Tag: M.W=100-200

19838-08-5,Some common heterocyclic compound, 19838-08-5, name is 3-Methylpyrazin-2-amine, molecular formula is C5H7N3, 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.

3-Methyl-pyrazin-2-ylamine (2) (109 mg, 1.0 mmol), benzaldehyde (106 mg, 1.0 mmol) and 3-chloro- phenylisonitrile (138 mg, 1.0 mmol) were dissolved in a mixture of dry methanol (2.0 mL) and trimethyl orthoformate (2.0 mL) under argon. The mixture was stirred at 60C for 3 hours, then cooled to rt. An analytically pure sample of 3 was obtained from the crude product using preparative HPLC

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 19838-08-5, its application will become more common.

Reference:
Patent; ESBATECH AG; WO2005/120513; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

55557-52-3, 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 55557-52-3 as follows.

The 3 – chloro -2 – cyanopyrazine (2.24 g 1.6 eq), 4 – amino -2 – pyrimidine formic acid (1.39 g 1 eq) and potassium carbonate (4.1 g 3 eq) solution 20 mLDMF in, stirring and heating to 60 C, reaction 5 h, cooling to room temperature, filter, solution (DCM/MeOH=20:1) for refining, yellow solid product to be 1.73 g (yield: 71%).

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 55557-52-3, and friends who are interested can also refer to it.

Reference:
Patent; Jiangxi Runze Pharmaceutical Co., Ltd.; Liao Niansheng; Zou Mingming; Hu Xiande; Sui Rongchun; Xu Man; (14 pag.)CN108689997; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 123-32-0, name is 2,5-Dimethylpyrazine, molecular formula is C6H8N2, 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. 123-32-0

(b) 3,6-Dimethylpyrazin-2-amine A mixture of 2,5-dimethylpyrazine (14 g, 0.13 mol) in N,N-dimethylaniline (50 mL) was heated to 170 C. and NaNH2 (22 g, 0.56 mol) was added in portions. The reaction mixture was stirred at 170 C. for 1 h, and the solvent was removed. The product was purified by silica gel column chromatography to give 3,6-dimethylpyrazin-2-amine as a brown solid (1.6 g, yield 10%). ESI MS: m/z 124 [M+1]+.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 123-32-0, its application will become more common.

Reference:
Patent; Sunovion Pharmaceuticals Inc.; US2012/178748; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

113305-94-5, Adding some certain compound to certain chemical reactions, such as: 113305-94-5, name is 5-Aminopyrazine-2-carbonitrile, 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 113305-94-5.

Synthesis 2C (R)-tert-Butyl 2-((2-(5-cyanopyrazin-2-ylamino)-5-(trifluoromethyl)pyridin-4-ylamino)methyl)morpholine-4-carboxylate (R)-tert-Butyl 2-((2-chloro-5-(trifluoromethyl)pyridin-4-ylamino)methyl)morpholine-4- carboxylate (1.44 g, 3.64 mmol), 2-amino-5-cyanopyrazine (0.612 g, 5.09 mmol, 1.4 eq.), tris(dibenzylideneacetone)dipalladium(0) (0.267 g, 0.291 mmol, 0.08 eq.), rac-2,2′- bis(diphenylphosphino)-1 ,1 ‘-binaphthyl (0.362 g, 0.582 mmol, 0.16 eq.) and caesium carbonate (2.37 g, 7.28 mmol) were suspended in anhydrous dioxane (33 ml_) under argon. Argon was bubbled through the mixture for 30 minutes, after which the mixture was heated to 100C for 22 hours. The reaction mixture was cooled and diluted with dichloromethane, then absorbed on to silica gel. The pre-absorbed silica gel was added to a 100 g KP-Sil SNAP column which was eluted with 20-50% ethyl acetate in hexanes to give the partially purified product as an orange gum. The crude product was dissolved in dichloromethane and purified by column chromatography on a 90 g SingleStep Thomson column, eluting with 20% ethyl acetate in dichloromethane, to give the title compound (1.19 g, 68%). H NMR (500 MHz, CDCI3) delta 1.50 (9H, s), 2.71-2.88 (1 H, m), 2.93-3.08 (1 H, m), 3.27- 3.32 (1 H, m), 3.40-3.44 (1 H, m), 3.55-3.64 (1 H, m), 3.71-3.77 (1 H, m), 3.82-4.11 (3H, m), 5.33 (1 H, broad s), 7.19 (1 H, s), 8.23 (1 H, s), 8.58 (1 H, s), 8.84 (1 H, s). LC-MS (Agilent 4 min) Rt 2.93 min;m/z (ESI) 480 [MH+].

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 113305-94-5.

Reference:
Patent; CANCER RESEARCH TECHNOLOGY LIMITED; COLLINS, Ian; MATTHEWS, Thomas Peter; FARIA DA FONSECA MCHARDY, Tatiana; OSBORNE, James; LAINCHBURY, Michael; WALTON, Michael Ian; GARRETT, Michelle Dawn; WO2013/171470; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-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. 55557-52-3

General procedure: In a degassed solution of DME/water 2:1 (12mLmmol-1 of diazine), was introduced S-Phos (10mol%) and Pd(OAc)2 (5mol%). The solution was heated at 80C for 10min and sodium carbonate (4equiv), the arylboronic species (1.05 or 1.50equiv) and 3-chloropyrazine-2-carbonitrile (1equiv) were added. The solution was then refluxed (15min or overnight) under argon. The resulting solution was filtrated on celite and washed with ethyl acetate and water. The aqueous phase was then extracted 3 times with ethyl acetate. The combined organic phases were washed with water, dried over MgSO4 and evaporated to dryness. The residue was purified by silica gel chromatography to give the desired product.

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 55557-52-3.

Reference:
Article; Fresneau, Nathalie; Dumas, Noe; Tournier, Benjamin B.; Fossey, Christine; Ballandonne, Celine; Lesnard, Aurelien; Millet, Philippe; Charnay, Yves; Cailly, Thomas; Bouillon, Jean-Philippe; Fabis, Frederic; European Journal of Medicinal Chemistry; vol. 94; (2015); p. 386 – 396;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 123-32-0 name is 2,5-Dimethylpyrazine, 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. 123-32-0

Intermediate 55 2-(chloromethyl)-5-methylpyrazine To a solution of 2,5-dimethylpyrazine (500 mg, 4.62 mmol) in carbon tetrachloride (7 mL) was added NCS (679 mg, 5.09 mmol) followed by BPO (20 mg) and the mixture was heated to 80 C for 6 hours. The mixture was diluted with DCM and extracted with saturated aqueous sodium sulfite solution and brine. The organic layer was dried and concentrated to give a crude product which was purified via silica gel chromatography eluting with petroleum ether/ ethyl acetate (1 :0 to 15: 1) to give 2-(chloromethyl)-5-methylpyrazine (133 mg, 20.19% yield) as yellow oil. LCMS retention time 0.557 min; LCMS MH+ 143.

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

Reference:
Patent; HYDRA BIOSCIENCES, INC.; CHENARD, Bertrand; GALLASCHUN, Randall; WO2014/143799; (2014); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 123-32-0, name is 2,5-Dimethylpyrazine, 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. 123-32-0

The method of preparing 3,6-dimethyl-2- (4-fluoro) benzoyl pyrazine, comprising the steps of:(1) 2,5-dimethyl pyrazine take 0.2mmol, 4- fluoro-benzoyl acid 0.4mmol, silver phosphate 0.02mmol, potassium persulfate 0.4mmol, 1.4mL was added dichloromethane, 0.6mL distilled water was added, and the mixture was placed in a reaction tube in 5mL, 40 oil bath was heated, reaction 24h, cooled to room temperature to obtain a reaction solution;(2) The step (1) the resulting reaction mixture was directly concentrated to give a concentrate, the concentrate with ethyl acetate / petroleum ether = 1/2 (v / v) as the developing solvent, separation by thin layer chromatography to give 34 mg desired product in 74% yield.

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 123-32-0.

Reference:
Patent; Henan Agricultural University; Wu Zhiyong; Zhao Mingqin; Li Yuan; (10 pag.)CN108101856; (2018); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

38557-72-1, Adding a certain compound to certain chemical reactions, such as: 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, 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 38557-72-1.

0.39 g of 2-chloro-3,5-dimethylpyrazine, 0.87 g of 2-(3-diphenylaminophenyl)-1,3,2-dioxaborolane which was obtained in Step 1, 0.30 g of sodium carbonate, 0.013 g of bis(triphenylphosphine)palladium(II) dichloride (abbreviation: Pd(PPh3)2Cl2), 10 mL of water, and 10 mL of acetonitrile in a recovery flask equipped with a reflux pipe. The air in the flask was then replaced by argon. This reaction container was heated by microwave irradiation (2.45 GHz, 100 W) for 20 minutes. After that, the reaction container was cooled to 50 C. or lower. Then, water was added to the reaction solution, and the organic layer was subjected to extraction with dichloromethane. The obtained organic layer was washed with water and dried with magnesium sulfate. After the drying, the solution was filtered. The solvent of this solution was distilled, and the obtained residue was purified by silica gel column chromatography using a mixed solvent of dichloromethane and ethyl acetate as a developing solvent, thereby obtaining the objective pyrazine derivative Hdm5dpappr (white powder, 11% yield). Note that the microwave irradiation was performed using a microwave synthesis system (Discover, produced by CEM Corporation). The synthesis scheme of Step 2 is shown by (b-1).

According to the analysis of related databases, 38557-72-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Semiconductor Energy Laboratory Co., Ltd.; US2012/165523; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Adding a certain compound to certain chemical reactions, such as: 5521-58-4, name is 5-Methylpyrazin-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 5521-58-4, 5521-58-4

DMF (2 drops) was added to a solution of3-{[(LS}1-methyl-2-(methyloxy)ethyl]oxy}-5- [(phenylmethyl)oxy]benzoic acid (6.0 g, 19.0 mmol) and oxalyl chloride (1.99 mL, 22.8 mmol) in DCM (40 mL) The mixture was stirred at ambient temperature for 2 hours and the DCM and excess oxalyl chloride evaporated in vacuo. The residual acid chloride was dissolved in DCM and added dropwise to 2-amino-5 methylpyrazine [Tett lett. 2002, 9287-90] (2.28 g, 19.8 mmol) and pyridine (2.56 mL, 38 mmol) in DCM (40 mL), at 0C. Stirred at ambient temperature for 24 hours. The DCM was evaporated in vacuo, and the residue partitioned between ethyl acetate (100 mL) and IN hydrochloric acid (50 mL). The ethyl acetate layer was washed sequentially with saturated aqueous sodium hydrogen carbonate (50 mL) and brine (50 mL), dried (MgS04), and evaporated in vacuo. The residue was chromatographed on silica, eluting with a gradient of 30-100% ethyl acetate in isohexane, to give the desired compound (7.6 g) ‘H NMR No. (CDC13): 1.32 (d, 3H), 2.55 (s, 3H), 3.40 (s, 3H), 3.50-3.62 (m, 2H), 4.60 (m, 1H), 5.10 (s, 2H), 6.75 (s, 1H), 7.09 (m, 1H), 7.13 (m, 1H), 7.32-7.46 (m, 5H), 8.13 (s, 1 H), 8.38 (s, 1H), 9.55 (s, 1H). m/z 408 (M+H)+

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-Methylpyrazin-2-amine, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; ASTRAZENECA AB; ASTRAZENECA UK LIMITED; WO2005/121110; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

36070-80-1, The chemical industry reduces the impact on the environment during synthesis 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, I believe this compound will play a more active role in future production and life.

The starting 5-chloropyrazine-2-carboxylic acid (317 mg, 2 mmol) was converted to5-aminopyrazine-2-carboxylic acid (1) by substitution reaction with 25% (m/m) aqueous solutionof ammonia (3 mL). The reaction was carried out 10 mL microwave pressurized vials with stirring(reaction temperature: 100 C, reaction time: 30 min, power output: 80 W). The reaction was repeated20 times to yield reasonable quantity of the starting acid. Once the reaction was completed, the vials content was put onto Petri dish and heated above a water bath with intermittent stirring until a drysolid was obtained (ammonium salt of the product). To get the free acid form, the ammonium salt wasdissolved in water and drop-wise acidified with 10% hydrochloric acid to reach pH of 4. The mixturewas then left to cool down in room temperature for 5 min then kept in the fridge for 15 min. The formedfree acid crystals were filtered off by filtration paper with suction and left to dry overnight. After itwas dried, the resulting 5-aminopyrazine-2-carboxylic acid (1) was esterified in several microwavepressurized vials; 3 mL of anhydrous propanol and 2 drops of concentrated sulfuric acid were added to278 mg (2 mmol) of compound 1 in each vial. The esterification was carried out in microwave reactor(reaction temperature: 100 C, reaction time: 1 h, power output: 80 W). The completion of reaction wasmonitored by TLC in system hexane/ethyl acetate (EtOAc) (1:3). The ester was then purified by flashchromatography using gradient elution 40 to 100% EtOAc in hexane.

The chemical industry reduces the impact on the environment during synthesis 5-Chloropyrazine-2-carboxylic acid. I believe this compound will play a more active role in future production and life.

Reference:
Article; Bouz, Ghada; Juhas, Martin; Niklova, Pavlina; Jand?ourek, Ond?ej; Paterova, Pavla; Ek, Ji?i Janou; T?mova, Lenka; Kovalikova, Zuzana; Kastner, Petr; Dole al, Martin; Zitko, Jan; Molecules; vol. 22; 10; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem