Category: Pyrazines

Application of 24241-18-7, A common heterocyclic compound, 24241-18-7, name is 2-Amino-3,5-dibromopyrazine, molecular formula is C4H3Br2N3, 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.

18b (3.0 g, 12 mmol) was added into acetic acid (20 mL) and concentrated sulfuric acid (4 mL) under ice bath. To this mixture was added a pre-prepared solution of NaNO2 (1.65 g, 24 mmol) in water (10 mL). The reaction mixturewas stirred at room temperature for 3 h, and then poured into ice water (100 g). The precipitate was collected by filtrated, washed with water and dried to give an off-white solid (1.8 g, yield 61%). 3,5-Dibromo-2-hydroxylpyrazine (21b)Yield: 61%, off-white solid, M.p.: 182-184 C. 1H NMR(400 MHz, CDCl3):delta 11.23 (br, 1H), 7.53 (s, 1H). 1HNMR (400 MHz, DMSO-d6): delta 13.16 (s, 1H), 7.94 (s, 1H).13C NMR (125 MHz, CD3OD): delta 154.19, 136.73, 131.57, 114.62. ESI-MS m/z: 250.9 [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.

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. 22047-25-2, name is Acetylpyrazine, This compound has unique chemical properties. The synthetic route is as follows., name: Acetylpyrazine

A magnetic stirrer is added to the 250ml single-mouth eggplant bottle.Then add 1.85 g of p-bromobenzaldehyde, 2.44 g of 2-acetylpyrazine and 40 ml of ethanol.After stirring to completely dissolve, add 0.40 g of NaOH and 30 ml of concentrated ammonia water, and stir at room temperature for 6 hours.Filtration under reduced pressure, the filter cake was washed with ethanol and deionized water, and dried in vacuo to give Intermediate 4 as white solid, yield 1.75 g, yield 44.1%.The product was not further purified and the next reaction was carried out directly.

According to the analysis of related databases, 22047-25-2, 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. 1082843-70-6, name is 3,5-Dibromo-2-chloropyrazine, A new synthetic method of this compound is introduced below., COA of Formula: C4HBr2ClN2

To a scintillation vial containing 3,5-dibromo-2-chloropyrazine (1 g, 3.67 mmol) and TEA (1 .024 ml, 7.34 mmol) was added MeCN (5 ml) and (tetrahydro-2H-pyran-4- yl)methanamine (0.557 g, 3.67 mmol). The homogenous reaction mixture was capped, and heated to 80 C in a oil bath for 4 hr. The reaction mixture was concentrated to dryness, diluted with EtOAc and sequentially washed with sat NaHC03, and sat NaCI. The organic layer was dried Na2S04, filtered and concentrated. The crude was purified by column chromatography on silica gel ( 20%EtOAc/Hexane) to yield 6-bromo-3-chloro- N-((tetrahydro-2H-pyran-4-yl)methyl)pyrazin-2-amine (688 mg, 2.244 mmol, 61 .1 % yield), yield), LCMS (m/z): 308.0 (MH+), retention time = 0.94 min, and 6-bromo-5- chloro-N-((tetrahydro-2H-pyran-4-yl)methyl)pyrazin-2-amine (55 mg, 0.179 mmol, 4.89 % yield), LCMS (m/z): 308.0 (MH+), retention time = 0.91 min

The synthetic route of 1082843-70-6 has been constantly updated, and we look forward to future research findings.

Electric Literature of 74290-69-0, 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. 74290-69-0, name is 5-Bromo-6-methylpyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a solution of 5-bromo-6-methylpyrazin-2-amine (300 mg, 1.6 mmol, 1.0 eq) in NMP (12 mL) was added CuCN (287 mg, 3.2 mmol, 2.0 eq). The suspension was heated at 200 C for 1 h in microwave. The reaction mixture was cooled to 25 C, mixed with water (20 mL), NH3.H2O (10 mL) and extracted with EA (10 mL x 3). The combined organic layers were washed with brine (10 mL), dried over anhydrous Na2S04 and concentrated. The residue was purified via flash chromatography to afford 5-amino-3-methylpyrazine-2- carbonitrile as a brown solid (210 mg, 98%).

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, 5-Bromo-6-methylpyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Application of 4774-14-5, A common heterocyclic compound, 4774-14-5, name is 2,6-Dichloropyrazine, molecular formula is C4H2Cl2N2, 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.

Step 1 [0665] To a solution of fert-butyl azetidin-3-ylcarbamate hydrochloride (LXIII) (2 g, 9.58 mmol) in dry DMF (19.2 mL) was added DIPEA (8.37 ml, 47.9 mmol). To this mixture was added 2,6-dichloropyrazine (LXIV) (1.428 g, 9.58 mmol) and the reaction was stirred at 95C for 3 h. The reaction was quenched with water (20 mL) and extracted with EtOAc. The organic layer was dried over anhydrous NaaSO/t, filtered and concentrated. The residue was purified by silica gel column chromatography (40 g) (100% hexanes?hexanes:EtOAc 1 : 1) to yield fert-butyl (l -(6-chloropyrazin-2-yl)azetidin-3-yl)carbamate (LXV) (2.2882 g, 8.04 mmol, 84 % yield) as a

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 109838-85-9, 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. 109838-85-9, name is (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine, This compound has unique chemical properties. The synthetic route is as follows.

To a solution of (2R)-(-)-2,5-dihydro-3,6-dimethoxy-2-isopropylpyrazine (0.61 g, 4.36 mmol) in THF (8 mL) was added n-BuLi (2.5 M in hexane, 1.8 mL, 4.58 mmol) at -78 °C. After allowed to stir for 0.3 hours, Compound Int-15a (2.75 g, 6.98 mmol) in 2 mL of THF was added and the mixture was allowed to stir at the temperature for 4 hours. The reaction was quenched by saturated aqueous NH4CI solution and the organic layers were extracted with EtOAc. The combined organic solution was washed with brine solution, dried (Na2S04), and concentrated in vacuo. The residue obtained was purified using an ISCO 40 g column (gradient from 0percent to 2.5percent ether in hexane) to provide Compound Int-15b, 783 mg (44percent). NMR (CDC13) delta 4.05 (m, 1H), 3.96 (t, J = 3.4 Hz, 1H), 3.72 (s, 3H), 3.71 (s, 3H), 3.49 (dd, J = 2,8, 0.4 Hz, 1H), 3.26 (dd, J= 6, 9.4 Hz, 1H), 2.30 (m, 1H), 1.96 (m, 1H), 1.60 (m, 2H), 1.37 1.17 (m, 3H), 1.08 (d, J= 6.9 Hz, 3H), 0.99 0.86 (m, 2H), 0.72 (d, J= 6.6 Hz, 3H), 0.49 (dd, J= 11.0, 14.4 Hz, 1H), 0.35 (dd, J= 11.0, 14.2 Hz, 1H), 0.16 (s, 6H).

The chemical industry reduces the impact on the environment during synthesis (R)-2-Isopropyl-3,6-dimethoxy-2,5-dihydropyrazine. I believe this compound will play a more active role in future production and life.

69214-33-1, name is 8-Chloroimidazo[1,2-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. category: Pyrazines

Example A15Mixture of 3-bromo-8-chloro-imidazo[1,2-c]pyrazine and 3,8-dibromo-imidazo[1,2-a]pyrazine N-Bromosuccinimide (2.0 g, 11.6 mmol) was added to a stirred solution of intermediate 3 (1.78 g, 11.58 mmol) in DCM (50 ml). The mixture was stirred at RT for 2 h. and then diluted with further DCM and washed with a saturated solution of sodium carbonate. The organic layer was separated, dried (Na2SO4), filtered and the solvent evaporated in vacuo to yield a 72/28 mixture of 3-bromo-8-chloro-imidazo[1,2-c]-pyrazine and 3,8-dibromo-imidazo[1,2-a]pyrazine (intermediate 15) (5.89 g, 99%) as white solid.

The synthetic route of 69214-33-1 has been constantly updated, and we look forward to future research findings.

Adding a certain compound to certain chemical reactions, such as: 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, 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 16298-03-6, COA of Formula: C6H7N3O2

(iii) Methyl 3-amino-6-bromopyrazine-2-carboxylate: 3-Aminopyrazine-2-carboxylic acid methyl ester (200 g, 1.3 mol, 3B ScientificCorporation) was dissolved in AcOH (1 L). The solution was warmed to 50 °C and Br2 (312 g, 1.9 mol) added dropwise. When the addition was completed, the mixture was stirred at 50 °C for additional 3 hours. The reaction mixture was poured slowly to ice-water (4 L). The precipitate was filtered, washed with water and dried under a reduced pressure to afford the subtitle compound (iii) as a red brown solid (300g).1H-NMR (400 MHz, CDC13) delta 8.28 (s, 1H), 3.97 (s, 3H);HPLC Retention Time = 1.016min.

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 2-aminopyrazine-3-carboxylate, other downstream synthetic routes, hurry up and to see.

Electric Literature of 6966-01-4,Some common heterocyclic compound, 6966-01-4, name is Methyl 3-amino-6-bromopyrazine-2-carboxylate, molecular formula is C6H6BrN3O2, 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.

(Step 8-iv) Methyl 3-amino-6-bromopyrazine-2-carboxylate (700 mg, 3 mmol) was dissolved in dioxane (4 mL) with 3-furan boronic acid (0.36 g, 3.2 mmol), potassium acetate (980 mg 10 mmol) and tetrakispalladium triphenylphosphine (200 mg, 0.17 mmol) in a microwave vessel. Nitrogen was bubbled through for 5 minutes, followed by sealing the vessel and microirradiating the mixture for 20 minutes at 170 0C. The reaction mixture was diluted with ethyl acetate/saturated sodium bicarbonate, dried over sodium sulfate, and concentrated to give a solid, which was purified by silica gel column chromatography (0 to 70 % EtOAc/hexanes) to give methyl 3-amino-6-(furan-3- yl)pyrazine-2-carboxylate as a solid. This methyl ester was dissolved in THF/MeOH and an aqueous solution of LiOH hydrate (150 mg, 3.6 mmol) was added. The reaction mixture was stirred for 1 hour at room temperature, concentrated to half the volume, and diluted with ethyl acetate/10% aqueous citric acid solution. The organic layer was washed with brine, dried, and concentrated in vacuo to yield 3-amino-6-(furan-3-yl)pyrazine-2- carboxylic acid as a solid (0.46 g, 2.3 mmol, 77 % overall yield).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Methyl 3-amino-6-bromopyrazine-2-carboxylate, its application will become more common.

Reference of 1286754-14-0,Some common heterocyclic compound, 1286754-14-0, name is Ethyl imidazo[1,2-a]pyrazine-3-carboxylate, molecular formula is C9H9N3O2, 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.

The imidazo [1,2 – the a] pyrazine -3 – carboxylic acid ethyl ester (780 mg, 4 . 08 mmol) is dissolved under stirring 20 ml in tetrahydrofuran, then add 10% palladium carbon 400 mg, hydrogen under the protection of the 35 C stirring 12 hours, the reaction to remove the catalyst, concentrated under reduced pressure, column chromatography purification to obtain 5, 6, 7, 8 – tetrahydro imidazo [1,2 – the a] pyrazine -3 – carboxylic acid ethyl ester (600 mg, yield: 75.3%, white solid).

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