Day: June 10, 2021

Electric Literature of 5334-40-7, 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. 5334-40-7, name is 4-Nitro-1H-pyrazole-3-carboxylic acid, This compound has unique chemical properties. The synthetic route is as follows.

Step 1: Into a 100 mL round bottom flask containing a solution of methyl 4-nitro-1H-pyrazole- 3-carboxylate (5.0 g, 29 mmol) in dimethylformamide (50 mL) were added anhydrous potassium carbonate (8.0 g, 58 mmol) and 2-iodopropane (5.8 mL, 58 mmol) at 0 oC and the mixture was stirred at room temperature for 16 h. The reaction mixture was filtered through celite and washed with ethyl acetate. The filtrate was washed with water and brine, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure. The residue was purified flash chromatography eluting with ethyl acetate in petroleum ether (10-20percent) to afford a mixture of regioisomers, methyl 1-isopropyl-4-nitro-1H-pyrazole-5-carboxylate (2.2 g, 35percent yield) as a colorless oil and methyl 1-isopropyl-4-nitro-1H-pyrazole-3-carboxylate as an oil. For methyl 1- isopropyl-4-nitro-1H-pyrazole-5-carboxylate; 1H NMR (CD3OD, 400 MHz): delta 8.16 (s, 1H), 4.75-4.71 (m, 1H), 4.04 (s, 3H), 1.52 (d, J = 6.6 Hz, 6H). For methyl 1-isopropyl-4-nitro-1H- pyrazole-3-carboxylate; 1H NMR (CD3OD, 400 MHz): delta 8.68 (s, 1H), 4.66-4.59 (m, 1H), 3.95 (s, 3H), 1.55 (d, J = 6.7 Hz, 6H).

The chemical industry reduces the impact on the environment during synthesis 4-Nitro-1H-pyrazole-3-carboxylic acid. I believe this compound will play a more active role in future production and life.

Reference:
Patent; MERCK SHARP & DOHME CORP.; LIM, Jongwon; ALTMAN, Michael, D.; BRUBAKER, Jason, D.; GIBEAU, Craig, R.; (94 pag.)WO2016/144847; (2016); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

These common heterocyclic compound, 15754-60-6, name is 1-(tert-Butyl)-1H-pyrazole, 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. HPLC of Formula: C7H12N2

Flash vacuum pyrolysis reactions were carried out by distillation of the substrate in vacuo through an electrically heated silica furnace tube (35 × 2.5 cm). Products were trapped in a U-tube situated at the exit point of the furnace and cooled with liquid N2. Conditions were first established on a small scale (20 mg) where the product(s) were dissolved in a deuterated solvent and analyzed directly by 1H NMR spectroscopy. Larger-scale pyrolyses, involving 0.1 g or more of substrate, were usually removed from the trap by solution in CH2Cl2 (30mL). The precursors and pyrolysis conditions [quantity of precursor, inlet temperature (Ti), furnace temperature (Tf), pressure range (P), and pyrolysis time (t)] and yields are stated. This compound was too volatile for normal inlet conditions. It was therefore cooled in an acetone-dry ice bath, which was slowly removed to allow sublimation (20 mg, Ti acetone/dry ice bath, Tf 600-850 C, P 0.03 Torr, t 15 min).

The synthetic route of 1-(tert-Butyl)-1H-pyrazole has been constantly updated, and we look forward to future research findings.

Reference:
Article; Mackay, Martha; Nortcliffe, Andrew; McNab, Hamish; Hulme, Alison N.; Synthesis; vol. 47; 2; (2015); p. 242 – 248;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Adding a certain compound to certain chemical reactions, such as: 17635-44-8, name is 3,4,5-Tribromopyrazole, belongs to pyrazoles-derivatives 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 17635-44-8, Safety of 3,4,5-Tribromopyrazole

EXAMPLE 40 Preparation of 3,4,5-Tribromopyrazole-1-ethanol acetate (ester) A quantity (3.04 g., 0.01 mole) of 3,4,5-tribromopyrazole was dissolved in 70 ml. acetone and 2.76 g. (0.02 mole) solid anhydrous potassium carbonate was added. The mixture was heated at the reflux temperature with stirring for 10 minutes and after cooling, 1.85 g. (0.011 mole) of 2-bromoethyl acetate was added. This reaction mixture was heated at the reflux temperature for 12 hrs. cooled, filtered, and the acetone removed under reduced pressure. The resultant oil consisted of a mixture of the desired acetate and the corresponding alcohol. The mixture was dissolved in pyridine (15 ml.) and treated with acetic anhydride (3.06 g., 0.03 mole) at 0 C. This reaction mixture was kept at about 25 C. overnight, and then poured into 200 ml. of ice water. The precipitate that formed was collected on a filter, and washed with water. After drying and recrystallizing from hexane there was obtained 3,4,5-tribromopyrazole-1-ethanol acetate (ester) having a melting point at 64 to 67 C. Analysis: Calc’d. for C7 H7 Br3 N2 O2: C, 21.51; H, 1.81; N, 7.17; Br, 61.33. Found: C, 21.88; H, 1.95; N, 7.14; Br, 61.42.

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.

Reference:
Patent; The Upjohn Company; US4084955; (1978); A;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Some common heterocyclic compound, 35691-93-1, name is Ethyl 3,5-dimethyl-1H-pyrazole-4-carboxylate, molecular formula is C8H12N2O2, 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. Safety of Ethyl 3,5-dimethyl-1H-pyrazole-4-carboxylate

A microwave vial was charged with ethyl 3,5-dimethyl-1 H-pyrazole-4-carboxylate (1.00 g, 5.95 mmol), methyl vinyl sulfone (0.521 ml, 5.95 mmol), K2CO3 (2.465 g, 17.84 mmol) and DMF (15 ml), and the mixture was irradiated for 30 minutes at 135 C in a personal microwave reactor. The reaction mixture was diluted with EtOAc, washed with brine and dried over magnesium sulfate. The solvent was removed to give ethyl 3,5-dimethyl-1-[2-(methylsulfonyl)ethyl]-1 H-pyrazole-4-carboxylate (1.61 g, 99 % yield). 1 H NMR (400 MHz, CHLOROFORM-d) delta ppm 4.47 (t, J=6.2 Hz, 2 H), 4.30 (q, J=IA Hz, 2 H), 3.65 (t, J=6.2 Hz, 2 H), 2.61 (s, 3 H), 2.60 (s, 3 H), 2.42 (s, 3 H), 1.37 (t, J=IA Hz, 3 H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 35691-93-1, its application will become more common.

Reference:
Patent; SMITHKLINE BEECHAM CORPORATION; WO2008/157273; (2008); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

82560-12-1, name is 3-Amino-5-tert-butylpyrazole, belongs to pyrazoles-derivatives compound, is considered to be a conventional heterocyclic compound, which is widely used in drug synthesis. The chemical synthesis route is as follows. Quality Control of 3-Amino-5-tert-butylpyrazole

To a solution of 5-amino-3-tert-butylpyrazole (3.93 g, 28.2 mmol) in CH2Cl2 (140 mL) was added di-tert-butyl dicarbonate (6.22 g, 28.5 mmol) in one portion. The resulting solution was stirred at room temp. for 13 h, then diluted with EtOAc (500 mL). The organic layer was washed with water (2 x 300 mL), dried (MgSO4) and concentrated under reduced pressure. The solid residue was triturated (100 mL hexane) to give the desired carbamate (6.26 g, 92%): mp 63-64 C; TLC Rf (5% acetone/95% CH2Cl2); 1H-NMR (DMSO-d6) delta 1.15 (s, 9H), 1.54 (s, 9H), 5.22 (s, 1H), 6.11 (s, 2H); FAB-MS m/z ((M+H)+).

The synthetic route of 82560-12-1 has been constantly updated, and we look forward to future research findings.

Reference:
Patent; Bayer Pharmaceuticals Corp.; EP1047418; (2005); B1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Adding a certain compound to certain chemical reactions, such as: 89717-64-6, name is 4-Bromo-3-nitro-1H-pyrazole, belongs to pyrazoles-derivatives 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 89717-64-6, Formula: C3H2BrN3O2

To a solution of 4-bromo-3- nitro-lH-pyrazole (1.3 g, 6.8 mmol) in DMF (15 mL) was added benzyl bromide (1.72 g, 10.1 mmol) and K2CO3 (1.86 g, 13.5 mmol) at room temperature. The reaction mixture was stirred at 80 C for 12 h. After cooling down to room temperature, the mixture was diluted with water (40 mL) and extracted with EtOAc (40 mL x 2). The combined organic layers were washed with water (30 mL) and brine (30 mL), dried over Na2S04, filtered and concentrated. The residue was purified by silica gel chromatography (eluted with petroleum ether/EtOAc from 0% to 20%) to give the l-benzyl-4-bromo-3-nitro-lH-pyrazole (1.5 g, Yield: 78%) as a yellow solid. ESI-LCMS (m/z): 282.0 [M+1]; 1HNMR (400 MHz, CD3OD): delta 8.05 (s, 1H), 7.43-7.32 (m, 5H), 5.41 (s, 2H) ppm

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 4-Bromo-3-nitro-1H-pyrazole, and friends who are interested can also refer to it.

Reference:
Patent; EPIZYME, INC.; CAMPBELL, John Emmerson; (178 pag.)WO2016/44666; (2016); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Application of 132712-71-1, A common heterocyclic compound, 132712-71-1, name is 3-Methyl-1H-pyrazol-5-ol, molecular formula is C4H6N2O, 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 well-stirred solution of isatin and malononitrile(1 mmol each) in ethanol (95%, 4 mL) was added dimedone,4-hydroxycoumarin, 4-hydroxy-N-methylquinolin-2-one,or 2-methyl-pyrazol-2-one [generated in situ from ethylacetoacetate and hydrazine hydrate, 1 mmol each]. To thissolution was added THAM (30 mol %) and stirring wascontinued at ambient temperature. Upon completion of thereaction (TLC), water (5 mL) was added and stirring wascontinued for 10 min more. Resultant solid product wasfiltered, washed repeatedly with water, and dried. The dried solid was washed thrice with hexaneechloroformmixture (1:1, v/v) and dried again. Resultant product didnot require any further purification.

The synthetic route of 132712-71-1 has been constantly updated, and we look forward to future research findings.

Reference:
Article; Khot, Supriya S.; Anbhule, Prashant V.; Desai, Uday V.; Wadgaonkar, Prakash P.; Comptes Rendus Chimie; vol. 21; 9; (2018); p. 814 – 821;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Adding a certain compound to certain chemical reactions, such as: 72760-85-1, name is 3-Amino-5-(methylthio)-1H-pyrazole-4-carbonitrile, belongs to pyrazoles-derivatives 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 72760-85-1, name: 3-Amino-5-(methylthio)-1H-pyrazole-4-carbonitrile

General procedure: An equimolar mixture of Int-I (chalcones) and Int-II (5-amino-3-(methylthio)-1H-pyrazole-4-carbonitrile) was refluxed in n-butanol for 4-5 h. The completion of reaction was confirmed by Thin Layer Chromatography using (6:4- hexane: ethyl acetate) as a mobile phase. The reaction mixture was then allowed to cool and the resulting solid was filtered and washed with diethyl ether to remove impurities. The procedure was repeated 3-4 times to free the product from impurities.

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.

Reference:
Article; Baluja, Shipra; Nandha, Kajal; Journal of Molecular Liquids; vol. 201; (2015); p. 90 – 95;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Adding a certain compound to certain chemical reactions, such as: 17635-45-9, name is 4-Pyrazol-1-yl-phenylamine, belongs to pyrazoles-derivatives 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 17635-45-9, Recommanded Product: 4-Pyrazol-1-yl-phenylamine

General procedure: A dry 50 mL capacity carousel reaction tube was charged with the relevant substituted indole (1.5 mmol), and this starting material dissolved in dry THF (12 mL). Oxalyl chloride (144 muL, 209 mg, 1.65 mmol) was added and the mixture stirred at room temp. After 24 h, either N,N-diisopropylethylamine (590 muL, 438 mg, 3.4 mmol) or 2,6-lutidine(396 muL, 364 mg, 3.4 mmol) was introduced to the reaction, followed by the relevant amine (1.8 mmol). The temperature was raised to 45 °C, and heating continued for 18 h. The solvent was evaporated, then the residue resuspended in a mixture of ethyl acetate (20 mL) and brine (10 mL) and stirred vigorously for 30 min. After passing through a liquid-liquid extraction column, ensuring washing through of the column with additional ethyl acetate, a second extraction was carried out with sat. NH4Cl (10 mL) in the same manner. Product solutions were then evaporated to dryness giving the crude indole-3-glyoxylamide derivatives, which were purified as necessary (see Supplementary Information for individual compound details). Typically, two sequential recrystallizations, from ethyl acetate-hexane followed by 2-propanol-water, afforded final products of good purity. For products derived from poorly nucleophilic anilines (p-1H-pyrazol-1-ylaniline,p-pyrrol-1-ylaniline and p-morpholinoaniline), a further modification was used. Immediately following introduction of the arylamine to the reaction mixture, DMAP (18 mg, 0.15 mmol, 10 molpercent) was added to assist the final step, as its use was found to enhance the extent of conversion in the final step in such cases.

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, 4-Pyrazol-1-yl-phenylamine, other downstream synthetic routes, hurry up and to see.

Reference:
Article; Thompson, Mark J.; Louth, Jennifer C.; Ferrara, Steven; Jackson, Matthew P.; Sorrell, Fiona J.; Cochrane, Edward J.; Gever, Joel; Baxendale, Sarah; Silber, B. Michael; Roehl, Henry H.; Chen, Beining; European Journal of Medicinal Chemistry; vol. 46; 9; (2011); p. 4125 – 4132;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

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. 948570-75-0, name is 1-(2-Methoxyethyl)-4-nitro-1H-pyrazole, A new synthetic method of this compound is introduced below., HPLC of Formula: C6H9N3O3

1-(2-methoxyethyl)-4-nitro-1H-pyrazole (84 mg, 0.49 mmol) and -chloro-6-(2,6-dichloro-3,5-dimethoxy phenyl)pyrido[3,4-d]pyrimidine (200 mg, 0.54 mmol) were dissolved into DMA (15 mL), then CuI (112 mg, 0.59 mmol), PivOH (15 mg, 0.15 mmol), K2CO3 (88 mg, 0.64 mmol) and Pd(PPh3)2Cl2 (34 mg, 0.05 mmol) were added, the mixture was heated to 140 C. under N2 and stirred for 1 h. The reaction was completed, and the mixture was concentrated to remove the sol vent by reduced pressure and separated by fast silica gel column (PE/EA 2:1) to obtain compound 6-(2,6-dichloro-3,5-dimethoxyphenyl)-2-(1-(2-methoxyethyl)-4-nitro-1H-pyrazol-5-yl)pyrido[3,4-d]pyrimidine (103 mg, yield 42%). MS m/z (ESI): 505 [M+1]+.

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; Abbisko Therapeutics Co., Ltd.; YANG, Fei; DENG, Haibing; YING, Haiyan; YU, Hongping; CHEN, Zhui; XU, Yaochang; (604 pag.)US2019/270742; (2019); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics