Tag: M.W=100-200

Synthetic Route of 33332-28-4, 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. 33332-28-4 name is 2-Amino-6-chloropyrazine, 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.

EXAMPLE 7 N-(6-Chloro-pyrazin-2-yl)-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide A mixture of 5.1 g (20 mmols) of methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide, 3.0 g (23 mmols) of 2-amino-6-chloropyrazine and 400 ml of xylene was refluxed for 12 hours in a nitrogen atmosphere. The methanol formed by the reaction was removed with the aid of a 4 A molecular sieve arranged in a Soxhlet attachment. After cooling, the reaction mixture was concentrated by evaporation, and the residue was purified by chromatography on a silicagel column, yielding 2.3 g (33percent of theory) of N-(6-chloro-pyrazin-2-yl)-4-hydroxy-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide. Melting point: 234¡ã-235¡ã C. (from ethanol). C13 H9 ClN4 O4 S (352.76): Calc.: C–44.26percent; H–2.57percent; N–15.88percent; Cl–10.05percent; S–9.09percent. Found: C–44.02percent; H–2.65percent; N–15.92percent; Cl–10.10percent; S–9.24percent.

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

Reference:
Patent; Dr. Karl Thomae Gesellschaft mit beschrankter Haftung; US4533664; (1985); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route 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.

A solution of 5.4 g (40 mmol) 1-Pyrazin-2yl-ethanone in 21 ml HBr (33%) and 7 ml methanol was treated with 2.05 ml (40 mmol) bromine and heated to 60 C. for 7 h.The precipitate was filtered off, washed with ethyl acetate/diethyl ether 1/1 and dried to obtain 8.3 g (55%) of the title compound as grey solid. 1-H-NMR (400 MHz, DMSO-d6) delta=8.78 (d, J=2 Hz, 1H, H-5), 8.66 ((d, J=2 Hz, 1H, H-6), 5.01 (s, 2H, CH2), 2.75 (s, 3H, CH3). MS (m/e): 215.0 (M+H, 100%).

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:
Patent; Mattei, Patrizio; Neidhart, Werner; Nettekoven, Matthias Heinrich; Pflieger, Philippe; Taylor, Sven; US2003/225141; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 4744-50-7, 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.

a 3-(m-methylbenzoyl)-pyrazine-2-carboxylic acid The Grignard reagent from 8.5 g (50 mmol) 3-bromotoluene and 1.2 g magnesium in 50 ml ether was added dropwise at 0-10 C. to a solution of 7.5 g (50 mmol) pyrazine-2,3-dicarboxylic acid anhydride in 100 ml THF and after completed addition, the solution that formed was stirred for 4 hours at room temperature. 500 ml cold, saturated NH4 Cl solution was then added, it was extracted with ethyl acetate and the organic phase was dried, concentrated by evaporation and purified as in example 1a and 2a. Yield 4 g (32% of theoretical yield).

Statistics shows that 2,3-Pyrazinecarboxylic anhydride is playing an increasingly important role. we look forward to future research findings about 4744-50-7.

Reference:
Patent; Boehringer Mannheim GmbH; US5512564; (1996); A;,
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. 77112-52-8, name is Ethyl imidazo[1,2-a]pyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., COA of Formula: C9H9N3O2

[0079] Method A-Step b: Preparation of 7-tert-butyl-2-ethyl-5,6-dihydroimidazo[l,2- a]pyrazine-2 -dicarboxylate [0080] To a solution of ethyl imidazo[l,2-a]pyrazine-2-carboxylate (1 g, 5.2 mmol) in 500 mL ethyl alcohol was added Boc20 (3.0 g, 18 mmol) and 200 mg 10% Pd-C (50% wet) under hydrogen atmosphere, then the mixture was stirred at room temperature for 24 hours. The reaction mixture was filtered, the filtrate was concentrated under reduced pressure. The residue was applied to silica gel column chromatography and eluted with (CH2Cl2:MeOH = 50:1). The title compound was obtained as a yellow oil (0.973 g, 63%). *H NMR (400 MHz, CDCI3) delta 7.51(s, 1H), 4.68 (s, 2H), 4.30 (q, 7 = 7.1 Hz, 2H), 4.00 (t, 7 = 5.2 Hz, 2H), 3.82 (t, 7 = 5.2 Hz, 2H), 1.43 (s, 9H), 1.21 (t, 7 = 7.1 Hz, 3H).

The synthetic route of 77112-52-8 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; ZHANG, Xiaohu; WO2014/113191; (2014); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Electric Literature of 4744-50-7, A common heterocyclic compound, 4744-50-7, name is 2,3-Pyrazinecarboxylic anhydride, molecular formula is C6H2N2O3, 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.

General procedure: Pyrazine-2,3-dicarboxylic anhydride (1.0 g, 6.7 mmol) was dissolved in tetrahydrofuran (40 mL)in an Erlenmeyer flask and the corresponding substituted aniline (6.7 mmol, 1 equiv.) was added in one dose. The reaction mixture was stirred for 1 hour at laboratory temperature. Water (30 mL) was added into the mixture followed by the saturated aqueous solution of NaHCO3 until pH 6 to form thecorresponding 3-(phenylcarbamoyl)pyrazine-2-carboxylic acid 1-18. Obtained crystals were filtered off and washed with water. The progress of the procedure was monitored by TLC eluted with thesystem water/butanol/acetic acid 5:4:1.

The synthetic route of 4744-50-7 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Semelkova, Lucia; Jano?cova, Petra; Fernandes, Carlos; Bouz, Ghada; Jand?Ourek, Ond?ej; Kone?na, Klara; Paterova, Pavla; Navratilova, Lucie; Kune?, Ji?i; Dole?al, Martin; Zitko, Jan; Molecules; vol. 22; 9; (2017);,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 56423-63-3, The chemical industry reduces the impact on the environment during synthesis 56423-63-3, name is 2-Bromopyrazine, I believe this compound will play a more active role in future production and life.

Methyl 4-(2-pyrazinyl) benzoate (0432) In a 250-mL round-bottom flask purged and maintained with an inert atmosphere of nitrogen were combined a solution of [4-(methoxycarbonyl)phenyl]boronic acid (1 g, 5.56 mmol, 1.20 equiv) in 1,4-dioxane (30 mL), 2-bromopyrazine (800 mg, 5.03 mmol, 1.00 equiv), a solution of Na2CO3 (1.5 g, 14.15 mmol, 3.00 equiv) in water (30 mL), and Pd(Ph3P)2Cl2 (330 mg, 0.47 mmol, 0.10 equiv). The resulting solution was stirred for 16 h at 90 C. in an oil bath. The solids were filtered out. The resulting solution was extracted with 3¡Á30 mL of EtOAc, and the organic layers combined and concentrated under vacuum. This resulted in 0.8 g (74%) of the product as a white solid.

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

Reference:
Patent; Imago Biosciences, Inc.; Rienhoff, JR., Hugh Y.; McCall, John M.; Clare, Michael; Celatka, Cassandra; Tapper, Amy E.; (226 pag.)US2016/237043; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 91476-80-1, These common heterocyclic compound, 91476-80-1, name is 5,6,7,8-Tetrahydroimidazo[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.

C-1 a (50 mg; 0.16 mmol) is dissolved in dioxane. 5,6,7,8-tetrahydro-imidazo[1 ,2- a]pyrazine E-1a (19 mg; 0.16 mmol), sodium ie f-butoxide (40 mg; 0.42 mmol) and chloro(2-dicyclohexylphosphino-2′,4′,6′-tri-isopropyl-1 ,1 ‘-biphenyl)[2-(2-aminoethyl)phenyl] palladium(ll) methyl-i-butyl ether adduct (9 mg; 0.01 mmol) are added and the reaction mixture is stirred at 75 C for 2 h. The solvents are evaporated under reduced pressure and the crude material is purified using reversed phase chromatography (method: prep. HPLC1 ) to afford I-029. Yield: 48 % (27 mg; 0.08 mmol) HPLC-MS: (M+H)+ = 362; tRet = 0.96 min; method LCMSBAS1

The synthetic route of 91476-80-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; BOEHRINGER INGELHEIM INTERNATIONAL GMBH; ENGELHARDT, Harald; ARNHOF, Heribert; CAROTTA, Sebastian; HOFMANN, Marco; KERENYI, Marc; SCHARN, Dirk; (118 pag.)WO2019/68613; (2019); 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. 17231-51-5, name is 3-Amino-6-bromopyrazine-2-carbonitrile, A new synthetic method of this compound is introduced below., SDS of cas: 17231-51-5

REFERENTIAL EXAMPLE II-9 In 10 mL of tetrahydrofuran was dissolved 0.50 g of 3-amino-6-bromo-2-pyrazinecarbonitrile. After adding 0.15 g of 60% sodium hydride, the mixture was stirred at room temperature for 15 minutes. Then, 0.7 mL of di-t-butyl dicarbonate and 0.10 g of 60% sodium hydride were successively added, and the mixture thus formed was stirred at room temperature for one hour. The reaction mixture was added to a liquid mixture consisting of 30 mL of ethyl acetate and 60 mL of water, pH was adjusted to 5 with 2 mol/L hydrochloric acid, and the organic layer was separated. The organic layer was washed successively with water and saturated aqueous solution of sodium chloride and dried on anhydrous magnesium sulfate, and the solvent was removed under reduced pressure. The residue thus obtained was purified by silica gel column chromatography [eluent: n-hexane:ethyl acetate=5:1] to obtain 0.30 g of t-butyl 5-bromo-3-cyano-2-pyrazinylcarbamate as a white-colored solid product. IR(KBr) cm-1: 2239, 1708 1H-NMR (CDCl3+DMSO-d6) delta: 1.57(9H,s), 7.41(1H,brs), 8.62(1 H,s)

The synthetic route of 17231-51-5 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Toyama Chemical Co., Ltd.; US2003/130213; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Application of 6863-73-6, 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 6863-73-6 as follows.

alpha-Bromo diethyl acetal (51.6 mL, 332.7 mmol, 2.5 eq) was added to a solution of 7.7 mL HBr (conc.) and 80 mL of H2O. The reaction was heated at reflux for 1 h. The reaction was cooled and extracted 2¡Á with Et2O (200 mL). The Et2O extracts were combined, washed with brine, and dried over Na2SO4 before being concentrated. The material was not left on the rotavap for an extended time or put under high vacuum. The oily residue was mixed with DME (200 mL) and the 2-amino-3-chloropyrazine (2, 17.240 g, 133.1 mmol) was added. HBr conc. (1-1.5 mL) was added and the reaction was heated at reflux. The reaction is heterogeneous reaction mixture, becomes homogenous after 10-15 minutes. After approximately 30 minutes a precipitate begins to form. After 1 hour at reflux the black reaction was cooled to room temperature, filtered, and washed with Et2O (4¡Á, 75 mL) to give compound 101 1H NMR (DMSO-d6, 400 MHz) 8.70 (d, J=2.0 Hz, 1H), 8.32 (s, 1H), 7.93 (s, 1H), 7.79 (d, J=3.0 Hz, 1H). LC/MS shows a mixture of two products (one product by LC and two by MS). By MS there is a mass for XCl (major) MH+=154 (m/z) and one for XBr (minor) MH+ 198 (m/z). This mixture gave the product in approximately 90% yield as the HBr salt.

According to the analysis of related databases, 6863-73-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Schering Corporation; US2007/105864; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Related Products of 6164-79-0, These common heterocyclic compound, 6164-79-0, name is Methyl 2-pyrazinecarboxylate, 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.

Methyl pyrazine-2-carboxylate (0.5g; 3.6mmol) was dissolved in THF (5mL), and 98% hydrazine (0.53mL; 11mmol) was added. The mixture was refluxed for 3h and cooled to rt. The resulting solid was filtered off, washed with THF and dried over P2O5 to give 0.28g (56%) of a white solid. Rf=0.53 (CHCl3/MeOH 10:1). mp 166-169C (lit. 167-169C) [64]. 1H NMR (300MHz, DMSO): delta 10.11 (s, 1H, NH), 9.12 (s, 1H, Ar), 8.82 (d, J=2.4Hz, 1H, Ar), 8.68 (d, J=2.4Hz, 1H, Ar), 4.65 (s, 2H, NH2). 13C NMR (75MHz, DMSO): delta 161.7, 147.4, 145.1, 143.7, 143.4.

The synthetic route of 6164-79-0 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Hru?kova, Kate?ina; Pot??kova, Eli?ka; Hergeselova, Tereza; Liptakova, Lucie; Ha?kova, Pavlina; Mingas, Panagiotis; Kova?ikova, Petra; ?im?nek, Toma?; Vavrova, Kate?ina; European Journal of Medicinal Chemistry; vol. 120; (2016); p. 97 – 110;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem