H) ppm. UPLC-MS: RT = 0.80 min; m/z 277.9 [MH+]; required MW = 276.9.

According to the analysis of related databases, 24241-18-7, the application of this compound in the production field has become more and more popular.

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. 6164-79-0, name is Methyl 2-pyrazinecarboxylate, A new synthetic method of this compound is introduced below., Safety of Methyl 2-pyrazinecarboxylate

LiAlH4 (4g, 100 mMol) was slowly added to a solution of pyrazinecarboxylic acid methyl ester (12. 8g, 100 mMol) in tetrahydrofuran (400 mL) at-70° C. The mixture was stirred at this temperature for 40 min, followed by neutralisation with 20 mL of glacial acetic acid. The solvent was evaporated in vacuo and the residue was partitioned between 30 mL of 2N HCL and dichloromethane. A large amount of brown solid precipitated which was filtered off. The dichloromethane layer was passed through a pad of silica, the solvent was evaporated to give the pyrazine 2-carboxaldehyde (1.4g) as a yellow oil.

The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.

Synthetic Route of 50866-30-3, These common heterocyclic compound, 50866-30-3, name is 5-Methylpyrazine-2-carbaldehyde, 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.

To a solution of the BOC-protected intermediate from Example 2 (32 mg, 0.07 mmol) in 1/1 dichloromethane/ methanol (1 mL) was added a solution of 5-methylpyrazine-2-carbaldehyde (11 mg, 0.09 mmol) in 1/1 dichloromethane/methanol (0.3 mL), followed by acetic acid (20 muL, 0.35 mmol) and the mixture was stirred at 50 C. for 15 minutes. MP-cyanoborohydride resin (327 mg, 0.07 mmol) was added and the mixture was shaken at 50 C. overnight, filtered and concentrated. To the residue was added 4M hydrogen chloride in dioxane (2 mL) and the mixture was shaken at 50 C. for 2 hours. The mixture was concentrated, dissolved in 1:1 dimethylsulfoxide/methanol and purified by preparative HPLC (Phenomenex Luna C8(2) 5 mum 100 AXIA column) eluting with a gradient of 5-100% acetonitrile/0.1% trifluoroacetic acid in water to afford the title compound as the trifluoroacetate salt. 1H NMR (400 MHz, pyridine-d5) delta 12.04 (s, 1H) 8.74 (s, 1H) 8.69 (s, 1H) 8.49-8.51 (m, 1H) 8.46 (s, 1H) 7.18 (d, J=7.32 Hz, 1H) 6.91-6.96 (m, 2H) 4.53 (s, 2H) 3.91-4.03 (m, J=8.55 Hz, 1H) 3.63-3.71 (m, J=8.70, 8.70 Hz, 2H) 3.61 (s, 1H) 3.53-3.60 (m, 1H) 3.47 (t, J=8.39 Hz, 2H) 3.07-3.16 (m, 1H) 2.92 (t, J=8.54 Hz, 2H) 2.44 (s, 3H) 2.19-2.27 (m, J=2.44 Hz, 1H) 1.87-2.11 (m, J=28.08 Hz, 2H) 1.76-1.86 (m, J=14.34 Hz, 1H). MS (ESI) m/z 463 (M+H)+.

The synthetic route of 50866-30-3 has been constantly updated, and we look forward to future research findings.

Related Products of 907597-26-6,Some common heterocyclic compound, 907597-26-6, name is 3-Bromoisothiazolo[4,5-b]pyrazine, molecular formula is C5H2BrN3S, 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.

A mixture of 3-bromoisothiazolo[4,5-b]pyrazine (Ark Pharm, catAK-30773: 17 mg, 0.080 mmol), 2-methylbiphenyl-3-amine (Example 11, Step 1: 14.7 mg, 0.080 mmol), [(2-di-cyclohexylphosphino-3,6-dimethoxy-2?,4?,6?-triisopropyl-1,1?-biphenyl)-2-(2?-amino-1,1?-biphenyl)]palladium(II) methanesulfonate (BrettPhos Pd G3, 11 mg, 0.012 mmol), and cesium carbonate (130 mg, 0.40 mmol) in tert-butyl alcohol was purged with nitrogen, and then stirred at 100 C. for 2 h. After being cooled to room temperature, the crude reaction mixture was diluted with methanol and purified by prep HPLC (pH=2, acetonitrile/water+TFA) to provide the desired compound as the TFA salt. LC-MS calculated for C18H15N4S (M+H)+: m/z=319.1; found 319.2.

The synthetic route of 907597-26-6 has been constantly updated, and we look forward to future research findings.