Category: 875781-43-4

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. 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, A new synthetic method of this compound is introduced below., 875781-43-4

Step 1. 2-Bromo-5-trityl-5H-pyrrolo[2,3-b]pyrazine. At 40 C., a solution of 2-bromo-5H-pyrrolo[2,3-b]pyrazine (725 mg, 3.66 mmol) and cesium carbonate (3250 mg, 9.95 mmol) in DMF (20.0 mL) was treated with trityl chloride (925 mg, 3.32 mmol). After 2 hours, the reaction mixture was cooled to ambient temperature and poured onto water (150 mL). The mixture was filtered and the filter cake was triturated with water (250 mL) for 1 hour. The solid was isolated and recrystallized from hot ethanol to afford 2-bromo-5-trityl-5H-pyrrolo[2,3-b]pyrazine (750 mg, 52%) as a colorless crystalline solid. LC/MS (M+H) 440.16.

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; Thorarensen, Atli; Brown, Matthew Frank; Casimiro-Garcia, Agustin; Che, Ye; Coe, Jotham Wadsworth; Flanagan, Mark Edward; Gilbert, Adam Matthew; Hayward, Matthew Merrill; Langille, Jonathan David; Montgomery, Justin Ian; Telliez, Jean-Baptiste; Unwalla, Rayomand Jal; US2015/158864; (2015); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

875781-43-4, 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. 875781-43-4 name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, 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.

The compound 2-bromo-5H-pyrrolo [2,3-b] pyrazine (3.00 g, 15.0 mmol) was dissolved in 1,4-dioxane(60 mL), sodium hydroxide solution (2.0 M, 15.0 mL) and formaldehyde solution (37%, 11.4 mL) were added successively, and the mixture was stirred at room temperature night. The reaction solution was concentrated to give a brown oil which was adjusted to pH = 7 with HCl (1.0 M), precipitated with a pale yellow solid, filtered, The filtrate was extracted with EtOAc / MeOH (v / v) = 5/1, 20 mL x 2) and the organic phase was concentrated and the cake was combined and evaporated to dryness to give 4.0 g of yellow Color solid, yield: 99.0%.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, and friends who are interested can also refer to it.

Reference:
Patent; Guangdong East Sunshine Pharmaceutical Co., Ltd; Liu, Bing; Huang, Jiuzhong; Zhang, Yingjun; Xue, Yaping; Xing, Wei; Xu, Juan; Wu, Zuping; Yu, Tianxi; (106 pag.)CN106432246; (2017); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

875781-43-4, These common heterocyclic compound, 875781-43-4, name is 2-Bromo-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.

Step 1 To a partial suspension of 2-bromo-5H-pyrrolo[2,3-b]pyrazine (5.0 g, 25.2 mmol) in 1,4-dioxane (100 mL) was added 2.0 M aqueous NaOH (25 mL, 50.0 mmol) and 37% aqueous formaldehyde (19 mL, 252 mmol). The dark homogenous reaction mixture was stirred at room temperature overnight. The organics were evaporated under reduced pressure. The aqueous layer was neutralized with 1.0 M HCl and extracted with EtOAc (2*). The combined organics were concentrated to afford 2.6 g of an orange solid. Upon standing, a thick brown precipitate formed in the aqueous layer. The precipitate was collected by filtration and dried. The brown solid was extracted with hot 10% MeOH/EtOAC (3*200 mL). The extracts were combined and evaporated to provide an additional 3.05 g of orange solid. Overall yield was 5.65 g (87%) of (2-bromo-7-hydroxymethyl-pyrrolo[2,3-b]pyrazin-5-yl)-methanol.

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 875781-43-4.

Reference:
Patent; Hendricks, Robert Than; Hermann, Johannes; Kondru, Rama; Lou, Yan; Lynch, Stephen M.; Owens, Timothy D.; Soth, Michael; US2011/230462; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

875781-43-4, 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 875781-43-4 as follows.

Step 4: Synthesis of 2-Bromo-7-iodo-5H-pyrrolo[2,3-b]pyrazine.[0285] To a solution of 2-Bromo-5H-pyrrolo[2,3-b]pyrazine (258 mg, 1.3 mmol) inacetone (5 ml) was added Af-iodosuccinimide (324 mg, 1.44 mmol) in one portion. Thereaction mixture was stirred at room temperature for 45 minutes. The resulting precipitatewas filtered off, washed with a minimal amount of acetone, and dried in vacuum to give thetitle compound as a light brown solid ^-NMR (500 MHz, d6-DMSO) ?12.81 (s br, 1H),8.40 (s, 1H), 8.19 (d, 3.0Hz, 1H). MS: m/z 323.8/325.8 [MH+].

According to the analysis of related databases, 875781-43-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; SGX PHARMACEUTICALS, INC.; WO2006/15124; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

875781-43-4, 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. 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, This compound has unique chemical properties. The synthetic route is as follows.

Step 5: Synthesis of 2-Bromo-7-iodo-5-(toluene-4-suIfonyl)-5H-pyrroIo[2,3-b]pyrazine.[0286] To a suspension of 2-Bromo-7-iodo-5H-pyrrolo[2,3-b]pyrazine (290 mg, 0.895mmol) in THF (5 ml) was added NaH (60%, 43 mg, 1.08 mmol) in one portion at 0 C.The resulting mixture was stirred for 20 minutes before a ‘solution of para-toluenesulfonylchloride (188mg, 0.98 mmol) in THF (2 mL) was added. The reaction mixture was thenstirred at room temperature for 3 hours. Solvents were removed and the resulting darkbrown residue washed with aqueous KOH, water and dried to afford the title compound(423 mg, 99% yield) as a light brown solid. .H-NMR (500 MHz, Patent; SGX PHARMACEUTICALS, INC.; WO2006/15124; (2006); A2;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Some common heterocyclic compound, 875781-43-4, name is 2-Bromo-5H-pyrrolo[2,3-b]pyrazine, molecular formula is C6H4BrN3, 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. 875781-43-4

Step 1: 2-Bromo-5H-pyrrolo[2,3-b]pyrazine (1.98 g, 10.0 mmol) was dissolved in DMF (33 mL) and cooled down to 0 C. NaH (60%, 0.480 g, 12.0 mmol) was added slowly. After the addition was complete stirring was continued for 30 minutes at 0 C. (2-Chloromethoxy-ethyl)-trimethyl-silane (2.1 mL, 12.0 mmol) was added and the reaction mixture was allowed to warm up overnight. The reaction was quenched with H2O. The aqueous layer was extracted with EtOAc. The organic layer was dried (MgSO4), filtered, concentrated, and purified by SiO2 chromatography (150 g SiO2, hexanes/EtOAc 0-35% EtOAc) to give 2.81 g of 2-bromo-5-(2-trimethylsilanyl-ethoxymethyl)-5H-pyrrolo[2,3-b]pyrazine as a yellow liquid (86% yield).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 875781-43-4, its application will become more common.

Reference:
Patent; Bamberg, Joe Timothy; Hermann, Johannes Cornellius; Lemoine, Remy; Soth, Michael; US2010/144745; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem