Month: May 2021

Reference of 87486-34-8, A common heterocyclic compound, 87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, molecular formula is C5H4Br2N2O, 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: To a solution of 2a-j (10 mmol, 1.0 eq) , 3,5-dibromo-1-methylpyrazin-2(1H)-one (2.95 g, 11 mmol, 1.1 eq) and DIEA (3.3 mL,20 mmol, 2.0 eq) in MeCN (20mL) was stirred at 80 °C for 5 hours. After cooling to room temperature, thesolvent was removed in vacuo, and the residue was purified using silica gelchromatography to give the title compounds, yield 72-85percent.

The synthetic route of 87486-34-8 has been constantly updated, and we look forward to future research findings.

63744-22-9, name is 6,8-Dibromoimidazo[1,2-a]pyrazine, 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: 6,8-Dibromoimidazo[1,2-a]pyrazine

Example 8-1 :Preparation of 6,8-dibromo-3-iodo-imidazo[1 , 2-a]pyrazineTo a stirred solution of intermediate example 1 -1 (8.7 g g, 31 .4 mmol) in DMF (210 mL) was added NiS (7.42 g, 33 mmoi, 1 .05 eq) in one portion at rt. After 18 h stirring at 60 C, the solvent was removed in vaccuo and the residue was taken up in DCM and washed with water and saturated sodium thiosulfate solution. The organic phase was dried over sodium sulphate, filtered and the solvent was evaporated to yield 9.46 g (74.8 %) 6,8-Dibromo-3-iodo-imidazo[1 ,2-a]pyrazine: 1H-NMR (300 MHz, CDCl3): delta = 8.22 (1 H, s), 7.91 (1 H, s) ppm.

The synthetic route of 63744-22-9 has been constantly updated, and we look forward to future research findings.

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. 74290-65-6, name is 3-Bromo-5-methylpyrazin-2-amine, A new synthetic method of this compound is introduced below., category: Pyrazines

Step 2. 3-Bromo-2-ethoxy-5-methylpyrazine. To a solution of 3-bromo-5-methylpyrazin-2-amine (4.00 g, 21.27 mmol) in EtOH (42 mL), at 0 C., was added tert-butyl nitrite (7.65 mL, 63.82 mmol) followed by 4 N hydrochloric acid in 1,4-dioxane (1.91 mL, 7.66 mmol). The reaction mixture was allowed to warm to room temperature and stirred for 8 h. The mixture was concentrated under reduced pressure. The residue was diluted with aq. NaHCO3 and extracted into DCM. The combined organic layers were dried, and the solvent was removed under reduced pressure. Purification (FCC, SiO2, 0-20%, EtOAc/hexanes) afforded the title compound as a white solid (2.5 g, 54%). [M+H]=217.06/219.05.

The synthetic route of 74290-65-6 has been constantly updated, and we look forward to future research findings.

Some common heterocyclic compound, 36070-80-1, name is 5-Chloropyrazine-2-carboxylic acid, molecular formula is C5H3ClN2O2, 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. name: 5-Chloropyrazine-2-carboxylic acid

N,N-Diisopropylethylamine (1.3 mL, 7.5 mmol) was added to a mixture of 5-chloropyrazine-2-carboxylic acid (0.40 g, 2.5 mmol), N,N,N?,N?-tetramethyl-O-(7-azabenzotriazol-1-yl)uronium hexafluorophosphate (1.0 g, 2.8 mmol) and (2S)-1,1,1-trifluoropropan-2-amine (0.28 g, 2.5 mmol) in methylene chloride (10 mL). The reaction mixture was stirred at room temperature overnight. The reaction mixture was worked up with sat. aqueous NaHCO3, and extracted with ethyl acetate. The combined organic layers were washed with brine, dried over MgSO4, filtered and concentrated under reduced pressure. The residue was purified by flash chromatography on a silica gel column with ethyl acetate in hexanes (0-15%) to afford the desired product (0.47 g, 73%). LCMS cacld. for C8H8ClF3N3O (M+1)+: m/z=254.0. Found: 253.9.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 36070-80-1, its application will become more common.

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. 41270-66-0, name is 5-Chloro-2,3-diphenylpyrazine, A new synthetic method of this compound is introduced below., HPLC of Formula: C16H11ClN2

[131] Step 1. 2-(4-((5,6-Diphenylpyrazin-2-yl)(perdeutero-propan-2-yl)amino)butan-l-ol(12c). To a solution of commercially available 5-chloro-2,3-diphenylpyrazine (10) (0.70 g, 2.62 mmol) in NMP (2 mL), was added d7-aminoalcohol lie (0.54 g, 3.93 mmol, 1.5 equiv, prepared as described in Example 7). The reaction vessel was sealed and heated to 190 0C for 15 hours, then cooled to ambient temperature. The mixture was diluted with ice water and extracted with Et2O (3 x 20 rnL). The combined organic layers were washed successively with water and brine. The resulting organic layer was dried (MgSO4), filtered and concentrated in vacuo. The resulting residue was purified by column chromatography (SiO2, 30-50% EtOAc/heptane) to afford 12c (0.20 g, 21%). MS (M+H): 369.2.

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.

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. 21279-62-9, name is 3-Chloropyrazine-2-carboxamide, This compound has unique chemical properties. The synthetic route is as follows., Product Details of 21279-62-9

General procedure: The starting compound (1.27 mmol) was treated with 18 aliphatic amines, alicyclic amines or saturated heterocycles containing at least one nitrogen atom (2.54 mmol). Four reactions were completed by conventional heating methods. The conditions were 110 C, toluene as a solvent and pyridine (1.27 mmol) as a base. The reaction time was set to one hour. Then the reactions were completed using the microwave reactor with focused field and conditions used for syntheses were 140 C, 30 min,120 W, methanol used as a solvent and pyridine (1.27 mmol) as a base. They were set experimentally with respect to prior experience. The progress of reaction was monitored with TLC in system hexane/ethyl acetate (1:1). Then the mixture was separated by flash column chromatograph using gradient elution. Mobile phases were hexane and ethyl acetate again.

According to the analysis of related databases, 21279-62-9, the application of this compound in the production field has become more and more popular.

Related Products of 33332-25-1,Some common heterocyclic compound, 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, molecular formula is C6H5ClN2O2, 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 flask fitted with overhead stirrer, condenser, thermometer and nitrogen line was added methyl 5-chloropyrazine-2-carboxylate (1.0 eq) and tetrahydrofuran (4.92 vols) under a nitrogen atmosphere. The reaction mixture was agitated until all the solid had dissolved, then filtered into a second flask. Water (8.65 vols) was added to the reaction mixture and the mixture agitated for approximately 15 minutes. Potassium carbonate (2.1 eq) was added to the reaction mixture and the mixture agitated for 16 hours at 20-25 C. Then 32% w/w hydrochloric acid (3.76 eq) was added over 3 hours in small portions, keeping the reaction temperature 20-25 C., to a pH end point of pH2.2. The resultant slurry was heated to approximately 35-40 C. and then distilled under vacuum at this temperature distilling approximately 5.3 vols, to a final volume of approximately 9.3 vols. The mixture was then cooled to 20-25 C. over at least 2 hours, agitated for 10 hours at this temperature and then filtered. The solid was washed with water (2.8 vols), and the wet product produced dried at 35 C. in a vacuum oven. The desired product was obtained as a solid (corrected yield 91%) 1H NMR delta (400 MHz CDCl3): 7.20 (1H, bs), 8.72 (1H, s), 9.21-9.21 (1H, m); m/z 157 (M-H)+.

The synthetic route of 33332-25-1 has been constantly updated, and we look forward to future research findings.

Adding a certain compound to certain chemical reactions, such as: 33332-28-4, name is 2-Amino-6-chloropyrazine, 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 33332-28-4, category: Pyrazines

(c) N-(6-Chloro-pyrazin-2-yl)-4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide This compound was prepared from benzyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide and 2-amino-6-chloro-pyrazine analogous to Example 1. Yield: 49percent of theory. Melting point: 278°-279° C. (decomposition). C14 H11 ClN4 O4 S (366.79): Calc.: C–45.84percent; H–3.03percent; Cl–9.67percent; N–15.28percent; S–8.74percent. Found: C–46.10percent; H–3.16percent; Cl–9.78percent; N–15.01percent; S–8.56percent.

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.

Synthetic Route of 762240-92-6, 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 762240-92-6 as follows.

7-[(3R)-3-[N-(tert-butoxycarbonyl)amino]-4-(2,4,5-trifluorophenyl)butanoyl]-3-(trifluoro-methyl)-5,6,7,8-tetrahydro-1,2,4-triazolo[4,3-a]pyrazine (12)To a solution of 3-trifluoromethyl-5,6,7,8-tetrahydro[1,2,4]triazolo[4,3-a]pyrazine hydrochloride (11) (1.0 eq, 28.0 gm), diisopropylethylamine (2.0 eq, 31.0 gm), 1-hydroxybenzotriazole (1.2 eq, 22.0 gm), and EDC-HCl (1.2 eq, 28.0 gm) in N,N-dimethylformamide (4.0 vol, 160.0 ml), a solution of (3R)-3-[N-(tert-butoxycarbonyl)amino]-4-(2,4,5-trifluorophenyl)butanoic acid (07) (40.0 gm, 0.12 mol) in N,N-dimethylformamide (4.0 vol, 160.0 ml) was charged at 0-5 C. within 1 hour. The clear pale yellow solution was further stirred for 12 hours at 25-30 C. After stirring for 12 hours, the N,N-dimethylformamide was distilled out completely at 55-65 C. under reduced pressure to give a brown coloured residue. The brown coloured residue was further basified with 10% Na2CO3 solution (1.0 vol, 40.0 ml) and the product was extracted in ethyl acetate (3×10.0 vol, 3×400.0 ml). The combined ethyl acetate layers were washed with water, charcoalized and filtered, and the ethyl acetate was distilled out completely to give a white coloured product. The product was triturated with hexane (10.0 vol, 400.0 ml) and filtered at 25-30 C. The crude Boc-protected sitagliptin free base (12) was further purified by crystallising it from a mixture of isopropanol (20.0 vol) and water (2.0 vol).Molar Yield: 75-81% (56 gm)Chemical Purity: 95-97% (as measured by HPLC)

According to the analysis of related databases, 762240-92-6, the application of this compound in the production field has become more and more popular.

Related Products of 109-08-0, A common heterocyclic compound, 109-08-0, name is 2-Methylpyrazine, molecular formula is C5H6N2, 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.

In a 500 mL reactor, 94.1 g (1 mol) of 2-methylpyrazine was added.0.2 g (0.0016 mol) of ferrous chloride, and 225 g (1.99 mol) of hydrogen peroxide having a mass concentration of 30percent was added dropwise at 30 ° C.After the completion of the dropwise addition for 4 hours, the temperature was raised to 50 ° C, and 40 g (2.35 mol) of ammonia gas was introduced. After the completion of the ammonia gas, the temperature was maintained for 7 hours.After cooling to 10 ° C, the crude product was filtered.The crude product was recrystallized from 3 times by weight of water to give 117 g of the desired pyrazinamide in a yield of 95percent.

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.