Day: October 27, 2020

504-29-0 , The common heterocyclic compound, 504-29-0, name is Pyridin-2-amine, 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.

75.2 g (0.80 mol) Of 2-aminopyridine was dissolved in 88.0 g (0.88 mol) of ethyl acrylate and 20 mL of acetic acid. The mixture was heated to 80C and stirred for 24 hours at the same temperature. -Solvent was removed under vacuum, and the title compound was isolated by vacuum distillation to obtain 77.0 g of ethyl 3-(2- pyridylamino)propionate as a white solid.Yield: 77.Og (49.67%); Purity by HPLC: 98.5%.

According to the analysis of related databases, 504-29-0, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MEGAFINE PHARMA (P) LTD.; MATHAD, Vijayavitthal Thippannachar; SOLANKI, Pavankumar Vrajlal; UPPELLI, Sekhar Babu; SARODE, Ganesh Gitaram; WO2015/128875; (2015); A2;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

With the rapid development and complex challenges of chemical substances, the synthesis of new drugs is usually one of the most effective ways to increase yield.13534-99-1, name is 2-Amino-3-bromopyridine, molecular formula is C5H5BrN2, molecular weight is 173.01, as common compound, the synthetic route is as follows.13534-99-1

equipped with a mechanical stirring three 500mL flask, 30g2- amino-3-bromo-pyridine, 52.8 g as an associated boronic acid pinacol ester, 300mL1,4- dioxane, 4.2gPd (dppf)2Cl2, 59.3g of anhydrous potassium acetate, purged with nitrogen three times, heated to about 80 open overnight.TLC the reaction was complete, cooling, filtration, the filter cake washed twice with 30mL dichloromethane and the filtrate was concentrated to dryness, 200mL of methanol and 20g active carbon was stirred at room temperature overnight, filtration.Concentrated to dryness to give an oil, and petroleum ether was added 15mL 200mL MTBE heating overnight, filtered to give 28g2-amino-4-boronic acid pinacol ester in a yield of 72.8%.

Statistics shows that 13534-99-1 is playing an increasingly important role. we look forward to future research findings about 2-Amino-3-bromopyridine.

Reference:
Patent; Shanghai Rainbow Chemistry Co.,Ltd; Wu, Gang; Yan, taotao; Wei, xianli; (13 pag.)CN102786543; (2016); B;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

626-64-2, The major producers of chemicals have been the Europe, Japan and China. Due to the growing call for a cleaner, greener environment, people will have to find innovative ways to maintain their relevance. Here is a compound 626-64-2, name is Pyridin-4-ol. This compound has unique chemical properties. The synthetic route is as follows.

9.5 g (0.10 mol) of 4-hydroxypyridine,, 21.5 g (0.11 mol) of 4-bromobutyric acid ethyl ester,0.5 g of 5% Pd / C catalyst,80 ml of ethanol was placed in a 300 ml autoclave, and the interior of the container was replaced with hydrogen.While introducing hydrogen gas into the vessel, the reactor was heated to 100 C. while stirring, and the reaction was carried out at a hydrogen pressure of 4.9 ¡Á 10 5 Pa for 9 hours.After allowing the reactor to cool down, disappearance of 4-hydroxypyridine was confirmed by TLC. The catalyst was removed by filtration, and the obtained reaction solution was concentrated.To the residue was added 100 ml of water and extracted with 60 ml of ethyl acetate, and the organic layer was dried and concentrated. After drying the obtained solid under reduced pressure, 18.3 g (85 mmol, yield 85%) of (4-hydroxy) -4-piperidinobutanoic acid ethyl ester was obtained.

While traditionally a conservative industry, chemical producers will need to modernize their PR strategies to stay relevant.we look forward to future research findings about 626-64-2, Pyridin-4-ol.

Reference:
Patent; TOKUYAMA CORPORATION; SEKI, MASAHIKO; YAMAMOTO, HIROMASA; (13 pag.)JP2018/24593; (2018); A;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Adding a certain compound to certain chemical reactions, such as: 18368-63-3, 2-Chloro-6-methylpyridine, 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, 18368-63-3, blongs to pyridine-derivatives compound. 18368-63-3

1, 1-dimethylethyl (6-methyl-2-Dyridinyl)acetateTo a stirred solution of tert-butyl acetate (1.013 mL, 7.50 mmol), 2-chloro-6-methylpyridine (638 mg, 5 mmol), chloro(2-di-t-butylphosphino-2′,4′,6′-tri-/’-propyl-1 , 1 ‘-biphenyl)[2-(2- aminoethyl)phenyl]palladium(ll) (34.3 mg, 0.050 mmol) in Toluene (10 mL) at 0 C in a 100-mL round bottom flask under N2 was added a solution of LHMDS (1 M in toluene) (15.00 mL, 15.00 mmol) pre-cooled to 0 C. The reaction was stirred for 30 minutes. LCMS indicated the reaction was complete, so it was poured into ammonium chloride (aqueous, saturated) and water (1 :1 , 40 mL), and extracted with ethyl acetate (3 x 100 mL). The combined organics were dried over sodium sulfate, filtered and concentrated. The residue was purified by flash chromatography (0-25% EtOAc in hexanes) to afford 1 , 1 -dimethylethyl (6-methyl-2-pyridinyl)acetate (918 mg, 4.43 mmol, 89 % yield) as a yellow oil. LC-MS(ES) m/z = 208 [M+H]+. 1 H NMR (400 MHz, DMSO-d6) delta ppm 1.41 (s, 9 H), 2.44 (s, 3 H), 3.68 (s, 1 H), 7.12 (t, J=7.33 Hz, 2 H), 7.64 (t, J=7.71 Hz, 1 H).

With the rapid development of chemical substances, we look forward to future research findings about 18368-63-3.

Reference:
Patent; GLAXOSMITHKLINE LLC; AXTEN, Jeffrey, Michael; GRANT, Seth, Wilson; HEERDING, Dirk, A.; MEDINA, Jesus, Raul; ROMERIL, Stuart, Paul; TANG, Jun; WO2011/119663; (2011); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Some common heterocyclic compound, 626-55-1, molecular formula is C5H4BrN, 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.626-55-1

Stage 1Methylpyridin-3-ylamine An amount of 100.1 g (633 mmol) of 3-bromopyridine was stirred with 160 ml (1280 mmol) of 8M methylamine in ethanol, 4 g (27.5 mmol) of 8-hydroxyquinoline and 2.2 g (11.5 mmol) of copper(I) iodide in an autoclave at 120 for 16 hours. The mixture was filtered with suction over sand/silica gel and concentrated, aqueous citric acid and cyclohexane were added to the residue, the aqueous phase was saturated with sodium chloride, admixed with dilute aqueous sodium hydroxide solution to a pH of 10 and extracted 6 times with ethyl acetate, and the combined organic phases were dried over MgSO4 and evaporated. The residue was distilled in a bulb tube under a membrane pump vacuum.Yield: 46.8 g (63% of theory), 1H-NMR (CD3CN) 2.75 (s, 3H), 4.3 (br, 1H), 6.85 (m, 1H), 7.05 (m, 1H), 7.8 (m, 1H), 7.95 (m, 1H)

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 626-55-1.

Reference:
Patent; BAYER CROPSCIENCE AG; US2010/305124; (2010); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The common heterocyclic compound, 151213-42-2, name is (4aR,7aR)-Octahydro-1H-pyrrolo[3,4-b]pyridine, molecular formula is C7H14N2, 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. 151213-42-2

General procedure: A mixture of 6-chloro-4-cyclopropyl-7-fluoro-1-oxo-1,4-dihydronaphthalene-2-carboxylic acid 1a (1 g, 3.5 mmol) with N-ethylpiperazine 2c (0.6 g, 5.25mmol) was loaded in a small flask fitted with a micro condenser, placed in the microwave reactor and irradiated for 25 min at 150C under solvent free conditions. The reaction progress was monitored by TLC. Upon completion of the process, addition of hot absolute ethanol (10 mL) to the reaction mixture was followed by filtration. The filtrate was concentrated and stored at room temperature for precipitation. The solid was filtered off and recrystallized from absolute ethanol to give compound 3c.

The synthetic route of 151213-42-2 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Mirzaie; Lari; Vahedi; Hakimi; Russian Journal of General Chemistry; vol. 86; 12; (2016); p. 2865 – 2869; Zh. Obshch. Khim.; vol. 86; 12; (2016); p. 2865 – 2869,5;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

5470-18-8 , The common heterocyclic compound, 5470-18-8, name is 2-Chloro-3-nitropyridine, molecular formula is C5H3ClN2O2, 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 3-nitro-2-chloropyridine (4.0 g, 25.2 mmol) in 15 mL 2-methoxyethanol was added methylamine (2.0 M in THF, 32 mL). The reactionwas stirred for 8 hr at 80 C in a sealed tube. After cooling to rt, the reaction mixture was evaporated to afford 15 quantitatively (3.6 g, 23.2 mmol). 1H NMR (500 MHz, CDCl3) delta 8.47 – 8.37 (m, 2H), 8.20 (s, 1H), 6.64 (dd, J = 8.3, 4.4 Hz, 1H), 3.17 (d, J = 4.8 Hz, 3H). 13C NMR (126 MHz, CDCl3) delta 156.0, 153.5, 135.4, 111.7, 28.4. HRMS (ESI+) m/z calcd for C6H8N3O2+ 154.0617, found 154.0610.

According to the analysis of related databases, 5470-18-8, the application of this compound in the production field has become more and more popular.

Reference:
Article; Pollock, Julie A.; Kim, Sung Hoon; Katzenellenbogen, John A.; Tetrahedron Letters; vol. 56; 44; (2015); p. 6097 – 6099;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

69045-84-7, 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. 69045-84-7, name is 2,3-Dichloro-5-(trifluoromethyl)pyridine. A new synthetic method of this compound is introduced below.

(R) -2- (4-hydroxyphenoxy) propionic acid (3 g),DMF (35 ml), slowly adding K2CO3 (4.55 g),Heating up to 70 ~ 80 ,Stir for 1h,Was added dropwise 2,3-dichloro-5-trifluoromethylpyridine (3.56 g)Keep at 70 ~ 80 for 8h,Stop the reaction,Naturally cooled to room temperature,The mixture was poured into ice water (200 mL)The pH was adjusted to 4 to 5 using dilute hydrochloric acid, extracted with ethyl acetate,Organic phase washed,dry,(R) -2- [4- (5-trifluoromethyl-3-chloropyridin-2-yloxy) phenoxy]Propionic acid brown liquid 5.03 g,Yield 84.4%.

At the same time, in my other blogs, there are other synthetic methods of this type of compound,69045-84-7, 2,3-Dichloro-5-(trifluoromethyl)pyridine, and friends who are interested can also refer to it.

Reference:
Patent; China Three Gorges University; Liu Qixing; Zhou Haifeng; Lu Guoren; Peng Yuqi; (9 pag.)CN106632293; (2017); A;,
Pyridine – Wikipedia,
Pyridine | C5H5N – 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. 5446-92-4, name is 2-Methoxy-5-nitropyridine. A new synthetic method of this compound is introduced below., 5446-92-4

General procedure: A stirred mixture of nitroarene 1 (1 mmol), allyl sulfone 2 (1.1 mmol), MgCl2 (60 mg, 0.62 mmol), and bis-trimethylsilylacetamide (BSA, 0.51 g, 0.64 mL, 2.5 mmol) in HMPA (2 mL) was treated with DBU (0.76 g, 0.75 mL 5.0 mmol). Stirring was continued for 2 days. After completion (disappearing of the nitroarene, TLC control), the reaction mixture was poured into saturated aqueous NH4Cl and extracted with ethyl acetate (3¡Á25 mL). After drying with MgSO4 and removal of the solvent the crude product was chromatographed Colorless crystals; mp 173-176 C (hexane/ethyl acetate); 1H NMR (400 MHz, CDCl3) delta 1.50 (s, 9H), 2.40 (s, 3H), 3.96 (s, 3H), 7.06 (d, J=8.5 Hz, 1H), 7.26-7.29 (m, 2H), 7.98 (d, J=7.5 Hz, 2H), 8.16 (d, J=9.0 Hz, 1H), 8.51 (s, 1H); 13C NMR (100 MHz, CDCl3) delta 21.62, 30.13, 38.45, 54.69, 117.13, 120.36, 128.50, 129.18, 135.14, 138.14, 140.20, 142.27, 142.91, 144.23, 162.13, 167.12; numax (film from CH2Cl2) 2886, 1679, 1460, 1296, 1201, 1150, 1067, 984, 746 cm-1; EIMS (70 eV) m/z (% relative intensity): 355 (29), 307 (16), 306 (54), 305 (100), 292 (15), 291 (44), 275 (17), 264 (19), 249 (37), 138 (15), 91 (16); HRMS (EI) for C20H22N2O3S calcd 370.1351; found 370.1347.

At the same time, in my other blogs, there are other synthetic methods of this type of compound,5446-92-4, 2-Methoxy-5-nitropyridine, and friends who are interested can also refer to it.

Reference:
Article; Anczkiewicz, Karolina; Krolikiewicz, Magdalena; Wrobel, Zbigniew; Wojciechowski, Krzysztof; Tetrahedron; vol. 71; 23; (2015); p. 3924 – 3931;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

6419-36-9, 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. 6419-36-9, name is 2-(Pyridin-3-yl)acetic acid hydrochloride, molecular formula is C7H8ClNO2, The 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 1-Preparation of risedronic acid A mixture of (3-pyridyl) acetic acid hydrochloride (10 g 0.06 moles) and phosphorous acid (47 g, 0.58 moles) is slowly added with phosphorus oxychloride (28.8 g 0.19 moles). The fluid mixture is warmed up to 60-70C for 24 hours, then added with 60 ml water at the same temperature. The mixture is refluxed for 6 hours, added with 0.3 g charcoal and hot-filtered through celite. The clarified solution is added with 160 ml acetone. The resulting precipitate is filtered, suspended in 50 ml water, dissolved at pH 7.5 (+/-0.2) with 30% sodium hydroxide. The resulting solution is acidified to pH 0.8 (+/-0. 2) and the precipitate is filtered and dried under vacuum at 40-50C to constant weight. 9. 8 g pure risedronic acid is obtained (yield: 60%).

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. 6419-36-9, 2-(Pyridin-3-yl)acetic acid hydrochloride, other downstream synthetic routes, hurry up and to see.

Reference:
Patent; LYOGEN LIMITED; WO2005/63779; (2005); A2;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem