Category: 1621-91-6

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. 1621-91-6, name is 1H-Pyrazole-3-carboxylic acid, A new synthetic method of this compound is introduced below., name: 1H-Pyrazole-3-carboxylic acid

Ethyl 1H-pyrazole-3-carboxylate (6) A 100 mL Schlenk tube was dried under vacuum, filled with nitrogen and charged with 0.5 g (4.461 mmol, 1.0 eq) 1H-pyrazol-3-carboxylic acid which was dissolved in 20 mL EtOH. After adding 1.31 g (0.72 mL, 13.382 mmol, 3.0 eq) conc. H2SO4 the colorless reaction mixture was heated to reflux (100° C.) and stirred at this temperature for 4 h. TLC analysis (DCM/MeOH 95:5) indicated full conversion of the starting material. After cooling to rt the mixture was transferred to a flask to remove the solvent at a rotary evaporator. The colorless residue was diluted in 20 mL water and neutralized with 17 mL saturated aqueous NaHCO3 solution. Thereby a white solid precipitated. The aqueous layer was extracted with EtOAc (4*50 mL), dried over MgSO4 and the solvent was evaporated under reduced pressure to yield the pure title compound. yield: 582.5 mg (93percent); colorless solid; M.p.: 158-161° C.; Rf (DCM/MeOH 95:5): 0.42; 1H-NMR (300 MHz, CDCl3): delta (ppm)=10.69 (bs, 1H, NH), 7.84 (d, 4J=2.1 Hz, 1H, Ar-H), 6.86 (d, 4J=2.1 Hz, 1H, Ar-H), 4.43 (q, 3J=7.2 Hz, 2H, CH2), 1.41 (t, 3J=7.2 Hz, 3H, CH3); 13C-NMR (75.5 MHz, CDCl3): delta (ppm)=161.8 (C=O), 141.6 (Cq), 132.3 (CHAr), 107.8 (CHAr), 61.1 (CH2), 14.3 (CH3); GC-MS (NM-50_S2): tR=4.655 min (m/z=140.1, 98.0percent M+, BP: 95.0).

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

Reference:
Patent; Technische Universitaet Graz; Karl-Franzens-Universitaet Graz; Schweiger, Martina; Romauch, Matthias; Zimmermann, Robert; Mayer, Nicole; Breinbauer, Rolf; US9206115; (2015); B2;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

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. Recommanded Product: 1621-91-6

Dimethyl sulfate (236 g, 177 mL, 1.87 mol) was added dropwise over 45 min to a stirred solution of pyrazole-3-carboxylic acid (200 g, 1.78 mol) in 20% aqueous sodium hydroxide (850 mL) at 40 C. The reaction mixture was heated at 80 C for 2 h, cooled to room temperature, filtered, the filtrate acidified to pH 1 with concentrated HCI, the precipitate filtered, washed with water, and dried under vacuum to yield 1-methylpyrazole-5-carboxylic acid (85 g, 38%). The filtrate was concentrated in vacuo to 800 ML, extracted with chloroform (15X400 mL), the organic phase dried over anhydrous magnesium sulfate, concentrated in vacuo, and the residue recrystallized from isopropanol to yield 1-METHYLPYRAZOLE-3-CARBOXYLIC acid (74 g) as a white crystalline solid.

The synthetic route of 1H-Pyrazole-3-carboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK & CO., INC.; WO2004/58702; (2004); A2;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Related Products of 1621-91-6,Some common heterocyclic compound, 1621-91-6, name is 1H-Pyrazole-3-carboxylic acid, molecular formula is C4H4N2O2, 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.

Ste 1: (0582) Preparation of 4-bromo-1H-pyrazole-3-carboxylic acid: (0583) [00241] To a stirred solution of 1H-pyrazole-3-carboxylic acid (2.0 g, 17.85 mmol) in acetic acid (50 mL), bromine (1.2 mL, 23.21 mmol) was added at 0 C and the reaction mixture was stirred at room temperature for 16 h. The reaction mixture was diluted with water (150 mL) and extracted with ethyl acetate (3 x 100 mL). The combined organic layer was washed with brine solution, dried over anhydrous sodium sulfate, filtered and concentrated to afford the title compound 4-bromo-1H-pyrazole-3-carboxylic acid (3.4 g, crude) as off-white solid. (0584) Calculated (M+H): 190.94; Found (M+H): 191.0

These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 1H-Pyrazole-3-carboxylic acid, its application will become more common.

Reference:
Patent; LUC THERAPEUTICS; ANDERSON, David, R.; VOLKMANN, Robert, A.; MENNITE, Frank, S.; FANGER, Christopher; (390 pag.)WO2017/100591; (2017); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

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 1621-91-6 as follows. Formula: C4H4N2O2

b) Methyl lH-pyrazole-3-carboxylate lH-Pyrazole-3-carboxylic acid (15 g, 133.8 mmol) was dissolved in MeOH (250 ml). Concentrated H2S04 (30 ml) was added to the solution. The resulting mixture was refluxed for 12 h and concentrated. The residue obtained was quenched by saturated aqueous solution of NaHC03 and extracted with EtOAc. The organic layer was concentrated. Yield 12.05 g. 1H-NMR (400 MHz; CDC13): delta 3.98 (s, 3H), 6.86 (d, 1H), 7.85 (d, 1H), 1 1.9 (bs, 1H).

According to the analysis of related databases, 1621-91-6, the application of this compound in the production field has become more and more popular.

Reference:
Patent; ORION CORPORATION; TOeRMAeKANGAS, Olli; WOHLFAHRT, Gerd; SALO, Harri; RAMASUBRAMANIAN, Rathna, Durga; PATRA, Pranab, Kumar; MARTIN, Arputharaj, Ebenezer; HEIKKINEN, Terhi; VESALAINEN, Anniina; MOILANEN, Anu; KARJALAINEN, Arja; WO2012/143599; (2012); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Reference of 1621-91-6,Some common heterocyclic compound, 1621-91-6, name is 1H-Pyrazole-3-carboxylic acid, molecular formula is C4H4N2O2, 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 1 : To a mixture of 1 H-pyrazole-3-carboxylic acid (15.0 g, 134 mmol) and Cs2C03 (109 g, 335 mmol) in CH3CN (250 mL) was added CH3I (29.2 ml, 469 mmol) and the RM was stirred at rt for 14 h. The RM was filtered and filtrate was concentrated under reduced pressure, diluted with EtOAc and washed with water and brine before being dried. The solvent was evaporated under reduced pressure to give the crude product which was purified by CC (Si02; EtOAc/Hex) to yield the desired product (10.0 g, 53%). LC-MS (Method 3): m/z [M+H]+ = 141.3 (MW calc. 140.14); R, = 1.55 min.

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

Reference:
Patent; GRUeNENTHAL GMBH; VOSS, Felix; RITTER, Stefanie; NORDHOFF, Sonja; WACHTEN, Sebastian; OBERBOeRSCH, Stefan; KLESS, Achim; WO2015/22073; (2015); A1;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

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. Formula: C4H4N2O2

Dimethyl sulfate (236 g, 177 mL, 1.87 mol) was added dropwise over 45 min to a stirred solution of pyrazole-3-carboxylic acid (200 g, 1.78 mol) in 20% aqueous sodium hydroxide (850 mL) at 40 C. The reaction mixture was heated at 80 C for 2 h, cooled to room temperature, filtered, the filtrate acidified to pH 1 with concentrated HCI, the precipitate filtered, washed with water, and dried under vacuum to yield 1-methylpyrazole-5-carboxylic acid (85 g, 38%). The filtrate was concentrated in vacuo to 800 ML, extracted with chloroform (15X400 mL), the organic phase dried over anhydrous magnesium sulfate, concentrated in vacuo, and the residue recrystallized from isopropanol to yield 1-METHYLPYRAZOLE-3-CARBOXYLIC acid (74 g) as a white crystalline solid.

The synthetic route of 1H-Pyrazole-3-carboxylic acid has been constantly updated, and we look forward to future research findings.

Reference:
Patent; MERCK & CO., INC.; WO2004/58702; (2004); A2;,
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

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.

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. 1621-91-6, name is 1H-Pyrazole-3-carboxylic acid, A new synthetic method of this compound is introduced below., SDS of cas: 1621-91-6

Ethyl 1H-pyrazole-3-carboxylate (6) A 100 mL Schlenk tube was dried under vacuum, filled with nitrogen and charged with 0.5 g (4.461 mmol, 1.0 eq) 1H-pyrazol-3-carboxylic acid which was dissolved in 20 mL EtOH. After adding 1.31 g (0.72 mL, 13.382 mmol, 3.0 eq) conc. H2SO4 the colorless reaction mixture was heated to reflux (100° C.) and stirred at this temperature for 4 h. TLC analysis (DCM/MeOH 95:5) indicated full conversion of the starting material. After cooling to rt the mixture was transferred to a flask to remove the solvent at a rotary evaporator. The colorless residue was diluted in 20 mL water and neutralized with 17 mL saturated aqueous NaHCO3 solution. Thereby a white solid precipitated. The aqueous layer was extracted with EtOAc (4*50 mL), dried over MgSO4 and the solvent was evaporated under reduced pressure to yield the pure title compound. yield: 582.5 mg (93percent); colorless solid; M.p.: 158-161° C.; Rf (DCM/MeOH 95:5): 0.42; 1H-NMR (300 MHz, CDCl3): delta (ppm)=10.69 (bs, 1H, NH), 7.84 (d, 4J=2.1 Hz, 1H, Ar-H), 6.86 (d, 4J=2.1 Hz, 1H, Ar-H), 4.43 (q, 3J=7.2 Hz, 2H, CH2), 1.41 (t, 3J=7.2 Hz, 3H, CH3); 13C-NMR (75.5 MHz, CDCl3): delta (ppm)=161.8 (C=O), 141.6 (Cq), 132.3 (CHAr), 107.8 (CHAr), 61.1 (CH2), 14.3 (CH3); GC-MS (NM-50_S2): tR=4.655 min (m/z=140.1, 98.0percent M+, BP: 95.0).

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

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. Safety of 1H-Pyrazole-3-carboxylic acid

Example 10; Synthesis of (lR)-l-(l-naphthyI)-7V-({l-[4-(trifluoromethyl)phenyl]-lH-pyrazol-3- yl}methyl)ethanamineStep 1. A 500 mL round-bottomed flask was charged with l//-pyrazole-3-carboxylic acid 59 (5.0 g, 45 mmol), 100 mL of MeOH, and 10 drops of concentrated sulfuric acid. This mixture was heated to reflux and heating was continued for 12 h. After cooling to room temperature, the solvent was removed and the residue was dissolved in EtOAc and saturated aqueous NaHCO3. The layers were separated and the organic layer was dried and concentrated to give methyl lH-pyrazole-3-carboxylate 60.

The synthetic route of 1H-Pyrazole-3-carboxylic acid has been constantly updated, and we look forward to future research findings.

Synthetic Route of 1621-91-6, 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. 1621-91-6, name is 1H-Pyrazole-3-carboxylic acid belongs to pyrazoles-derivatives compound, it is a common compound, a new synthetic route is introduced below.

b) Methyl 1H-pyrazole-3-carboxylate 1H-Pyrazole-3-carboxylic acid (15 g, 133.8 mmol) was dissolved in MeOH (250 ml). Concentrated H2SO4 (30 ml) was added to the solution. The resulting mixture was refluxed for 12 h and concentrated. The residue obtained was quenched by saturated aqueous solution of NaHCO3 and extracted with EtOAc. The organic layer was concentrated. Yield 12.05 g. 1H-NMR (400 MHz; CDCl3): delta 3.98 (s, 3H), 6.86 (d, 1H), 7.85 (d, 1H), 11.9 (bs, 1H).

The synthetic route of 1H-Pyrazole-3-carboxylic acid has been constantly updated, and we look forward to future research findings.