Day: January 11, 2021

These common heterocyclic compound, 1904-31-0, name is 1-Methyl-1H-pyrazol-3-amine, 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. Safety of 1-Methyl-1H-pyrazol-3-amine

A solution of 1 -methyl-1 -/-pyrazol-3-amine (2 g, 20.6 mmol,) in AcOH (50 mL) was treated with 2,5-hexane dione (4.9 g, 43.29 mmol) at ambient temperature under nitrogen atmosphere. The resulting reaction mixture was heated to 100 ¡ãC for 1 h then stirred at ambient temperature for 5 h. The reaction mixture was concentrated under reduced pressure and azeotroped with toluene. The crude product was purified by column chromatography on silica gel using 10percent EtOAc- hexanes eluent to give 3-(2,5-dimethyl-1 H-pyrrol-1 -yl)-1 -methyl-1 H-pyrazole as a liquid (2.5 g, 69percent). 1 H NMR (300 MHz, CDCI3): delta = 7.39 (d, J = 2.1 Hz, 1 H), 6.15 (d, J = 2.4 Hz, 1 H), 5.84 (s, 2H), 3.92 (s, 3H), 2.10 (s, 6H).

The synthetic route of 1-Methyl-1H-pyrazol-3-amine has been constantly updated, and we look forward to future research findings.

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. 26621-44-3, name is 3-Nitro-1H-pyrazole, This compound has unique chemical properties. The synthetic route is as follows., Formula: C3H3N3O2

To a stirred solution of 3-nitro-lH-pyrazole 94 (5.0 g, 44.24 mmol) in acetonitrile (50 mL) was added K2CO3 (12 g, 88.49 mmol) followed by 2-bromoethan-l-ol (5.4 g, 44.24 mmol) and the reaction mixture was stirred at 90 C for 16 h. Progress of the reaction was monitored by LC-MS. Volatiles were removed under reduced pressure and the crude residue thus obtained was diluted with ethyl acetate (150 mL) and water (100 mL). Organic layer was separated off and aqueous layer was further extracted with ethyl acetate (100 mL x 2). (1695) Combined organic layer was dried over sodium sulphate and evaporated under reduced pressure to get the crude residue which was purified by silica gel column chromatography (100-200 mesh) using 30% EtOAc in hexanes to afford 95 (4 g, 58%) as a pale yellow viscous oil. 1H NMR (400 MHz, DMSO-d6) delta 3.78 (q, J=5.38 Hz, 2H), 4.27 (t, 5.14J H=z, 2H), 5.00 (t, J5=.38 Hz, 1H), 7.03 (d, 2J.4=5 Hz, 1H), 7.99 (d, 2.45J H=z, 1H).

According to the analysis of related databases, 26621-44-3, the application of this compound in the production field has become more and more popular.

Electric Literature of 51985-95-6, A common heterocyclic compound, 51985-95-6, name is Methyl 5-hydroxy-1-methyl-1H-pyrazole-3-carboxylate, molecular formula is C6H8N2O3, 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 methyl S-hydroxy-l-methyl-S-pyrazolecarboxylate (Sucrow, W.;Auffenberg-Weddige, K.; Grosz, K. P.; Bredthauer, G.; Pickardt, J. Chemische Berichte 1983, 116(4), 1525-30., 10 g, 64 mmol), in acetonitrile (200 ml) is added POBr3 (95g, 322 mmol) and the resulting mixture is heated in a sealed flask at 80 0C for 15 hours. After 15 hours the reaction mixture is cooled to room temperature and added to a cooled (0 0C) solution of saturated aqueous sodium bicarbonate. After the addition, the product is extracted into ethyl acetate 3x. The combined organic layers are decolorized with charcoal, dried (anhydrous Na2SO4), filtered and evaporated in vacuo to give the product as a brown oil, that solidified upon standing 11.5g, (72%), LC/MS ESI m/z (M+H)+ = 220.2.

The synthetic route of 51985-95-6 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. 5334-40-7, name is 4-Nitro-1H-pyrazole-3-carboxylic acid, A new synthetic method of this compound is introduced below., Product Details of 5334-40-7

20 g of 4-nitropyrazolo-l-carboxylic acid (1) (127.32 mM) as a starting material was drop wisely added to the reaction solution dissolving 11.10 ml of acetyl chloride (381.96 mM) in 350 ml of methanol to react together and finally 23.69 g of methyl- 4-nitro-lH-pyrazole-3-carboxylate hydrochloride was obtained (yield: 90percent).

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.

Some common heterocyclic compound, 141573-95-7, name is Ethyl 3-(difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylate, molecular formula is C8H10F2N2O2, 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. category: pyrazoles-derivatives

3 -Difluoromethyl-1-methyl-1H-pyrazole-4-carboxylic acid ethyl ester (53.3 mg) was dissolved in liquid ammonia (10 mL). A column (500mm x 4.6mm i.d.) packed with aluminium oxide (4.501 g) was placed in the oven and the temperature was raised to 100C before pure liquid ammonia was pumped through. Then pure liquid ammonia was pumped through the system at 0.3 mLmin”1 and the pressure adjusted to 100 bar using an adjustable back pressure regulator.The system was left pumping pure liquid ammonia for 10 minutes then switched to the reaction solution at 0.3mL min^forSO min. At this time, pure liquid ammonia was pumped through the system for another 1 hour at 0.3mL min”1. All the reaction solution was collected as it exited the reaction column, at the end of the reaction, the ammonia was allowed to evaporate, the residue was dissolved in methanol and analysed by HPLC (87-91% conversion, 98.4% selectivity).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 141573-95-7, its application will become more common.

Adding a certain compound to certain chemical reactions, such as: 155600-99-0, name is 3,5-Dibromo-1-methyl-4-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 155600-99-0, SDS of cas: 155600-99-0

Production example 8 3-bromo-5-tert-butylamino-1-methyl-4-nitropyrazole 1.5 g (5.26 mmoles) of 3,5-dibromo-1-methyl-4-nitropyrazole are heated in a solution of 20 ml tert-butylamine in 30 ml ethanol for 20 hours at boiling temperature. After cooling, the reaction mixture is poured on 150 ml water, the separated product is filtered and washed with 100 ml water. After vacuum drying, 1.14 g (78 percent of theory) of 3-bromo-5-tert-butylamino-1-methyl-4-nitropyrazole are obtained in the form of pale yellow flakes with a melting point of 75 to 77 C. 1 H-NMR (60 MHz, DMSO-d6):=5.35 (s; 1H; –NH; exchanges with D2 O), 3.75 (s; 3H; N–CH3) and 1.20 ppm (s; 9H; –C(CH3)3). MS (70 eV): m/e=277 (M+).

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, 3,5-Dibromo-1-methyl-4-nitro-1H-pyrazole, other downstream synthetic routes, hurry up and to see.

Application of 138786-86-4, 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. 138786-86-4 name is Methyl 4-nitro-1H-pyrazole-3-carboxylate, This 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.

(2); To dried methanol (830ml) was carefully added sodium metal (6.71g), and the mixture was ice-cooled after sodium pieces are completely dissolved. Thereto were added compound (1) (43.61g) and then methyl iodide (43.64ml), and the mixture was stirred at 60?70C for 4 hours. After concentrated in vacuo, to the residue was chloroform and the solution was washed with aqueous saturated sodium bicarbonate solution and saturated brine, and dried. After removal of the solvent, the residue was purified with silica gel column chromatography (hexane:ethyl acetate=4:1?1:1) to give compound (2) (17.0g) as a yellow oil, and compound (3) (26.8g) as a colorless powder. Compound (2): APCI-MS (m/e): 186 (M+H)+ 1HNMR(500MHz/DMSO-d6 (ppm):3.95(s,3H),4.00(s,3H),8.37(s,1H) Compound (3): APCI-MS (m/e): 186 (M+H)+ 1HNMR(500MHz/DMSO-d6)delta(ppm):3.94(s,3H),4.00(s,3H),8.95(s,1H)

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

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., COA of Formula: C4H3N3O4

In a 250 mL round bottom flask, 7.5 g (36.6 mmol) of crude I-b’ was added. 4-nitro-1H-pyrazole-3-carboxylic acid 6.3 g (40.1 mmol), EDC¡¤HCl 8.4 g (44.0 mmol), HOBt 6.0g (44.4mmol) and anhydrous DMF 100mL, Stir at room temperature for 24 h. The disappearance of the starting material by TLC (methanol: chloroform = 1:10). The reaction solution was poured into 200 mL of ice water. A large amount of pale yellow solid is precipitated, Rest, Thinking about a yellow solid, The obtained crude product was recrystallized from ethyl acetate and methanol to give (I-e) 11.1 g. The yield was 88.2%.

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 5334-40-7.

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. 37687-24-4, name is Diethyl 3,5-pyrazoledicarboxylate, A new synthetic method of this compound is introduced below., Recommanded Product: Diethyl 3,5-pyrazoledicarboxylate

NaOH (3.53 g, 88 mmol) was added to a solution of diethyl 1H-pyrazole-3,5- dicarboxylate (5.35 g, 25.2 mmol) in acetonitrile (40 mL). After 30 mi 2- chloroethanamine hydrochloride (3.22 g, 27.7 mmol) and tetrabutylammonium hydrogen sulfate (0.43 g, 1.26 mmol) were added. The mixture was refluxed for 20 h. Aftercooled, conc. HC1 (5 mL) was added. The mixture was extracted with CH2C12, washed with brine. The combined organic layers were dried over Na2SO4, filtered and concentrated. Normal phase chromatography afforded Intermediate 138 (2.72 g, 52%) as a white solid. ?H NMR (500MHz, DMSO-d6) oe 8.39 (br s, 1H), 7.07 (s, 1H), 4.40 (dd, J6.7, 5.5 Hz, 2H), 4.27 (q, J7.2 Hz, 2H), 3.68 – 3.61 (m, 2H), 1.28 (t, J=7.0 Hz, 3H).LC-MS(ESI) m/z: 210.1 [M+H].

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 of 3524-32-1, 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. 3524-32-1, name is 5-Amino-1,3-dimethylpyrazole, This compound has unique chemical properties. The synthetic route is as follows.

To a solution of 9-((4-chloro-l H-pyrazol- l-yl)methyl)-4-(2- (rnethylsulfonyl)pyrimidin-4-yl)-8,9-dihydro-7H-6-oxa-l,2,2al-triazabenzo[cd]azulene (15- 4b, 200 mg, 0.44 mmol), 2,5-dimethylpyrazol-3-amine (149.5 mg, 1.34 mmol) in DMSO (2 mL) was added NaH (35.80 mg, 28 mmol, 60% mineral oil dispersion). The reaction was stirred at RT for 45 min, quenched with water and extracted with EtOAc (3 x 20 mL). The combined extracts were washed with 5% citric acid, brine, dried (Na2S04), filtered and concentrated in vacuo. The crude product was purified by Si02 chromatography (ISCO 12 g column) eluting with a MeOH/DCM gradient (0 to 8% MeOH) to afford 95 mg (88.5%) of the title compound as yellow solid.

The chemical industry reduces the impact on the environment during synthesis 5-Amino-1,3-dimethylpyrazole. I believe this compound will play a more active role in future production and life.