Day: October 23, 2020

16063-70-0, 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 16063-70-0, name is 2,3,5-Trichloropyridine. This compound has unique chemical properties. The synthetic route is as follows.

General procedure: To a stirred solution of 4a (74.5 g, 410 mmol) in DMF (450 mL) was added NaH (60% dispersion in oil, 19.7 g, 491 mmol) at 0 C and the mixture was stirred at the temperature for 30 min. Then 2,3-dichloro-5-(trifluoromethyl)pyridine (60.0 mL, 433 mmol) was added to the mixture, which was allowed to warm to room temperature, and stirred at room temperature for 1 h and at 50 C for 1 h. The reaction was quenched with sat. NH4Cl on ice-bath and extracted with EtOAc and the combined organic layer was washed with water and brine, dried over MgSO4, filtered and concentrated under reduced pressure. The residual solid was purified by silica gel chromatography (hexane-EtOAc, 9:1 to 2:1) to give a pale-yellow solid, which was recrystallized from EtOAc/hexane to give 5a (79.0 g, 53%) as white crystals.

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 16063-70-0, 2,3,5-Trichloropyridine.

Reference:
Article; Rikimaru, Kentaro; Wakabayashi, Takeshi; Abe, Hidenori; Tawaraishi, Taisuke; Imoto, Hiroshi; Yonemori, Jinichi; Hirose, Hideki; Murase, Katsuhito; Matsuo, Takanori; Matsumoto, Mitsuharu; Nomura, Chisako; Tsuge, Hiroko; Arimura, Naoto; Kawakami, Kazutoshi; Sakamoto, Junichi; Funami, Miyuki; Mol, Clifford D.; Snell, Gyorgy P.; Bragstad, Kenneth A.; Sang, Bi-Ching; Dougan, Douglas R.; Tanaka, Toshimasa; Katayama, Nozomi; Horiguchi, Yoshiaki; Momose, Yu; Bioorganic and Medicinal Chemistry; vol. 20; 10; (2012); p. 3332 – 3358;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

145100-50-1 ,Some common heterocyclic compound, 145100-50-1, molecular formula is C7H4F6N2O4S2, 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.

2-[iV,lambdar-Bis(trifluoromethansulfonyl)amino]pyridine (13.2 g, 37.0 mmol) was added to a stirred solution ofi-3d-OH (15.6 g, 37.9 mmol), triethylamine (6.50 rnL546.6 mmol) and DMAP (256 mg, 2.10 mmol) in DCM (270 mL) at 0 “C. After approximately 2 h, the reaction mixture was poured into saturated aqueous sodium bicarbonate and extracted three times with EtOAc. The combined organic extracts were washed with saturated aqueous sodium bicarbonate and brine, dried (sodium sulfate) and concentrated in vacuo. The crude residue was purified by flash chromatography on silica gel (gradient elution; 30%-80% EtOAc/hexanes as eluent) to afford i-3d. m/z (ES) 545 (MH)+. 1HNMR (500 MHz, CDCl3): delta 8.97 (s, 2H)5 8.61 (d, IH, J= 3.0 Hz), 7.57 (d, 2H, J= 8.4 Hz), 7.53 (m, IH), 7.53 (d, 2H3 J- 8.0 Hz), 7.37 (d, IH, J= 8.7 Hz)5 5.95 (s, 2H), 3.15 (m, IH), 2.41 (s, 6H)5 1.78 (s, 3H), 0.89 (d, 3H, J= 6.7 Hz), 0.86 (d5 3H, J= 6.9 Hz).

According to the analysis of related databases, 145100-50-1, the application of this compound in the production field has become more and more popular.

Reference:
Patent; MERCK & CO., INC.; WO2008/30369; (2008); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

5446-92-4 , The common heterocyclic compound, 5446-92-4, name is 2-Methoxy-5-nitropyridine, molecular formula is C6H6N2O3, 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.

Preparation of 5-Methoxy-1H-pyrrolo[3,2-b]pyridine-3-carbaldehyde (Formula 10); 2-Methoxy-5-nitro-pyridine (Formula 6, 4 g, 25.6 mmole) and 4-chlorophenoxyacetonitrile (Formula 7, 4.8 g, 28.5 mmole) were dissolved in THF (58 mL). The resulting solution was slowly added to a solution of t-BuOK (6.3 g, 56.3 mmole) in THF dry (60 mL) at -10 C. The reaction mixture was stirred for 3 h at -10 C., and then water was added. The aqueous layer was extracted with EtOAc. The combined organic layers were dried on Na2SO4 and evaporated to give a crude that was purified by silica gel column chromatography (eluent: petroleum ether/EtOAc 8:2) to give (6-methoxy-3-nitro-pyridin-2-yl)-acetonitrile (Formula 8, Yield: 50%. MS (m/z): 194.1 (MH+)).To a solution of (6-methoxy-3-nitro-pyridin-2-yl)-acetonitrile (Formula 8, 1 g, 5.18 mmole) in EtOH (30 mL), 10% Pd/C was added. The mixture was hydrogenated at 45 psi at room temperature overnight. The catalyst was filtered off and the solvent was evaporated. The crude product was purified by silica gel column chromatography (eluent: petroleum ether/EtOAc 8:2) to give 5-methoxy-1H-pyrrolo[3,2-b]pyridine (Formula 9, Yield: 64%. MS (m/z): 149 (MH+).To a solution of 5-methoxy-1H-pyrrolo[3,2-b]pyridine (Formula 9, 498 mg, 3.36 mmole) in 33% acetic acid (5.2 mL), hexamethylenetetramine (714 mg, 5.05 mmole) was added. The reaction mixture was refluxed for 4 hours. After cooling, the reaction was extracted with EtOAc. The combined organic layers were dried on Na2SO4 and evaporated to give a crude that was purified twice by silica gel column chromatography (eluent: methylene chloride/MeOH 95:5) to give 5-methoxy-1H-pyrrolo[3,2-b]pyridine-3-carbaldehyde (Formula 10, Yield: 27%. MS (m/z): 177.17 (MH+)).

According to the analysis of related databases, 5446-92-4, the application of this compound in the production field has become more and more popular.

Reference:
Patent; Wyeth; US2009/298820; (2009); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

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. 766-11-0, name is 5-Bromo-2-fluoropyridine, molecular formula is C5H3BrFN, 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. 766-11-0

Step 1: Synthesis of 5-bromo-2-fluoro-pyridine-3-carbaldehyde.[0217] A solution of lithium di-zso-propylamine (5 mL, 35 mmol) in anhydrous THF (40mL) was cooled to -78 C under nitrogen and n-butyl lithium (2.5 M in hexanes, 12 mL, 30mmol) was added. The mixture was then stirred at -78 C for 15 min before 5-bromo-2-fluoro-pyridine (5 g, 28 mmol) was added. The resulting mixture was then stirred at -78 Cfor 90 min. 7V-formylpiperidine (4 mL, 36 mmol) was added very rapidly to the suspensionat -78 C and the mixture stirred vigorously for 60 sec. The reaction was immediately quenched by the addition of a 10 % (w/v) aqueous solution of citric acid. The mixture waswarmed to room temperature and distributed between water and dichloromethane. Theaqueous phase was extracted three times with dichloromethane and the organic phases werecombined, dried over sodium sulfate, filtered and concentrated. Crystallization of the crudeproduct from cyclohexane afforded 5-bromo-2-fluoro-pyridine-3-carbaldehyde (2.993 g,52% yield) as pale beige flaky crystals.

The chemical industry reduces the impact on the environment during synthesis 766-11-0, I believe this compound will play a more active role in future production and life.

Reference:
Patent; SGX PHARMACEUTICALS, INC.; WO2006/15124; (2006); A2;,
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. 53939-30-3, name is 5-Bromo-2-chloropyridine. A new synthetic method of this compound is introduced below., 53939-30-3

9.3 ml (9.5 g, 190.2 mmol) hydrazine hydrate are added to a solution of 1.8 g (9.5 mmol) 5-bromo-2-chloropyridine in 25 ml ethanol at RT, while stirring, and the mixture is then stirred at 90 C. for 46 h. After concentration of the reaction mixture in vacuo, the residue is stirred in water and the solid is filtered off, washed with water and diethyl ether and dried in vacuo.Yield: 0.8 g (44% of th.)LC-MS (Method 8): Rt=0.50 min; MS (ESIpos): m/z=188 [M+H]+;1H-NMR (400 MHz, DMSO-d6): delta=8.02 (d, 1H), 7.66 (s, 1H), 7.58 (dd, 1H), 6.69 (d, 1H), 4.16 (s, 2H).

At the same time, in my other blogs, there are other synthetic methods of this type of compound,53939-30-3, 5-Bromo-2-chloropyridine, and friends who are interested can also refer to it.

Reference:
Patent; BAYER SCHERING PHARMA AKTIENGESELLSCHAFT; US2010/305085; (2010); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

452-58-4, 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 452-58-4, name is 2,3-Diaminopyridine. This compound has unique chemical properties. The synthetic route is as follows.

A solution of pyridinediamine (IX), (X), (45.8 mmoles), acetic acid (458.0 mmoles) in PPA (50 ml) was heated to 135-14O0C for 2-4 h under nitrogen atmosphere. After completion of reaction, cooled, transferred the reaction to 250 ml of cold water, charcoal was added and the mixture filtered over a celite bed. The filtrate was basified with aq. ammonia solution till the pH~10-12. Extracted the basified reaction with ethyl acetate (250 ml X3), dried the ethyl acetate layer with sodium sulfate and distilled off the solvent completely to residue. To the residue hexane (50 ml) was added and filtered to get the desired compound (XI and XII). Table 6 : Imdiazopyridines (XI), (XII):

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 452-58-4, 2,3-Diaminopyridine.

Reference:
Patent; MASSACHUSETTS INSTITUTE OF TECHNOLOGY; PRESIDENT AND FELLOWS OF HARVARD COLLEGE; GENZYME CORPORATION; WO2009/137081; (2009); A2;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

19524-06-2, 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. 19524-06-2, name is 4-Bromopyridine hydrochloride. This compound has unique chemical properties. The synthetic route is as follows.

4-Bromopyridine hydrochloride (20.0 g, 102.9 mmol) was partitioned between EtOAc and 5% NaHCO3. The layers were separated, and the aqueous phase extracted with EtOAc. The combined organic extracts were washed with water and brine, dried over Na2SO4, and evaporated under reduced pressure in a 40 C. bath to provide 13.7 g (84%) of a volatile oil which was used immediately in the next step

If you are interested in these compounds, you can also browse my other articles.Thank you for taking the time to read this article. I hope you enjoyed it, 19524-06-2, 4-Bromopyridine hydrochloride.

Reference:
Patent; Pfizer Inc.; US2008/90861; (2008); A1;,
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.52334-81-3, name is 2-Chloro-5-trifluoromethylpyridine, molecular formula is C6H3ClF3N, molecular weight is 181.54, as common compound, the synthetic route is as follows.52334-81-3

2-chloro-5-trifluoromethylpyridine (13.7 g) was dissolved in ethanol (96 ml), thiourea (5.7 g) was added to the mixture, and the mixture was heated to reflux for 3 hours. After allowing the mixture to be cooled to room temperature, an aqueous solution (19.2 ml) of potassium hydroxide (6.4 g) was added to the mixture, and the mixture was heated to reflux for 1 hour. After allowing the mixture to be cooled to room temperature, diluted aqueous solution of potassium hydroxide (20 ml) was added to the mixture, and the mixture was washed with methylene chloride. With acetic acid, pH of the mixture was adjusted to about 6, and the mixture was extracted with methylene chloride. The mixture was washed with water, and dried over magnesium sulfate. The solvent was removed under reduced pressure and the obtained residue was washed with hexane/ethyl acetate, to give 2-mercapto-5-trifluoromethylpyridine (5.1 g). 1H-NMR (200 MHz, CDCl3) delta 4.55 (2H, s), 7.25 to 7.50 (1H, s), 7.59 (2H, d, J = 8.8 Hz), 7.69 (1H, dd, J = 8.4, 2.2 Hz), 8.16 (2H, d, J = 8.8 Hz), 8.69 (1H, s)

Statistics shows that 52334-81-3 is playing an increasingly important role. we look forward to future research findings about 2-Chloro-5-trifluoromethylpyridine.

Reference:
Patent; Takeda Chemical Industries, Ltd.; EP1422228; (2004); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Adding some certain compound to certain chemical reactions, such as: 16013-85-7, name is 2,6-Dichloro-3-nitropyridine, 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 16013-85-7. 16013-85-7

Prior synthesis of pyrido[3,2-d]pyrimidines utilized ethoxyethanol and aniline for substitution on 3 (Scheme 1) whereas for substituted anilines, strong bases such as LDA were used to facilitate the reaction. Both methods suffer from long durations and stringent reaction conditions, respectively. A simpler and versatile synthetic route to obtain 4-18 from 3 was envisioned using appropriate anilines at reflux in isopropanol at 120 C, a highly versatile reaction process that provided good yields (75-83%). Reduction of the nitro group was performed using iron in cone. HCl (Bechamp reduction) or using H2/Pd to give quantitative yields. Cyclization of the resultant intermediate with chlorformamidine in dimethylsulfone at 140 C provided the desired target compounds.

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 16013-85-7.

Reference:
Patent; DUQUESNE UNIVERSITY OF THE HOLY SPIRIT; GANGJEE, Aleem; (140 pag.)WO2017/31176; (2017); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

115473-15-9, Adding a certain compound to certain chemical reactions, such as: 115473-15-9, 5,6,7,7a-Tetrahydrothieno[3,2-c]pyridin-2(4H)-one hydrochloride, 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, 115473-15-9, blongs to pyridine-derivatives compound.

To a reaction flask equipped with a stirrer, a condenser and a thermometer was added 19.2 g of 5,6,7,7a-tetrahydrothieno[3,2-c]pyridin-2(4H)-one, which was then dispersed in 80 mL dichloromethane and cooled to 0 C. under stirring. 30.4 g of triethylamine were added to the mixture. After addition of 15.2 g of 3-cyanobenzyl bromide to the reaction system in batches, the reaction mixture was heated to reflux and continued to react for 5 h (completion of the reaction was monitored by TLC). The reaction liquid was washed with water (3¡Á80 mL). Then the dichloromethane layer was separated, fully dried over anhydrous sodium sulfate, and filtered. The dichloromethane was evaporated off under reduced pressure to obtain 20.8 g light yellow solid product (HPLC: 96.4%). Rf=0.45 [single point, developing solvent: v (petroleum ether): v (ethyl acetate)=1:2]. MS, m/Z: 270.0 (M).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route,115473-15-9, its application will become more common.

Reference:
Patent; TIANJIN INSTITUTE OF PHARMACEUTICAL RESEARCH; LIU, Dengke; LIU, Ying; YUE, Nan; CHEN, Furong; TAN, Chubing; ZHOU, Yunsong; LIU, Peng; ZHAO, Yigui; ZHI, Deguang; LIU, Mo; LIU, Bingni; HUANG, Changjiang; TANG, Lida; US2013/72521; (2013); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem