Tag: M.W:100-200

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 2075-46-9 as follows. name: 4-Nitro-1H-pyrazole

Dissolving 5.0 g of 4-nitropyrazole in 160 mL of ethanol, and then adding 0.8 g of 10 wt% Pd/C to the above solution; Hydrogen was introduced into the reaction solution and allowed to react overnight at room temperature; after the TLC detection reaction was completed, the insoluble matter was filtered off with diatomaceous earth; Evaporation of the ethanol solvent gave pure intermediate 2 as a red solid 3.6 g.

According to the analysis of related databases, 2075-46-9, the application of this compound in the production field has become more and more popular.

Electric Literature of 1260243-04-6,Some common heterocyclic compound, 1260243-04-6, name is Ethyl 5-amino-1H-pyrazole-4-carboxylate, molecular formula is C6H9N3O2, 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.

3.1) Ethyl 5-amino-1H-pyrazole-4-carboxylate (15.5 g, 0.1 mol) obtained in step 1)And p-fluorophenyl-4,4,4-trifluorobutanedione (23.4 g, 0.1 mol) obtained in step 2) were placed in a vessel;3.2) After dissolving the mixture in the vessel with 50 mL of glacial acetic acid,To obtain a mixture E,The container was placed under an electric heating condition,Heating up to 115°C ;3.3) The mixture E was heated to reflux,After 7 hours,Cooling, standing, precipitation of yellow – green needle – like solid;The solid was filtered, washed, dried,To give ethyl 5- (4-fluorophenyl) -7-trifluoromethylpyrazolo [1,5-a] pyrimidine-3-carboxylate;The article used for the washing process is cold glacial acetic acid.The mass of the obtained product 5- (4-fluorophenyl) -7-trifluoromethylpyrazolo [1,5-a] pyrimidine-3-carboxylate was 27.05 g.Yield: 76.63percent.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 5-amino-1H-pyrazole-4-carboxylate, its application will become more common.

Synthetic Route of 37622-90-5,Some common heterocyclic compound, 37622-90-5, name is Ethyl 4-pyrazolecarboxylate, molecular formula is C6H8N2O2, 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 suspension of LAH (45.2 mL, 45.2 mmol, 1M in THF) in a flame-dried flask was added a solution of ethyl 1H-pyrazole-4-carboxylate (3.17 g, 22.6 mmol) in THF (20 mL) dropwise at 0 C. The reaction mixture was gradually warmed to rt and stirred overnight. The reaction mixture was cooled in an ice bath, and carefully quenched by sequential dropwise addition of 1.36 mL H2O, and 10 mL of 1M NaOH, followed by 20 min of stirring. Solid MgSO4 was added, the ice bath was removed, and stirring was continued for 30 min at rt. Solids were removed by filtration through Celite® and washed with THF, then MeOH. The combined filtrate was evaporated to give (1H- pyrazol-4-yl)methanol (1.75 g, 78.9percent), as a white solid.1H NMR (500MHz, DMSO-d6) delta 12.58 (br. s., 1H), 7.58 (s, 1H), 7.40 (s, 1H), 4.74 (t, J=5.5 Hz, 1H), 4.37 (d, J=5.2 Hz, 2H).

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 4-pyrazolecarboxylate, its application will become more common.

Electric Literature of 1621-91-6, These common heterocyclic compound, 1621-91-6, name is 1H-Pyrazole-3-carboxylic acid, 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.

Scheme 33–Route to Preferred Groups 49 [4,3-d] ring fusion Nitration of pyrazole-3-carboxylic acid followed by reduction gives 4-aminopyrazole-3-carboxylic acid.

The synthetic route of 1621-91-6 has been constantly updated, and we look forward to future research findings.

Synthetic Route of 31037-02-2,Some common heterocyclic compound, 31037-02-2, name is Ethyl 5-amino-1-methyl-1H-pyrazole-4-carboxylate, molecular formula is C7H11N3O2, 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.

Step 3.1 : 5-Amino-1 -methyl- 1 H-pyrazole-4-carboxylic acid5-Amino-1-methyl-1 H-pyrazole-4-carboxylic acid ethyl ester (16.4 g, 97 mmol) is heated to reflux in 97 ml of 2 M sodium hydroxide solution and 100 ml of ethanol. After complete saponification, the mixture is acidified to pH 5 with 6 M HCI solution, and the formed precipitate is isolated by filtration. The product is dried at the high vacuum pump and the title compound is isolated as a white solid. HPLC: tR = 4.65 min; MS-ES+: (M+H)+ = 142 ; TLC*: Rf = 0.24.

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Ethyl 5-amino-1-methyl-1H-pyrazole-4-carboxylate, its application will become more common.

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 17635-45-9 as follows. Safety of 4-Pyrazol-1-yl-phenylamine

General procedure: A mixture of aniline derivative 1a?1e (1 mmol) and 1 cm3concentrated hydrochloric acid was thoroughly stirred atroom temperature for 15 min and then cooled to 0 C. Asolution containing 0.069 g sodium nitrite (1 mmol) in 10 cm3 water was added dropwise to the initial mixtureduring 40 min. An aqueous solution of aromatic nucleophile(1 mmol) in NaOH 10percent (5 cm3) was then addedand the resulted mixture was stirred for 1 h at 0 C. Theprecipitated solid was filtered, washed with water and dried in air. The products 2a?2c, 2e, 2f, 2m, and 2o were purifiedby recrystallization in ethanol, but preparative TLC (nhexane?EtOAc, 4:1) was applied for purification of products2d, 2g?2l, 2n, and 2p.

According to the analysis of related databases, 17635-45-9, the application of this compound in the production field has become more and more popular.

Application of 10010-93-2, 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. 10010-93-2, name is 3-Methyl-5-(trifluoromethyl)-1H-pyrazole belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.

General procedure: A mixture of compound 26 (200 mg, 0.342 mmol), 4-(trifluoromethyl)-1H-pyrazole (93 mg, 0.68 mmol), copper(I) iodide (13 mg, 0.068 mmol), 8-hydroxyquinoline (20 mg, 0.14 mmol), and potassium carbonate (95 mg, 0.68 mmol) in DMSO (2 mL) was stirred at 130 C under N2 atmosphere overnight. The mixture was quenched with saturated aqueous NH4Cl solution and the insoluble materials were removed by filtration. The filtrate was extracted with AcOEt. The organic layer was successively washed with water and brine, dried over MgSO4, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/AcOEt = 70:30 to 30:70) and crystallized from AcOEt-iPr2O to give the title compound as a pale yellow solid (80 mg, 0.13 mmol, 37%).

The synthetic route of 3-Methyl-5-(trifluoromethyl)-1H-pyrazole has been constantly updated, and we look forward to future research findings.

Synthetic Route of 26308-42-9, 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. 26308-42-9 name is 3-Ethyl-1-methyl-1H-pyrazole-5-carboxylic acid, 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.

General procedure: Pyrazole acid 9a-k (3 mmol) and thionyl chloride (7.5 mmol)were successively added to 20 mL 1,2-dichloroethane, the mixturewere stirred under reflux for 3 h and then concentrated underreduced pressure, the crude products were added in drops into asolution of 5?a-f (5a-h) (3 mmol) and trimethylamine (6 mmol) inTHF (15 mL).The reaction mixturewas stirred under the 0 C for thenight. After reaction the mixture was poured in Na2CO3 solutionand aqueous phase was extracted with ethyl acetate (2 20 mL).The combined organic phase was washed with saturated salt water(2 20 mL), dried over anhydrous Na2SO4, and concentrated underreduced pressure and the residue was purified by silica gel columnchromatography.

At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3-Ethyl-1-methyl-1H-pyrazole-5-carboxylic acid, and friends who are interested can also refer to it.

Electric Literature of 37622-90-5, These common heterocyclic compound, 37622-90-5, name is Ethyl 4-pyrazolecarboxylate, 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) 1-(4-Hydroxymethyl-benzyl)-1H-pyrazole-4-carboxylic acid ethyl ester A mixture of (4-Chloromethyl-phenyl)-methanol (600 mg, 3.8 mmol), ethyl 1H-pyrazole-4-carboxylate (537 mg, 3.8 mmol) and potassium carbonate (2.6 g, 19 mmol) in 30 mL acetone was stirred at 50 C. for 3 h. The mixture was filtrated and concentrated in vacuo. The crude was purified by preparative HPLC (Waters Sunfire Prep C18 PBD 5 um, 30*100 mm, 5 to 100% ACN and 0.1% TFA, flow 40 ml/min) to yield the title compound. LCMS (method A) RtA=1.403 min; [M+H]+=261.0.

The synthetic route of 37622-90-5 has been constantly updated, and we look forward to future research findings.

3469-69-0, name is 4-Iodopyrazole, 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. Application In Synthesis of 4-Iodopyrazole

1-Methyl-4-iodopyrazole (18) 4-Iodopyrazole (1) (5.0 g 25.7 mmole) was dissolved in DMF (50 mL), potassium carbonate (4.26 g 30.9 mmole) was added and stirred (2 mins) before iodomethane (1.76 mL, 4.01 g 28.3 mmole) was added. The reaction was stirred rapidly at r.t. for 17 hrs. It was filtered through a Celite pad. The filtrate was evaporated to a small volume, about 10 mL, using a rotary evaporator with a high vac. pump and the water bath at 60 C. Water (120 mL) was added to the residue. The filtered solids on the Celite pad were washed with ethyl acetate (50 ml) and these washings were used to extract the product from the aqueous. The aqueous was extracted with more ethyl acetate (2*50 mL). The combined organics were washed with water (3*30 mL) and with brine; dried and evaporated to give the title compound as a solid 4.56 g, 85%. 1H-NMR (CDCl3, 500 MHz): delta 3.93 (s, 3H) 7.42 (s, 1H), 7.50 (s, 1H).

The synthetic route of 3469-69-0 has been constantly updated, and we look forward to future research findings.