Category: Pyrazines

Related Products of 63744-22-9, A common heterocyclic compound, 63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, molecular formula is C6H3Br2N3, 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 stirred suspension of intermediate example 1 -1 6,8-dibromo-imidazo[1 ,2-a]pyrazine (489 g, 1766 mmol) in MeOH (2900 mL) at -20C was dropwise added a solution of sodium methan thiolate (225 g, 3214 mmol, 1.8 eq) in 800 mL water. After stirring overnight, the clear solution was poured on 30 L water and the yellowish precipitate was filtered, washed with 3 L water and dried in vaccuo to yield 301 g 6-bromo-8-methylsulfanyl-imidazo[1 ,2-a]pyrazine (69.8 %). 1H-NMR (300 MHz, de-DMSO): delta = 8.64 (1 H, s), 8.00 (1 H, d), 7.66 (1 H, d2.54 (3H, s) ppm.

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:
Patent; BAYER PHARMA AKTIENGESELLSCHAFT; SIEMEISTER, Gerhard; BADER, Benjamin; WENGNER, Antje, Margret; MUMBERG, Dominik; KOPPITZ, Marcus; KLAR, Ulrich; KROEMER, Guido; VITALE, Ilio; JEMAA, Mohamed; WO2014/20041; (2014); A1;,
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: 2423-65-6

Conditions: The N-oxide (2 equiv.), aryl halide, Pd(OAc)2 (5 mol %), Pt-Bu3-HBF4 (15 mol %), K2CO3 (2 equiv.) and the additive (if indicated, 2 equiv.) were added to a round bottom flask followed by the addition of dioxane and heating to 110 C.; Initial reaction screens with N-oxides 60, 70 and 80 under previously described conditions lead to disappointing results, probably due to the fact that the N-oxides were only sparingly soluble in toluene. The reaction conditions were reinvestigated. These efforts lead to the discovery that dioxane provides superior conversions with N-oxides 60 and 80 giving the cross coupled products 81 and 82 in 75% and 72% yields respectively (Table 3, entries 1 and 2). These two substrates actually exhibit superior reactivity compared to pyridine N-oxide as demonstrated by a competition experiment between 80 and pyridine N-oxide which results in exclusive arylation of 60 (Table 3, entry 4). In contrast to the excellent results obtained with 60 and 80, pyrimidine N-oxide 70 reacts in low yield (Table 3, entry 3).

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

Application of 889447-19-2, These common heterocyclic compound, 889447-19-2, name is 2-Chloro-5H-pyrrolo[2,3-b]pyrazine, 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.

Example 33A 2-chloro-7-iodo-5H-pyrrolo[2,3-b]pyrazine A 1 M solution of iodine monochloride in dichloromethane (9.84 mL, 9.84 mmol) was added dropwise to an ice-cold solution of 2-chloro-5H-pyrrolo[2,3-b]pyrazine (6.75 g, 11.07 mmol) in anhydrous pyridine (12 mL). The reaction mixture was stirred at 0 C. for 60 minutes, then concentrated. The residue was partitioned between ethyl acetate and brine. The organic phase was washed with brine and concentrated. The crude product was stirred with 15 mL of dichloromethane. The yellow solid material was collected by filtration, washed with dichloromethane and dried to give 2.86 g of the title product. Yield: 66%. MS (DCI+) m/z 280 (M+H)+.

Statistics shows that 2-Chloro-5H-pyrrolo[2,3-b]pyrazine is playing an increasingly important role. we look forward to future research findings about 889447-19-2.

Reference:
Patent; ABBOTT LABORATORIES; US2011/15172; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 19847-12-2,Some common heterocyclic compound, 19847-12-2, name is Pyrazinecarbonitrile, molecular formula is C5H3N3, 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 solution of pyrazine-2-carbonitrile 13 (6.90 g, 65.65 mmol) in toluene (48 mL) and DMF (5 mL) was added sulfuryl chloride (21.2 mL, 260.8 mmol) over 10 min. The reaction mixture was stirred for 30 min in an ice bath, then allowed to warm up to room temperature gradually, after which it was stirred for 5 h. The toluene layer was decanted, and the reddish oil residue was extracted three times with diethyl ether. The combined toluene and ether layers were quenched with ice water and cooled in an ice bath. The combined layers were then neutralized with solid NaHCO3, then separated, and the aqueous layer was extracted with diethyl ether. The combined organic layers were washed with water, dried over anhydrous Na2SO4, filtered, and the solvent was evaporated under reduced pressure to afford the title compound. The crude product was purified by silica gel chromatography (eluent: 100% dichloromethane) to give 3-chloropyrazine-2-carbonitrile 14 as a white powder (4.7 g, 51%). Rf = 0.76 (dichloromethane); mp 44-46 C (lit. [14] : 47-48 C); IR (KBr) numax (cm-1): 3088 (nuCHar), 2242 (nuCN), 1377 (nuC=C), 1087 (nuC-N); 1H NMR (400 MHz, DMSO-d6): delta 8.91 (d, 1H, J = 2.4 Hz, H-6), 8.88 (d, 1H, J = 2.4 Hz, H-5); 13C NMR (100 MHz, DMSO-d6): delta 150.67 (C-3), 147.97 (C-5), 144.26 (C-6), 129.87 (C-2), 114.66 (CN); MS (ESI) m/z (%): 140.3 (100) [M + H]+, 142.3 (40) [M + H + 2]+. Anal. calcd for C5H2ClN3: C, 43.04; H, 1.44; N, 30.11. Found: C, 43.18; H, 1.45; N, 30.16.

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

Reference:
Article; Loidreau, Yvonnick; Marchand, Pascal; Dubouilh-Benard, Carole; Nourrisson, Marie-Renee; Duflos, Muriel; Lozach, Olivier; Loaec, Nadege; Meijer, Laurent; Besson, Thierry; European Journal of Medicinal Chemistry; vol. 58; (2012); p. 171 – 183;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 143591-61-1, These common heterocyclic compound, 143591-61-1, name is 3-Bromo-8-chloroimidazo[1,2-a]pyrazine, 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.

3-Bromo-jV-isopropylimidazor 1 ,2-a1pyrazin-8-amine[00276] A neat mixture of 3-bromo-8-bromo/chloroimidazo[l,2-a]pyrazine (200 mg, 0.86 mmol) and isopropylamine (20 equivalents, 1.48 mL, 17.2 mmol) was stirred at 17O0C for 16hr in a sealed tube. After cooling down, the resulting mixture was partitioned between DCM (150 mL) and water (100 mL). The two layers were separated and the aqueous layer was extracted further with DCM (2 x 50 mL). The combined organic extracts were washed with brine until and dried over anhydrous MgSO4. Evaporation of the solvent afforded crude product (204 mg, 93%). LCMS RT = 1.23 min, MH+ 255.1 & 257.1. 1U NMR (CDCl3): 7.40-7.36 (2H, m), 7.30 (IH, d, J4.8), 5.72 (IH, br s), 4.42-4.22 (IH, br m), 1.27 (3H, s), 1.25 (3H, s).

Statistics shows that 3-Bromo-8-chloroimidazo[1,2-a]pyrazine is playing an increasingly important role. we look forward to future research findings about 143591-61-1.

Reference:
Patent; BioMarin IGA, Ltd.; WREN, Stephen Paul; WYNNE, Graham Michael; LECCI, Cristina; WILSON, Francis Xavier; PRICE, Paul Damien; MIDDLETON, Penny; WO2010/69684; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 957230-70-5, 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. 957230-70-5 name is 3,6-Dibromopyrazin-2-amine, 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.

Step 1: N’-(3,6-Dibromo-pyrazin-2-yl)-N,N-dimethylformamidine (D) A mixture of 3,6-dibromo-pyrazin-2-ylamine (15.37 g, 60.80 mmol) and N,N-dimethylformamide dimethyl acetal (10.1 mL, 76.00 mmol), suspended in ethanol (150 mL), is refluxed for 2 hours. The reaction mixture is evaporated in vacuo affording the title compound. 1H-NMR (400 MHz, CDCl3) delta(ppm) 3.20 (s, 3H), 3.21 (s, 3H), 7.93 (s, 1H), 8.48 (s, 1H). LCMS: Rt 3.81 min (99.1%), m/z (APCI) 307 (M+H)+.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3,6-Dibromopyrazin-2-amine, and friends who are interested can also refer to it.

Reference:
Patent; WIGERINCK, Piet Tom Bert Paul; ANDREWS, Martin James Inglis; De WEER, Marc Maurice Germain; SABOURAULT, Nicholas Luc; KLUGE, Stefan Christian; US2011/118269; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 723286-79-1, A common heterocyclic compound, 723286-79-1, name is tert-Butyl 5,6-dihydro-[1,2,4]triazolo[4,3-a]pyrazine-7(8H)-carboxylate, molecular formula is C10H16N4O2, 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 solution of compound A48-1 (1.29 g, 5.75 mmol) in dry THF (50 mL) was added a solution of 2.5 M n-BuLi in hexane (2.53 mL, 6.33 mmol) at -78 C. under argon. After 15 min ethyl formate (702 muL, 8.63 mmol) was added and the reaction mixture was stirred for 15 min at -78 C. Saturated aqueous NH4Cl (150 mL) was added and the mixture was extracted with CH2Cl2 (3¡Á100 mL). The combined organic layer was dried (Na2SO4) and evaporated to dryness to afford aldehyde A48-2 (1.21 g, 83%).

The synthetic route of 723286-79-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; GRUENENTHAL GmbH; US2009/186899; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 113305-94-5,Some common heterocyclic compound, 113305-94-5, name is 5-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.

A 5 liter flange-neck flask equipped with an air stirrer rod and paddle,thennometer, water condenser and nitrogen bubbler is charged with sodium hydride (22.4 g, 560.1 mmol) and anhydrous THF (3 L). To the well stirred mixture is added 2-amino- 5-cyanopyrazine (67.0 g, 557.8 mmol) portion-wise over 1.5 hours while allowing for any foaming. The internal temperature remains at 22 C throughout. The mixture is stirred for 35 minutes. Then I -(2-methoxy-6-4-methoxy-benzyloxy)-phenyi)-3,3-bis-methyisulfanyl-propenone (146.0 g, 373.9 mmoi) is added at 22 C over one hour. The yellow suspension is stirred for 45 minutes at room temperature and then heating is applied until the reaction is at a gentle refiux. Afier 19 hours at 65 C the reaction mixture is cooled to 15 C. The mixture is then split in two halves and each lot is quenched into water (2 L) and extracted with ethyl acetate (2 x L). The organic extractsare combined and washed with brine, dried over anhydrous Na2SO4, filtered, and concentrated under reduced pressure at 40 C to give the title compound (196 g, 100% crude) as a yellow/orange solid which is used in the next step without further purification. LC-ES/MS mIz 463.2 [M¡ÂHf.

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

Reference:
Patent; ELI LILLY AND COMPANY; STANCATO, Louis Frank; (58 pag.)WO2017/15124; (2017); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 59489-39-3,Some common heterocyclic compound, 59489-39-3, name is 2-Amino-6-cyanopyrazine, 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.

Intermediate 5 (500 mg, 1.13 mmol) , 6-aminopyrazine-2-carbonitrile (163 mg, 1.36 mmol) , palladium (II) acetate (84 mg, 0.374 mmol) , xantphos (215 mg, 0.374 mmol) and cesium carbonate (741 mg, 2.27 mmol) in 1, 4-dioxane (10 mL) under heating at 110 for 1 hour through microwave irradiation under N2 atmosphere. LC-MS: m/z 526.2 (M+H) +.

The synthetic route of 59489-39-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AGIOS PHARMACEUTICALS, INC.; TRAVINS, Jeremy, M.; KONTEATIS, Zenon, D.; SUI, Zhihua; YE, Zhixiong; (199 pag.)WO2018/39972; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 88625-24-5,Some common heterocyclic compound, 88625-24-5, name is 5-Chloropyrazine-2-carbaldehyde, molecular formula is C5H3ClN2O, 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.

tert-Butyl (1R,3r,5S)-3-[5-butylpyrazin-2-yl]oxy-8-azabicyclo[3.2.1]octane-8-carboxylate. Step 1. To a solution of n-propyl-triphenylphosphonium bromide (0.745 g, 1.1 eq., 1.94 mmol) in dry THF (168 mL) n-BuLi (2.5M in hexane) (0.785 mL, 1.1 eq., 1.94 mmol) was added dropwise at 0C. and the reaction mixture was stirred at the same temperature for 45 min. 5-Chloropyrazine-2-carbaldehyde (0.745 g, 1.1 eq., 1.94 mmol) was added and the crude mixture stirred at room temperature for 16 h, quenched with water (20 mL) and extracted with EtOAc (230 mL). The organic extracts were washed with brine, dried over Na2SO4 and concentrated in vacuo to furnish a crude product, which was purified by flash chromatography eluting with cyclohexane/EtOAc (9:1) to give (E/Z)-2-(but-1-enyl)-5-chloro-pyrazine (90 mg, 30%), as a 1:2 cis/trans mixture of isomers.

The synthetic route of 88625-24-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; FONDAZIONE ISTITUTO ITALIANO DI TECNOLOGIA; BERTOZZI, Fabio; BANDIERA, Tiziano; PONTIS, Silvia; REGGIANI, Angelo; GIACOMINA, Francesca; DI FRUSCIA, Paolo; US2019/135778; (2019); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem