Month: August 2021

Reference of 58138-79-7, 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. 58138-79-7 name is 2,6-Diiodopyrazine, 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.

STAGE 2: preparation of 2-iodo-6-methoxypyrazine 2,6-Diiodopyrazine (5.0 g, 15 mmol) was added to a solution of sodium methoxide in methanol (prepared from sodium (0.35 g, 15 mmol) and methanol (40 ml)) and the mixture was heated at reflux temperature for 1 hour. After cooling, the solution was diluted with water (200 ml) and extracted with diethylether (3*100 ml). The combined extracts were washed with water, dried over magnesium sulphate and concentrated under reduced pressure to give the product as a white solid (3.5 g, 100percent) m. pt. 35.7-37.2 NMR (90 MHz, CDCl3): b 8.40 (1H, s), 8.16 (1H,s), 3.98 (3H,s). m/z 236(M+), 127, 109 (100percent).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2,6-Diiodopyrazine, and friends who are interested can also refer to it.

Reference:
Patent; Imperial Chemical Industries, PLC; US4975112; (1990); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 6863-73-6, name is 3-Chloropyrazin-2-amine, 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 6863-73-6, HPLC of Formula: C4H4ClN3

2-Amino-3-chloropyrazine 9 (10.0 g, 77.2 mmol) was added to a stirred suspension of NCS (11.6 g, 86.9 mmol) in chloroform (73 mL). The reaction mixture was heated at reflux for 4 h. The solution was cooled and partitioned between chloroform (180 mL) and water (2*50 mL). The organic layer was dried, filtered and concentrated. Flash chromatography on silica, eluting with chloroform, gave 10 (9.66 g, 76%) as a pale yellow solid. Mp 200-202 C; Rf (CHCl3) 0.32; numax (thin film/cm-1) 3411 (NH2), 3019 (Ar CH); (found: C, 28.89; H, 1.71; N, 24.99; C4H3N3Cl2: 0.125(H2O) requires C, 28.90; H, 1.97; N, 25.28%); deltaH (500 MHz; CDCl3) 4.96 (2H, br s, NH2), 7.90 (1H, s, 6-H); deltaC (125 MHz; CDCl3) 131.4, 134.6, 140.0, 150.3; GC-MS m/z 167, 165, 163 (M+), GC tR 2.51 min; purity 98%; HRMS (found: MH+ m/z 163.9782; requires 163.9777).

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it.

Reference:
Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728,16;; ; Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 16298-03-6,Some common heterocyclic compound, 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, molecular formula is C6H7N3O2, 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.

Bromine (3.91 g, 24.46 mmol) was added dropwise to a stirred mixture of 3- aminopyrazine-2-carboxylic acid methyl ester (1.27 g, 8.29 mmol) and hydrobromic acid (4.70 mL, 41.5 mmol) at 00C. A solution of sodium nitrite (1.44 g, 20.9 mmol) in water (6 mL) was then added dropwise. The reaction mixture was stirred for 15 min, brought to pH 8 with NaHCO3 (saturated, aqueous), and extracted with ethyl acetate (80 mL) and chloroform (50 mL). The combined organics were dried over MgSO4 and concentrated in vacuo to give 1.13 g (63%) of an orange oil which solidified on standing. LC-MS m/z 217 (M+H+); RT 1.15 mm.

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

Reference:
Patent; BAYER PHARMACEUTICALS CORPORATION; WO2006/49681; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, 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. COA of Formula: C4H5N3

Step A: 5-bromopyrazin-2-amine: To a solution of pyrazin-2-amine (20 g, 210 mmol) in 1.5 L of DCM was added NBS (37.4 g, 210 mmol) at 0 C. The resulting mixture was stirred for 3 hours at 0 C then filtered through CELITE. The filtrate was washed with saturated Na2C03 and brine, dried over Na2S04 and evaporated to afford a solid. The crude material was purified on silica gel (eluting with 20-40 percent ethyl acetate in hexane) to give 5-bromopyrazin-2- amine.

The synthetic route of Pyrazin-2-amine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK SHARP & DOHME CORP.; DONG, Shuzhi; PASTERNAK, Alex; SUZUKI, Takao; GU, Xin; FU, Qinghong; JIANG, Jinlong; DING, Fa-Xiang; TANG, Haifeng; DEJESUS, Reynalda K.; WO2015/96035; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 33332-28-4, name is 2-Amino-6-chloropyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. COA of Formula: C4H4ClN3

6-Chloro-5-iodo-4-ylpyrazin-2-amine To a O0C cooled stirred solution of 2-amino-6-chloropyrazine (3 g, 23 mmol) in a mixture of DMSO (90 mL) and water (2.2 mL), was added Lambda/-iodosuccinimide (5.2 g, 23 mmol) in EPO portions. After stirring for 72h, the mixture was poured into water, extracted twice with ethyl acetate, the organic layers washed with brine, dried (MgSO4) and evaporated. Flash chromatography (98:2 dichloromethane/methanol) furnished the title compound as a yellow solid (4.43 g, 76%). delta 1H-NMR (CDCI3): 7.73 (s, 1H), 4.72 (s, 2H).ESI/MS (m/e, %): 255 [(M+1) C4H3CIIN3].

The synthetic route of 33332-28-4 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ALMIRALL PRODESFARMA, S.A.; WO2007/17096; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 22047-25-2, name is Acetylpyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. Recommanded Product: 22047-25-2

A solution of acetylpyrazine (5 g, 40.9 mmol) in N, N-dimethylformamide dimethyl acetal (10.9 mL, 81.8 mmol) and Et3N (5.7 mL) was heated at 110C for 16 h. The heating was stopped and a precipitate was formed while it was allowed to cool down to room temperature. The suspension was diluted with tert-butyl methyl ether; the solid was separated by filtration and washed with ter-butyl methyl ether. This material was triturated with the same solvent, filtered off and dried to afford the title compound 23a as a yellow solid (5.9 g, 33.3 mmol, 81% yield).’H NMR (400 MHz, DMSO-d6) 8 (ppm): 9.09 (s, 1H), 8.73 (d, J = 2.4 Hz, 1H), 8.66 (dd, J = 2.4, 1.6 Hz, 1H), 7.84 (d, J = 12.4 Hz, 1H), 6.30-6. 20 (m, 1H), 3.19 (s, 3H), 2.93 (s, 3H).

The synthetic route of 22047-25-2 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; METHYLGENE INC.; WO2005/92899; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 33332-28-4, name is 2-Amino-6-chloropyrazine, This compound has unique chemical properties. The synthetic route is as follows., Recommanded Product: 33332-28-4

To a solution of 6-chloro-pyrazin-2-ylamine (5.0 g, 38.8 mmol) in chloroform (194 mL) was added N-bromosuccinimide (20.7 g, 116 mmol) under a nitrogen atmosphere and the reaction mixture was stirred at room temperature for 5 h. The resulting mixture was poured into an aqueous solution of K2CO3 (300 mL) and extracted with dichloromethane (200 mL x 4). The combined organic extracts were dried and purified by chromatography (silica, 10-20 percent ethyl acetate in hexanes) to give 3,5-dibromo-6-chloro-pyrazin-2-ylamine (4.2 g, 38percent) as a yellow solid. LC-MS: 286.0 (M-H).

According to the analysis of related databases, 33332-28-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; F. HOFFMANN-LA ROCHE AG; HOFFMANN-LA ROCHE INC.; HERMANN, Johannes Cornelius; KENNEDY-SMITH, Joshua; LUCAS, Matthew C.; PADILLA, Fernando; SCHOENFELD, Ryan Craig; WOVKULICH, Peter Michael; WO2014/29732; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 25911-65-3,Some common heterocyclic compound, 25911-65-3, name is 3-Aminopyrazine-2-carbonitrile, molecular formula is C5H4N4, 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.

c) 4-Amino-2-[(3,4-dichlorophenoxy)methyl]pteridine Obtained using the procedure described in section c of Example 2, starting with 9.6 g (0.080 mole) of 3-amino-2-pyrazinecarbonitrile and 26.3 g (0.12 mole) of 2-(3,4-dichlorophenoxy)acetamidine in 520 ml of absolute ethanol. Refluxing time: 3 hours. Yld: 18.0 g (70%), m.p. 261-263 C. (ethanol/N,N-dimethylformamide). NMR (CF3 COOD): delta=5.4 (2H, s); 6.9-7.6 (3H, m); 9.2 (2H, s).

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

Reference:
Patent; Lipha, Lyonnaise Industrielle Pharmaceutique; US5167949; (1992); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 13301-04-7,Some common heterocyclic compound, 13301-04-7, name is Methyl 3,6-dibromopyrazine-2-carboxylate, molecular formula is C6H4Br2N2O2, 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.

General Procedures:Synthesis of compound (B) as described in the general reaction scheme; 3 ,6-dibromo-pyrazine-2- carboxylic acid.[00248] LiOH (655mg, 27mmol) is added to a solution of methyl-3-amino-2-pyrazine carboxylate (A) (J. Med. Chem. 1969, 12, 285-87) (2.7g, 9mmol) in THF:water:MeOH (18:4.5:4.5mL).The reaction is stirred at 50C for 30min, concentrated in vacuo, taken up in DCM and washed with IN HCl. The organic phase is dried over MgSO4 and concentrated in vacuo to afford compound (B). 1H NMR (250MHz, CDCl3) delta(ppm)8.70(lH, s).

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

Reference:
Patent; GALAPAGOS N.V.; WO2007/131991; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 486460-21-3, 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. 486460-21-3, name is 3-(Trifluoromethyl)-5,6,7,8-tetrahydro-[1,2,4]triazolo[4,3-a]pyrazine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below.

EXAMPLE 6ATo a solution of the acid (VII’) (300 mg, 0.90 mmol) and triazolopiperazine (VIII) (170 mg, 0.90 mmol) in CH2CI2 (10 mL) is added /V-hydroxybenzotriazole (150 mg, 1 .08 mmol), and 10 minutes later, EDC (260 mg, 1 .35 mmol). The mixture, under an inert atmosphere of N2, is magnetically stirred for 4 hours until completion, then a saturated solution of sodium bicarbonate (5 mL) is added and the mixture is extracted with dichloromethane.The combined organic phases are dried and evaporated under reduced pressure. The product is purified by flash chromatography, obtaining 406 mg (86% yield) of a crystalline white solid, compound (IX’).1 H NMR (300 MHz, d6-dmso, 100 C) delta 7.4-7.2 (m, 7H), 6.90 (bs, 1 H) 4.97 & 4.90 (AB system, J= 12.9 Hz, 2 x 1 H), 4.92 (s, 2H), 4.26-4.14 (m, 3H), 3.97 (t, J=5.5 Hz, 2H), 2.92 & 2.67 (2 x dd, J=14.1 , 4.9 Hz, 2 x 1 H), 2.83-2.72 (m, 2H).

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, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; CHEMO IBERICA, S.A.; RASPARINI, Marcello; TUFARO, Roberto Rocco; MINELLI, Cosima; WO2012/150328; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem