Tag: M.W=100-200

Electric Literature of 95-89-6, These common heterocyclic compound, 95-89-6, name is 3-Chloro-2,5-dimethylpyrazine, 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. 3,6-Dimethylpyrazin-2-amine A 100 mL autoclave vessel was charged with 3-chloro-2,5-dimethylpyrazine (25.0 g, 176 mmol), NH3 (aq. 25-28% w/w, 80 mL) and Cu powder (1.69 g, 26.4 mmol) and the autoclave vessel was sealed. The resulting mixture was heated to 150 C. and stirred vigorously for 48 h. The reaction mixture was cooled to room temperature and concentrated under reduced pressure. The residue was diluted with brine (100 mL) and extracted with EtOAc (4*100 mL). The combined extracts were dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was washed with PE to render the title compound as a light yellow solid (17.6 g, yield 81%). ESI MS: m/z 124 [M+H]+.

The synthetic route of 95-89-6 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Sunovion Pharmaceuticals Inc.; US2012/178748; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Reference of 19847-12-2, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 19847-12-2, name is Pyrazinecarbonitrile belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

General procedure: 2-Cyanopyridine (0.420 ml; 4 mmol) was dissolved in absolute methanol (20 ml) and to it was added sodium methoxide solution in methanol (1.0 ml) (previously prepared). The reaction contents were stirred at room temperature for 2 h 1,4-diaminobutane (0.18 ml, 2 mmol) was added to the reaction mixture. Reaction contents were heated under reflux for 12 h. Solvent was removed under reduced pressure. Crude product so obtained was washed with diethyl ether and then with ethyl acetate to give thick mass. Solvent traces from this thick mass was removed by applying high vacuum for 15 min to give semisolid product i.e. N-(2-pyridineimidoylamino-butyl)-pyridine-2-carboxamidine (5a). Yield 480 mg (81%).

The synthetic route of Pyrazinecarbonitrile has been constantly updated, and we look forward to future research findings.

Reference:
Article; Arya, Surbhi; Kumar, Nikhil; Roy, Partha; Sondhi; European Journal of Medicinal Chemistry; vol. 59; (2013); p. 7 – 14;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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, COA of Formula: C4H4ClN3

EXAMPLE 11 N-(6-Chloro-pyrazin-2-yl)-4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxamide-1,1-dioxide This compound was prepared from ethyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate-1,1-dioxide and 2-amino-6-chloro-pyrazine analogous to Example 1. Yield: 60percent of theory. Melting point: 278-279¡ã 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–45.91percent; H–3.09percent; Cl–9.60percent; N–15.00percent; S–8.78percent.

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-Amino-6-chloropyrazine, other downstream synthetic routes, hurry up and to see.

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

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 14508-49-7 as follows. COA of Formula: C4H3ClN2

An oven dried resealable Schlenk tube was charged with 2′-(4-methylpiperazin-1-yl)-2,4′-bipyridin-6-amine (example 34a, 0.09 g, 0.33 mmol), 2-Chloropyrazine (0.04 muL, 0.39 mmol), sodium tert-butoxide (0.04 g, 0.38 mmol) and dioxane (1 mL). The Schlenk tube was subjected to three cycles of evacuation-backfilling with argon, and tris(dibenzylideneacetone)dipalladium(0) (0.01 g, catalytic amount) and 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (0.01 g, catalytic amount) were added. After three further cycles of evacuation-backfilling with argon, the Schlenk tube was capped and placed in an oil bath at 95 C. After 16h, the mixture was cooled and the solvent was removed in vacuo. The residue was purified by flash chromatography to give the title compound (0.09 g, 82%) as a solid.LRMS (m/z): 348 (M+1)+.1 H NMR (500 MHz, CHLOROFORM-d) delta ppm 2.35 (s, 3 H) 2.53 – 2.55 (m, 4 H) 3.63 – 3.66 (m, 4 H) 7.16 (dd, J=6.50, 2 Hz, 1 H) 7.34 (s, 1 H) 7.39 (d, J=9.00 Hz, 1 H) 7.61 (d, J=10.00 Hz, 1 H) 7.73 (t, J=10.00 Hz, 1 H) 7.96 (br. s., 1 H) 8.13 (d, J=3.50 Hz, 1 H) 8.19 – 8.21 (m, 1 H) 8.13 (d, J=3.50 Hz, 1 H) 8.98 (d, J=2.00 Hz, 1 H)

According to the analysis of related databases, 14508-49-7, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Almirall, S.A.; Vidal Juan, Bernat; Forns Berenguel, Maria Pilar; Castillo Mcquade, Marcos; Erra Sola, Montserrat; Mir Cepeda, Marta; EP2441755; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 59489-71-3,Some common heterocyclic compound, 59489-71-3, name is 2-Amino-5-bromopyrazine, molecular formula is C4H4BrN3, 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 2; 5-bromopyrazine-2-carbonitrile; i) Tetrakis (triphenyl phosphine) palladium(0) (10 mg) was added to a mixture of 5-bromopyrazin-2-amine (0.575 mmol), potassium cyanide (1.15 mmol), copper (I) iodide (0.575 mmol) and 18-crown-6 (20 mg) in dry DMF (1 mL) in a screw top reaction vessel under nitrogen atmosphere, and the mixture was heated with stirring at 200 C. for 1 h. After cooling, water (5 mL) was added and the product was extracted with chloroform (2¡Á) to give 5-aminopyrazine-2-carbonitrile after purification by chromatography (silica, hexane:ethyl acetate) (0.208 mmol, 36%).

The synthetic route of 59489-71-3 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; AstraZeneca AB; NPS PHARMACEUTICALS, INC.; US2007/37820; (2007); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

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. 16298-03-6, name is Methyl 2-aminopyrazine-3-carboxylate, This compound has unique chemical properties. The synthetic route is as follows., category: Pyrazines

EXAMPLE 157A Methyl 3-bromopyrazine-2-carboxylate To a rapidly stirring heterogeneous mixture of 3-aminopyrazine-2-carboxylic acid methyl ester (2.00 g, 13.1 mmol) in 48percent hydrobromic acid (7.9 mL) cooled to 0¡ã C. was added bromine (2.00 mL, 6.2 g, 38.8 mmol) dropwise over 5 minutes. Then a solution of sodium nitrite (2.27 g, 32.8 mmol) in 9.5 mL of water was added dropwise over 10 minutes. The reaction mixture was stirred at 0¡ã C. for 15-30 minutes and then basified with 60 mL of saturated sodium bicarbonate solution and extracted with ethyl acetate followed by chloroform. The combined organic extracts were dried over magnesium sulfate and concentrated under reduced pressure. The residue obtained was flash chromatographed on silica gel eluding with mixtures of hexane and ethyl acetate to afford the title compound (1.265 g, 46percent). m.p. 43.5¡ã-44¡ã C. 1 H NMR (CDCl3, 300 MHz) delta 4.04 (s, 3H), 8.50 (bs, 1H), 8.60 (bs, 1H). MS (DCl/NH3) m/e 217/219 (M+H)+, 234/236 (M+H+NH3)+.

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 16298-03-6.

Reference:
Patent; Abbott Laboratories; US5250548; (1993); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 32974-92-8, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 32974-92-8, name is 1-(3-Ethylpyrazin-2-yl)ethanone belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

(1) 2-acetyl-3-ethylpyrazine (420 ul, 3 mmol) was dissolved in methanol (20 ml).After dissolution,4-Benzyl-3-thiosemicarbazide (501 mg 3 mmol) was added.well mixed,The mixed solution was refluxed at 65 C for 4 h.filter,The filtrate evaporates at room temperature.There are pale yellow crystals,Filter again,Wash 2-3 times with absolute ethanol,Obtaining a ligand L5;

The synthetic route of 1-(3-Ethylpyrazin-2-yl)ethanone has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Guangxi Normal University; Yang Feng; Sun Zewen; Zhao Lei; Liang Hong; (16 pag.)CN109796501; (2019); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 74290-67-8, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 74290-67-8, name is 2-Amino-5-bromo-3-methylpyrazine belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

To a solution of I-69 (300 mg, 0.6 mmol) in DMF (10 mL) are added I-87 (140 mg, 0.7 mmol), tetrakis(triphenylphosphine)palladium (0) (70 mg, 0.06 mmol) and 2M Na2CO3 (1.5 mL, 3.0 mmol). The mixture is heated to 100 C. for 1 hour in a microwave reactor. The mixture is cooled down and is extracted with H2O (20 mL) and EtOAc (30 mL). The combined organic layer is dried with MgSO4 and is filtered. The filtrate is concentrated and the residue is purified by silica gel flash column chromatography with 10% MeOH in CH2Cl2 as the eluent to afford the title compound (200 mg). Example 176-180, Table 1-the reaction is run at 120 C.Example 176-180, Table 1-the reaction is run at 120 C. [0509] Example 184-185, Table 1-the reaction is run at 120 C

The synthetic route of 2-Amino-5-bromo-3-methylpyrazine has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Boehringer Ingelheim International GmbH; BYLOCK, Lars Anders; US2013/195879; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem

Synthetic Route of 768-05-8, In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 768-05-8, name is Pyrazinoic acid hydrazide belongs to Pyrazines compound, it is a common compound, a new synthetic route is introduced below.

General procedure: 2.3. General procedure for the synthesis of N’-(2r,4c-diaryl-3-azabicyclo[3.3.1]nonan-9-ylidene)pyrazine-2-carbohydrazide(8-14)The quest for the synthesis of N’-(2r,4c-diaryl-3-azabicyclo[3.3.1]nonan-9-ylidene)pyrazine-2-carbohydrazide (8-14) wasaccomplished in two steps as outlined in Scheme 1. A mixture of2r,4c-diaryl-3-azabicyclo[3.3.1]nonan-9-one (1-7) (1 mmol),commercially available pyrazine-2-carbohydrazide (PZH)(1.5 mmol) in methanol and chloroform mixture (1:1 v/v), andcatalytic amount of acetic acid (0.1 mL) was added and refluxed for2-3 h. On the completion of reaction, a solid mass was formed.After cooling to room temperature, the precipitate was filtered offand washed with cold mixture of ethanol and water. The crude product was recrystallized from ethanol [16].

The synthetic route of Pyrazinoic acid hydrazide has been constantly updated, and we look forward to future research findings.

Reference:
Article; Mangalam; Sebastian Antony Selvan; Sankar; Journal of Molecular Structure; vol. 1129; (2017); p. 305 – 312;,
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. 33332-25-1, name is Methyl 5-chloropyrazine-2-carboxylate, A new synthetic method of this compound is introduced below., Product Details of 33332-25-1

Sodium hydride (60% dispersion in mineral oil) (6.4 g, 0.16 mol) was added portionwise to a solution of 7-hydroxy-1, 2,4, 5-tetrahydro-benzo [DIAZEPINE-3-CARBOXYLIC acid TERT-BUTYL ester (PCT Int. APPL. (2002), WO 02/40471) (40 g, 0.15 mol) in dry dimethylformamide (200 ml) cooled to 5 C over 15 minutes. After 15 minutes, the mixture was allowed to warm to room temperature and stirred for 60 minutes. The mixture was cooled in an ice-water bath and methyl 5-chloro-2-pyrazinecarboxylate (31.2 g, 0.18 mol) was added portionwise. The mixture was allowed to warm to room temperature and stirred for 18 hours. The mixture was poured onto water (500 mi) and ice (500 ml) and stirred until the ice had melted. The resulting solid was collected by filtration, washed with water and dissolved in ethyl acetate (1500 ML). The ethyl acetate layer was washed with brine (200 ML), dried under sodium sulfate and evaporated in vacuo. The crude product was purified by column chromatography eluting with a mixture of ethyl acetate: hexane (1: 2) to afford the title compound (35.07 g).

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; GLAXO GROUP LIMITED; WO2004/56369; (2004); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem