Month: March 2021

Application of 55557-52-3,Some common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, molecular formula is C5H2ClN3, 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.

EXAMPLE 8A 3-chloro-2-cyanopyrazine-1-oxide 2-Chloro-3-cyanopyrazine (5.00 g, 35.94 mmol) in concentrated H2SO4 (35 mL) at 0 C. was treated portionwise with K2S2O8 (11.65 g, 43.95 mmol), warmed to room temperature, stirred for 24 hours, treated with water, and extracted with chloroform. The organic extract was washed sequentially with water, saturated NaHCO3 and brine, dried (MgSO4) and concentrated to provide the title compound. MS (DCI/NH3) m/e 173 (M+NH4)+.

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

Reference:
Patent; Abbott Laboratories; US6376488; (2002); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 193966-70-0, name is Methyl 5-(bromomethyl)pyrazine-2-carboxylate, molecular formula is C7H7BrN2O2, 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. category: Pyrazines

Example 13-3 Synthesis of 5-(N-Boc-N-2-picolylaminomethyl)pyrazine-2-carboxylic acid (Compound VII-6) The compound obtained in Example 13-2 (320 mg) was dissolved in DMF (6.4 ml) and potassium carbonate (383 mg) and 2-picolylamine (286 mul) were added. After the reaction for 17 hours, the reaction solution was concentrated, and added with water, followed by extraction with chloroform. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated to obtain a crude product of the title compound (444.1 mg) as brown syrup. The crude product was dissolved in dioxane (4 ml),and di-t-butyldicarbonate (0.35 ml) and 1 mol/l aqueous solution.of sodium hydroxide (4 ml) were added. After the reaction for 2 hours, the reaction solution was concentrated. After the addition of dilute hydrochloric acid, the residue was extracted with chloroform. The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated to obtain the title compound (158.8 mg) as a light brown solid. MS(FAB,Pos.):m/z=345[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 193966-70-0, its application will become more common.

Reference:
Patent; Kureha Chemical Industry Co., Ltd.; EP1273571; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 32493-79-1,Some common heterocyclic compound, 32493-79-1, name is 2,3-Dichloro-5,6-dimethylpyrazine, molecular formula is C6H6Cl2N2, 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.

Scheme 3, step 1 : A stirred solution of 2,3-dichloro-5,6-dimethylpyrazine (2.0 g, 11.298 mmol) and hydrazine (0.943 mL, 28.2 mmol, 95 mass%) in EtOH (15 mL) is heated at 100 C overnight. The reaction mixture is concentrated under reduced pressure to give the title compound (1.94 g, 84.6%). MS (m/z) 173 (M+H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2,3-Dichloro-5,6-dimethylpyrazine, its application will become more common.

Reference:
Patent; ELI LILLY AND COMPANY; CAMP, Nicholas Paul; HAMDOUCHI, Chafiq; LINESWALA, Jayana Pankaj; MORPHY, John Richard; SHI, Qing; (41 pag.)WO2019/156861; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 41110-28-5,Some common heterocyclic compound, 41110-28-5, name is 3-Methylpyrazine-2-carboxylic acid, molecular formula is C6H6N2O2, 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: Methyl 3-methylpyrazine-2-carboxylate In a 2-L flask, 3-methylpyrazine-2-carboxylic acid (Matrix, 19.95 g, 144 mmol) was suspended in MeOH (500 mL). The suspension was cooled in an ice-water bath, and concentrated sulfuric acid (Fluka, 27.3 mL, 506 mmol) was added over a time period of 5 min. The reaction mixture was heated to 80 C. for 5 h. The reaction mixture was concentrated under reduced pressure and the residue was taken up in DCM (750 mL). The excess acid was neutralized carefully with aqueous NaOH (5m, 200 mL). The aqueous layer was separated and extracted with DCM (250 mL). The combined organic layers were combined, dried over MgSO4 and concentrated to afford 16.15 g of the title compound (106 mmol, 73%). MS m/z=153 [M+H]+. Calculated for C7H8N2O2: 152.

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

Reference:
Patent; MINATTI, Ana Elena; LOW, Jonathan D.; ALLEN, Jennifer R.; CHEN, Jian; CHEN, Ning; CHENG, Yuan; JUDD, Ted; LIU, Qingyian; LOPEZ, Patricia; QIAN, Wenyuan; RUMFELT, Shannon; RZASA, Robert M.; TAMAYO, Nuria A.; XUE, Qiufen; YANG, Bryant; ZHONG, Wenge; US2014/249104; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

These common heterocyclic compound, 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, 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. category: Pyrazines

General procedure: A mixture of 4-(2-aminoethyl)benzenesulfonamide (0.5 g,2.5 mmol), anhydrous sodium acetate (0.41 g, 5.0 mmol) and anacid anhydride (2.5 mmol) was stirred in glacial acetic acid(15 mL). The mixture was heated under reflux for 12 h and thereaction was monitored with the help of TLC. After completion ofreaction the solvent was removed under reduced pressure andthe crude solid obtained was washed with water, dried and recrystallisedfrom an appropriate solvent.

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

Reference:
Article; Abdel-Aziz, Alaa A.-M.; Angeli, Andrea; El-Azab, Adel S.; Abu El-Enin, Mohamed A.; Supuran, Claudiu T.; Bioorganic and Medicinal Chemistry; vol. 25; 5; (2017); p. 1666 – 1671;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 2423-65-6, name is Pyrazine 1-oxide, A new synthetic method of this compound is introduced below., Recommanded Product: Pyrazine 1-oxide

General Procedure 2:; Palladium-Catalyzed Direct Arylation with Aryl Chlorides and Bromides.; To a dried flask was added the diazine N-oxide (1.0 to 3.0 equiv.), K2CO3 (2.0 equiv.), Pd(OAc)2 (5 mol %) and HP(t-Bu)3BF4 (15 mol %). If the arylhalide is a solid, it is added at this point (1.0 equiv.). The flask and its contents were then purged under nitrogen for 10 minutes. If the aryl halide is a liquid, it is added via syringe after purging, followed by the addition of degassed dioxane (to produce a reaction concentration of 0.3 M relative to the halide). The reaction mixture was then heated at 110 C. until the reaction was complete, after which the volatiles were removed under reduced pressure and the residue was purified via silica gel column chromatography.2-(3-Methoxyphenyl)pyrazine N-oxide (Table 4, Entries 6 and 7) Synthesised according to general procedure 2. Purification via silica gel column chromatography using 100% DCM then a mixture of 15% Acetone/DCM gave a white solid, 72% with 2 eq. of the N-oxide and 84% yield with 3 eq. of the N-oxide). 1H NMR (300 MHz, CDCl3, 293K, TMS): delta 8.63 (1H, s), 8.38 (1H, d, J=3.9 Hz), 8.20 (1H, d, J=4.2 Hz), 7.46-7.29 (3H, m), 7.05 (1H, dd, J=1.8 and 8.4 Hz), 3.85 (3H, s). 13C NMR (75 MHz, CDCl3, 293K, TMS): 159.4, 148.3, 145.5, 144.3, 134.4, 130.0, 129.6, 121.3, 116.2, 114.4, 55.3.

The synthetic route of 2423-65-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; University of Ottawa; US2008/132698; (2008); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

14508-49-7, name is 2-Chloropyrazine, 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. Recommanded Product: 14508-49-7

[0410] Step A: [0411] 1M aq. Na2CO3 (20 mL) and ethanol (10 mL) were added to a solution of 2-chloropyrazine (2.30 g, 20.06 mmol), 4-formylphenylboronic acid (3.90 g, 26.01 mmol) and [1,4-bis(diphenylphosphino)butane]palladium(II) dichloride (0.60 g, 0.99 mmol) in toluene (40 mL) and the mixture was heated to reflux for 18 h. The cooled reaction mixture was diluted with ethyl acetate, washed with sat. aq. NaHCO3 and brine, dried (MgSO4), and concentrated. Purification by chromatography (SiO2, 4:1 hexane/ethyl acetate) yielded 1.56 g (42%) of 4-pyrazinylbenzaldehyde.

The synthetic route of 14508-49-7 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Henninger, Todd C.; Macielag, Mark J.; Marinelli, Brett A.; Zhu, Bin; US2004/18994; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 22047-25-2, The chemical industry reduces the impact on the environment during synthesis 22047-25-2, name is Acetylpyrazine, I believe this compound will play a more active role in future production and life.

General procedure: Previous method was applied to prepare Ligands (L1-L3). Piperidylthiosemicarbazide was dissolved in ethanol solution (10mL, 1mM), stirring, Corresponding aldehydes or ketones (One mole equivalent) and 5 drops of acetic acid glacial were added to it and refluxed for 4h. Filter paper was used for conquering precipitate. Rinsed the precipitate with ice-cold ethanol and dried it in a vacuum desiccator.

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

Reference:
Article; Qi, Jinxu; Yao, Qian; Tian, Liang; Wang, Yihong; European Journal of Medicinal Chemistry; vol. 158; (2018); p. 853 – 862;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 1209646-17-2, These common heterocyclic compound, 1209646-17-2, name is 5-(4-(tert-Butoxycarbonyl)piperazin-1-yl)pyrazine-2-carboxylic acid, 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 suspension of 1-77 (1.0 g, 3.53 mmol) in THF (20 ml) is added 1,1′- carbonyldiimidazole (0.63 g, 3.88 mmol) at room temperature. The mixture is stirred at 50 C for 30 minutes. After this time 1-19 (1.2 g, 3.88 mmol) is added as a THF solution (15 ml) and the resulting mixture is heated at 80C for 3 hours. The mixture is cooled and treated with AcOH (8 ml) then warmed to 80C and stirred over night. After this time the reaction is cooled to room temperature, concentrated and diluted with water.Extracted the product into DCM (2x). The combined organics are washed with brine and dried (MgS04). Filtered and concentrated. The remaining crude is purified via flash chromatography (silica gel, 0-5% MeOH/DCM) to afford 1-84 (1.2 g).

Statistics shows that 5-(4-(tert-Butoxycarbonyl)piperazin-1-yl)pyrazine-2-carboxylic acid is playing an increasingly important role. we look forward to future research findings about 1209646-17-2.

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; BARTOLOZZI, Alessandra; BOSANAC, Todd; CHEN, Zhidong; DE LOMBAERT, Stephane; HUBER, John; LO, Ho Yin; LOKE, Pui Leng; LIU, Weimin; MORWICK, Tina Marie; OLAGUE, Alan; RIETHER, Doris; TYE, Heather; WU, Lifen; ZINDELL, Renee; WO2012/24150; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 13535-07-4, 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. 13535-07-4 name is 2-Amino-5-ethylpyrazine, 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.

Pyridine (1.051 mL, 12.99 mmol) was added dropwise to a stirred solution of phenyl carbonochloridate (1.324 mL, 10.56 mmol) in dichloromethane (DCM) (20 ml) at room temperature and stirred for 30 minutes. Then 5-ethylpyrazin-2-amine (1 g, 8.12 mmol) dissolved in dichloromethane (DCM) (10 ml) was added dropwise at room temperature and stirred at 50 C. for 16 h. Allowed the reaction mixture to room temperature, diluted with DCM (3¡Á50 mL), washed with water (2¡Á30 mL) and brine (30 mL). Separated the organic layer and dried over sodium sulfate, filtered and concentrated. Residue was purified by column chromatography using silica gel (100-200 mesh) by 10% ethyl acetate in pet ether as eluent to get desired product as off white fluffy solid (1.6 g, 6.58 mmol, 81%), LCMS (m/z) 244.2 (M+H)+.

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

Reference:
Patent; BLUM, Charles A.; Caldwell, Richard Dana; Casaubon, Rebecca; Disch, Jeremy S.; Fox, Ryan Michael; Koppetsch, Karsten; Miller, William Henry; NG, Pui Yee; Oalmann, Christopher; Perni, Robert B.; Szczepankiewicz, Bruce G.; White, Brian; US2015/152108; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem