Category: Pyrazines

Application of 875781-43-4, A common heterocyclic compound, 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, molecular formula is C6H4BrN3, 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.

A 10 mL microwave vial was charged with 5-bromo-4,7-diazaindole (0.471 g, CASRN 875781-43-4), 4-pyridylboronic acid (0.58 g), lM Na2C03 (3 mL), l,l ‘-(dppf)Pd(II)Ci2 (0.097 g) and MeCN (3 mL), capped and irradiated in a microwave reactor at 150 C for 30 min. The reaction was cooled and partitioned between H20 and EtOAc. The aqueous layer was twice washed with EtOAc. The combined organic layers were washed once with brine, dried (MgS04), filtered and concentrated to afford a solid residue. The crude purified by Si02 chromatography eluting with an EtOH/EtOAc gradient (1 to 20% EtOH over 12 min) to afford 0.28g of pure 2- (pyridin-4-yl)-5H-pyrrolo[2,3-b]pyrazin (22).

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.

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. 1458-01-1, name is Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Formula: C6H7ClN4O2

General procedure: Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate 2 (1 eq.) was combined with K2CO3 (10 eq.), the appropriate (het)aryl boronic acid (1.5 eq.) and Pd(PPh3)4 (5 mol%) in a two-neck round bottom flask. The flask was connected to a condenser and purged with nitrogen. A 4:1 mixture of anhydrous toluene: MeOH (60 mL) was added via syringe and the reaction mixture was heated at reflux for 0.5-18 h. The mixture was allowed to cool to room temperature and filtered through Celite (10 x 3 cm, eluting with 3 x 20 mL EtOAc). The filtrate was evaporated to dryness and the residue purified by silica gel flash column chromatography using EtOAc/pet spirit.

The synthetic route of 1458-01-1 has been constantly updated, and we look forward to future research findings.

Synthetic Route of 143591-61-1,Some common heterocyclic compound, 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, molecular formula is C6H3BrClN3, 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.

Intermediate Example 3-1 : Preparation of 3-bromo-8-methylsulfanyl- imidazo[1 ,2-a]pyrazine To a stirred solution of 3-bromo-8-chloro-imidazo[1 ,2-a]pyrazine ( 1 1 .63 g, 50 mmol) in 120 mL NMP is added at -15C under stirring sodium thiomethylate (3.52 g, 50 mmol) After stirring for 4 h the mixture is left to come to rt and stirred overnight. 500 mL of water are added and the light brown solid is filtered off, washed and dried in vaccuo to yield 8.81 (72 %) of the title compound. UPLC-MS: RT = 0.93 min; m/z 245.1 [MH+]; required MW = 244.1.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, its application will become more common.

These common heterocyclic compound, 356783-16-9, name is 3,6-Dichloropyrazine-2-carbonitrile, 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. Recommanded Product: 3,6-Dichloropyrazine-2-carbonitrile

REFERENTIAL EXAMPLE II-15 In 50 mL of N,N-dimethylformamide was dissolved 10.0 g of 3,6-dichloro-2-pyrazinecarbonitrile. After adding 6.49 mL of thiophenol and 11.91 g of potassium carbonate successively, the mixture thus obtained was stirred at 40 C. for 3 hours. The reaction mixture was poured into a mixture of 100 mL of ethyl acetate and 100 mL of water, and pH was adjusted to 2 with 6 mol/L hydrochloric acid. The organic layer was separated, washed successively with water and saturated aqueous solution of sodium chloride, and dried on anhydrous magnesium sulfate, and then the solvent was removed under reduced pressure. The residue thus obtained was purified by silica gel column chromatography [eluent: toluene:n-hexane=1:3] to obtain 3.80 g of 6-chloro-3-(phenylsulfanyl)-2-pyrazinecarbonitrile as a light yellow-colored oily product. R (neat) cm-1: 2238 H-NMR (CDCl3) delta: 7.00-7.70(5H,m), 8.39(1H,s)

The synthetic route of 3,6-Dichloropyrazine-2-carbonitrile has been constantly updated, and we look forward to future research findings.

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. 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, A new synthetic method of this compound is introduced below., Product Details of 5521-55-1

A mixture of 5-methyl-2-pyrazinecarboxylic acid (1) (0.01 mol) and hydrazine hydrate (0.025 mol) in ethanol (20 mL) was refluxed for 9 h on consistent stirring. After completion of the reaction (monitored by the TLC), the reaction mixture is cooled to room temperature, poured in ice-cold water (20 mL). Thus the solid separated was filtered off and the crude product was recrystallized from ethyl acetate to give pure 5-methyl-2-pyrazinecarboxylic acid hydrazide (2).

The synthetic route of 5521-55-1 has been constantly updated, and we look forward to future research findings.

Electric Literature of 6966-01-4, These common heterocyclic compound, 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, 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 250 ml reaction flask add 43g III, 43 ml 98.3% concentrated sulfuric acid, stirring. – 20 – 0 C lower, adding 25.6g sodium nitrite, canada finishes rose to 55 – 60 C, thermal insulation stirring for about 30min to the raw basic reaction end. The reaction liquid dropping 430g ice water, canada finishes insulation stirring for about 1.5h to the reaction is complete. Filtering, the filter cake 50 C drying by blowing 6h, get 37.6g orange solid IV, yield 87%.

The synthetic route of 6966-01-4 has been constantly updated, and we look forward to future research findings.

Related Products of 939412-86-9, The chemical industry reduces the impact on the environment during synthesis 939412-86-9, name is (3-Chloropyrazin-2-yl)methanamine hydrochloride, I believe this compound will play a more active role in future production and life.

To a stirred suspension of (3-chloropyrazin-2-yl)methanamine hydrochloride (0092) (500 mg, 2.78mmol) in ethyl acetate (10 mL) was added acetic anhydride (315 pL, 3.33 mmol) dropwise, followed by triethylamine (1.16 mL, 8.34 mmol). The mixture was stirred at room temperature for 1 h, and the solvent was removed under reduced pressure. The obtained residue was dissolved in methylene chloride (150 mL) and washed with saturated NaHC03 (2 c 25 mL). The organic phase was evaporated under reduced pressure and was further dried under high vacuum to give the title compound as a beige solid (376 mg, 72.9% yield), which was directly used for the next reaction without further purification. MS (ESI) m/z 186.0507 [M + H]+. 1H NMR (500 MHz, Chloroform-d) d 8.5 (d, J = 2.51 Hz, 1H), 8.3 (d, J = 2.55 Hz, 1H), 4.7 – 4.7 (m, 2H), 2.1 (s, 3H)).

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-Chloropyrazin-2-yl)methanamine hydrochloride, other downstream synthetic routes, hurry up and to see.

Synthetic Route of 5049-61-6, A common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.

A 250ml round bottom flask was charged with 2-aminopyrazine (1Og, O.lmol), N-chlorosuccinimide (14g, O.lmol) and dichloromethane (100ml) under nitrogen. The reaction mixture was refluxed for 5h, then allowed to cool to room temperature. The reaction mixture was filtered though a 1 cm thick celite pad, which was then thoroughly washed with dichloromethane. The EPO organic was concentrated in vacuo and the compound was purified by flash chromatography, using as eluent pentane/EtOAc 0% to 50%, to give the title compound (3g, 22%). IHNMR (CDCl3) 4.5-4.8 (2H, brs), 7.8 (IH, s), 8.0 (IH, s).

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.

Reference of 5049-61-6, A common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.

Method b:; 2-Amino-pyrazine (0.10 g, 1.05 mmol) and NCS (80 mg, 0.60 mmol) were added in a microwave tube with 1.5 mL of the anhydrous CHCl3 and sealed. The tube was placed in the microwave cavity and heated at 70C for 10 min. (70C10M60W300Psi). After the workup, the crude (0.15 g) was purified by FCC (Hexane/DCM/ AcOEt = 1 :1 :1) to afford 35 mg (yield 45%) of the product as yellow solid. 1H NMR (270 MHz; d6-DMSO), delta 7.99 (IH, s, H-6), 7.67 (IH, s, H-3), 6.65 (2H, bs, NH2). m/z (EI-MS): 129 (M+), 99, 94 ([M-Cl]+).; When the distilled chloroform used for the reaction was pre-treated over basic Al2O3, the black polymers formed in the reaction decreased dramatically. When NCS was added slowly into the refluxing 2-aminopyrazine, the product was isolated at 26%. Moreover, when microwave irradiation was used at 70C for 10 min., the yield reached 45% (Figure 4)

The synthetic route of 5049-61-6 has been constantly updated, and we look forward to future research findings.

Related Products of 5521-55-1, 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. 5521-55-1 name is 5-Methylpyrazine-2-carboxylic acid, 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.

To a 250 ml four-necked flask was added 13.8 g of 5-methylpyrazine-2-carboxylic acid and 35.7 g of thionyl chloride, and the mixture was heated with stirringReflux reaction 2h, stop heating, vacuum distillation out of excess thionyl chloride, to be evaporated to dry, cooled to room temperature. The residue is dissolved138 g of dichloromethane, and then 20.4 g of p-aminoethylbenzenesulfonamide was added, and 30.4 g of triethylamine was slowly added with stirring,And then stirred at room temperature for 12 h. Filter, and with a small amount of dichloromethane rinse, dry, the filter cake into the water, with hydrochloric acidPH = 1, stirring for 20min, filtered and washed with water to neutral, the resulting solid at 60 ~ 70 for 12h, you can get29.5 g of a white solid product, 2- [4-aminosulfonyl-phenyl] -ethyl-5-methylpyrazine formamide, yield 92.2%.

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