Tag: M.W=100-150

Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Pyrazoles are a class of compounds that have the ring C3N2 with adjacent nitrogen atoms.Notable drugs containing a pyrazole ring are celecoxib (celebrex) and the anabolic steroid stanozolol. Computed Properties of 37622-90-5.

Kwak, Se Hun;Daugulis, Olafs research published 《 N-Aminopyridinium Ylide-Directed, Copper-Promoted Amination of sp² C-H Bonds》, the research content is summarized as follows. N-Aminopyridinium ylides were used as monodentate directing groups for copper-promoted C-H/N-H coupling of sp² C-H bonds with pyrazoles, imidazoles, and sulfonamides. Reactions proceed in fluorinated alc. solvents at elevated temperatures and require use of 1.3-3 equiv of copper(II) acetate. This appears to be the first method for copper-promoted C-H/N-H coupling directed by a removable monodentate auxiliary in absence of added ligands.

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, Computed Properties of 37622-90-5

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Pyrazoles are a class of compounds that have the ring C3N2 with adjacent nitrogen atoms.Notable drugs containing a pyrazole ring are celecoxib (celebrex) and the anabolic steroid stanozolol. SDS of cas: 37622-90-5.

Lavagnino, Marissa N.;Liang, Tao;MacMillan, David W. C. research published 《 HARC as an open-shell strategy to bypass oxidative addition in Ullmann-Goldberg couplings》, the research content is summarized as follows. Herein, an alternative aryl halide activation strategy, in which the critical oxidative addition (OA) mechanism was replaced by a halogen abstraction-radical capture (HARC) sequence that allowed the generation of the Cu(III)-aryl intermediate albeit via a photoredox pathway was presented. This alternative mechanistic paradigm decoupled the bond-breaking and bond-forming steps of the catalytic cycle to enable the use of many previously inert aryl bromides. Overall, this mechanism allowed access to both traditional C-N adducts at room temperature as well as a large range of previously inaccessible Ullmann-Goldberg coupling products including sterically demanding ortho-substituted heteroarenes, e.g., I.

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, SDS of cas: 37622-90-5

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles and pyrimidines have diverse biological and pharmacological activities. 2075-46-9, formula is C3H3N3O2, Name is 4-Nitro-1H-pyrazole. There are a number of antimicrobial compounds containing pyrazole moiety as the core unit. Reference of 2075-46-9.

Le, Tuan;Courant, Thibaut;Merad, Jeremy;Allain, Clemence;Audebert, Pierre;Masson, Geraldine research published 《 s-Tetrazine Dyes: A Facile Generation of Photoredox Organocatalysts for Routine Oxidations》, the research content is summarized as follows. A series of organic dyes derived from s-tetrazine have been synthesized, and their photophys. and electrochem. properties systematically investigated. Testing these compounds as photoredox catalysts in a model oxidative C-S bond cleavage of thioethers has led us to identify new classes of active s-tetrazines. Moreover, some of them can be formed in situ from com. available 3,6-dichlorotetrazine making this photocatalyzed C-S bond functionalization simple and highly practical.

2075-46-9, 4-Nitro-1H-pyrazole, also known as 4-Nitropyrazole, is a useful research compound. Its molecular formula is C3H3N3O2 and its molecular weight is 113.08 g/mol. The purity is usually 95%.

4-Nitropyrazole, is a building block for the synthesis of various pharmaceutical compounds, including inhibitors, and therapeutic agents. It can be used for the synthesis of highly selective, brain-penetrant aminopyrazole LRRK2 Inhibitor, as a potentially viable treatment for Parkinson’s disease., Reference of 2075-46-9

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. 2075-46-9, formula is C3H3N3O2, Name is 4-Nitro-1H-pyrazole. Pyrazole is a weak base, with pKb 11.5 (pKa of the conjugated acid 2.49 at 25 °C).Pyrazole used as a ligand to prepare organometallic compounds. Synthetic Route of 2075-46-9.

Lei, Zhi-Chao;Li, Na;Yu, Nai-Rong;Ju, Wei;Sun, Xiao-Na;Zhang, Xue-Ling;Dong, Hai-Juan;Sun, Jian-Bo;Chen, Li research published 《 Design and Synthesis of Novel Celastrol Derivatives as Potential Anticancer Agents against Gastric Cancer Cells》, the research content is summarized as follows. Gastric cancer (GC) is a common malignant disease worldwide, and finding novel agents and strategies for the treatment of GC are of urgent need. Celastrol (CEL) is a well-known natural product with antineoplastic activity. In this study, pyrazole analogs were introduced at the C-29 position of CEL. A total of 24 new derivatives were designed, synthesized, and evaluated for their mechanism and antitumor activity in vitro and in vivo. Among them, compound 21 exhibited the best activity against BGC-823 cells (IC₅₀ = 0.21 ± 0.01μM). Further biol. studies showed that 21 significantly raised the reactive oxygen species (ROS) levels to activate the apoptotic pathway, causing mitochondrial dysfunction in BGC-823 cells. In addition, 21 also arrested cells in the G2/M phase to induce tumor cell apoptosis. In a nude mouse tumor xenograft model, 21 exhibited a better tumor inhibition rate (89.85%) than CEL (inhibition rate 76.52%). Taken together, the present study has provided an anticancer lead compound candidate, 21, and has revealed that increased ROS generation may be an effective strategy in the treatment of GC.

Synthetic Route of 2075-46-9, 4-Nitro-1H-pyrazole, also known as 4-Nitropyrazole, is a useful research compound. Its molecular formula is C3H3N3O2 and its molecular weight is 113.08 g/mol. The purity is usually 95%.

4-Nitropyrazole, is a building block for the synthesis of various pharmaceutical compounds, including inhibitors, and therapeutic agents. It can be used for the synthesis of highly selective, brain-penetrant aminopyrazole LRRK2 Inhibitor, as a potentially viable treatment for Parkinson’s disease., 2075-46-9.

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles can be selectively lithiated at different carbons and subsequently react with electrophiles depending on the substitution patterns. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. 1-Methyl-5-(trifluoromethyl)pyrazole underwent deprotonation and subsequent carboxylation mainly or exclusively at either the 4-position of the heterocycle or at the nitrogen-attached methyl group. Application of C6H8N2O2.

Lei, Zhi-Chao;Li, Na;Yu, Nai-Rong;Ju, Wei;Sun, Xiao-Na;Zhang, Xue-Ling;Dong, Hai-Juan;Sun, Jian-Bo;Chen, Li research published 《 Design and Synthesis of Novel Celastrol Derivatives as Potential Anticancer Agents against Gastric Cancer Cells》, the research content is summarized as follows. Gastric cancer (GC) is a common malignant disease worldwide, and finding novel agents and strategies for the treatment of GC are of urgent need. Celastrol (CEL) is a well-known natural product with antineoplastic activity. In this study, pyrazole analogs were introduced at the C-29 position of CEL. A total of 24 new derivatives were designed, synthesized, and evaluated for their mechanism and antitumor activity in vitro and in vivo. Among them, compound 21 exhibited the best activity against BGC-823 cells (IC₅₀ = 0.21 ± 0.01μM). Further biol. studies showed that 21 significantly raised the reactive oxygen species (ROS) levels to activate the apoptotic pathway, causing mitochondrial dysfunction in BGC-823 cells. In addition, 21 also arrested cells in the G2/M phase to induce tumor cell apoptosis. In a nude mouse tumor xenograft model, 21 exhibited a better tumor inhibition rate (89.85%) than CEL (inhibition rate 76.52%). Taken together, the present study has provided an anticancer lead compound candidate, 21, and has revealed that increased ROS generation may be an effective strategy in the treatment of GC.

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, Application of C6H8N2O2

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles are synthesized by the reaction of α,β-unsaturated aldehydes with hydrazine and subsequent dehydrogenation. 2075-46-9, formula is C3H3N3O2, Name is 4-Nitro-1H-pyrazole. Substituted pyrazoles are prepared by condensation of 1,3-diketones with hydrazine (Knorr-type reactions). For example, acetylacetone and hydrazine gives 3,5-dimethylpyrazole. Computed Properties of 2075-46-9.

Li, Bu-Tong;Li, Lu-Lin;Liu, Lin-Li research published 《 Thermal stability and detonation characters of nitro-substituted derivatives of pyrazole》, the research content is summarized as follows. A review. High-energy-d. compounds are designed successively by substituting the hydrogen atoms of 1H-pyrazole by the nitro group. The thermal stabilities are explored by the calculations of the heat of formation, bond orders, and bond dissociation energy at the B3PW91/6-311 + G(d,p) level. To evaluate the potential application as high-energy-d. compounds, the mol. d. (ρ), explosive heat (Q), the detonation velocity and detonation pressure are evaluated by using the empirical Kamlet-Jacobs equation. Based on our calculations, five mols. (3,4,5-trinitro-1H-pyrazole, 1,4,5-trinitro-1H-pyrazole, 1,3,5-trinitro-1H-pyrazole, 1,3,4-trinitro-1H-pyrazole, 1,3,4,5-tetranitro-1H-pyrazole) reached the balance between the stability and detonation characters and can be regarded as the potential high-energy-d. compounds

Computed Properties of 2075-46-9, 4-Nitro-1H-pyrazole, also known as 4-Nitropyrazole, is a useful research compound. Its molecular formula is C3H3N3O2 and its molecular weight is 113.08 g/mol. The purity is usually 95%.

4-Nitropyrazole, is a building block for the synthesis of various pharmaceutical compounds, including inhibitors, and therapeutic agents. It can be used for the synthesis of highly selective, brain-penetrant aminopyrazole LRRK2 Inhibitor, as a potentially viable treatment for Parkinson’s disease., 2075-46-9.

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole and its derivatives are considered a pharmacologically important active scaffold that possesses almost all types of pharmacological activities. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Pyrazole is a weak base, with pKb 11.5 (pKa of the conjugated acid 2.49 at 25 °C).Pyrazole used as a ligand to prepare organometallic compounds. Recommanded Product: Ethyl 4-pyrazolecarboxylate.

Li, Jing;Wu, Fangping;Liu, Xingguo;Zou, Yake;Chen, Huixiong;Li, Zheng;Zhang, Lei research published 《 Synthesis and bioevaluation of 1-phenyl-pyrazole-4-carboxylic acid derivatives as potent xanthine oxidoreductase inhibitors》, the research content is summarized as follows. A diverse library of 1-phenyl-pyrazole-4-carboxylic acid derivatives I [R = OCH₂CH₃, OCH₂CH(CH₃)₂, N(CH₃)₂, pyrrolidin-1-yl, etc.; R¹ = H, CH₃, CF₃; R² = CN, NO₂] was synthesized and evaluated for their inhibitory potency against xanthine oxidoreductase (XOR) in vitro and vivo, and the structure-activity relationship (SAR) analyses were also presented. Approx. half of the target compounds exhibited the inhibitory potency for XOR at the nanomolar level. Compounds I [R = N(CH₃)CH₂CH(CH₃)₂, pyrrolidin-1-yl, piperidin-1-yl; R¹ = H; R² = CN] emerged as the most potent xanthine oxidoreductase inhibitors with IC₅₀ values of 5.7, 5.7 and 4.2 nM, resp., in comparison to febuxostat (IC₅₀ of 5.4 nM). Steady-state kinetics measurements indicated that I [R = N(CH₃)CH₂CH(CH₃)₂, R¹ = H, R² = CN] is a mixed-type inhibitor. A computer mol. docking study of I [R = N(CH₃)CH₂CH(CH₃)₂, R¹ = H, R² = CN] bound to XOR was performed to gain an insight into its bind mode and SAR for the series. A potassium oxonate-hypoxanthine-induced hyperuricemia model in mice was chosen to further confirm the hypouricemic effects of I [R = N(CH₃)CH₂CH(CH₃)₂, piperidin-1-yl; R¹ = H; R² = CN] and the results demonstrated that I [R = N(CH₃)CH₂CH(CH₃)₂, R¹ = H, R² = CN] exhibits similar hypouricemic potency to febuxostat.

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, Recommanded Product: Ethyl 4-pyrazolecarboxylate

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Pyrazoles are a class of compounds that have the ring C3N2 with adjacent nitrogen atoms.Notable drugs containing a pyrazole ring are celecoxib (celebrex) and the anabolic steroid stanozolol. Recommanded Product: Ethyl 4-pyrazolecarboxylate.

Li, Kangkang;Li, Jin-Feng;Yin, Bing;Zeng, Fanlong research published 《 Investigation of NNN Pincer Ruthenium(II) Complexes with a Pendant Hydroxyl Group for N-Monomethylation of amines and Nitroarenes by Methanol》, the research content is summarized as follows. A family of air- and moisture-stable NNN pincer ruthenium(II) complexes with a pendant OH were developed, which exhibit unprecedented high reactivity and selectivity in N-monomethylation of amines and nitroarenes using methanol. The study reveals adopting the combination of 1H-pyrazole-1-yl and 3,5-dimethyl-4-hydroxyethyl-1H-pyrazol-1-yl as the two assistant arms of the pyridyl-backbone is a suitable choice. The mechanism study discloses that, during the catalytic cycle, dehydrogenation of methanol to form formaldehyde is a fast and reversible step.

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, Recommanded Product: Ethyl 4-pyrazolecarboxylate

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazole is an organic compound with the formula C3H3N2H. It is a heterocycle characterized by a 5-membered ring of three carbon atoms and two adjacent nitrogen atoms, which are in ortho-substitution. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Pyrazoles are a class of compounds that have the ring C3N2 with adjacent nitrogen atoms.Notable drugs containing a pyrazole ring are celecoxib (celebrex) and the anabolic steroid stanozolol. Recommanded Product: Ethyl 4-pyrazolecarboxylate.

Li, Peijun;Zbieg, Jason R.;Terrett, Jack A. research published 《 The Direct Decarboxylative N-Alkylation of Azoles, Sulfonamides, Ureas, and Carbamates with Carboxylic Acids via Photoredox Catalysis》, the research content is summarized as follows. A method for direct decarboxylative C-N coupling of carboxylic acids RC(O)OH (R = naphthalen-1-yl, 2-phenylpropan-2-yl, 1,2,3,4-tetrahydronaphthalen-1-yl, etc.) with a range of nitrogen nucleophiles, e.g., 5-(4-bromophenyl)-2H-1,2,3,4-tetrazol-2-yl has been described. This platform employs visible-light-mediated photoredox catalysis and an iodine(III) reagent to generate carbocation intermediates directly from aliphatic carboxylic acids via a radical-polar crossover mechanism. A variety of C-N bond-containing products, e.g., I are constructed from a diverse array of nitrogen heterocycles, including pyrazoles, imidazoles, indazoles, and purine bases. Furthermore, sulfonamides, ureas, and carbamates can also be utilized as a nucleophile to generate a selection of N-alkylated products. Notably, a two-step approach to construct free amines directly from the carboxylic acids is accomplished using Cbz-protected amine as a nucleophile.

Recommanded Product: Ethyl 4-pyrazolecarboxylate, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, 37622-90-5.

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics

Pyrazoles can be selectively lithiated at different carbons and subsequently react with electrophiles depending on the substitution patterns. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. 1-Methyl-5-(trifluoromethyl)pyrazole underwent deprotonation and subsequent carboxylation mainly or exclusively at either the 4-position of the heterocycle or at the nitrogen-attached methyl group. Category: pyrazoles-derivatives.

Li, Xiangqiang;Guo, Jing;Lin, Lili;Hu, Haipeng;Chang, Fenzhen;Liu, Xiaohua;Feng, Xiaoming research published 《 Chiral Magnesium(II) Complex-Catalyzed Enantioselective Desymmetrization of meso-Aziridines with Pyrazoles》, the research content is summarized as follows. A highly enantioselective catalytic protocol for the desymmetrization of meso-aziridines via ring-opening with pyrazoles was reported using an N,N’-dioxide-Mg(OTf)₂ complex as the catalyst. The corresponding trans-α-pyrazole-substituted amines were obtained in good yields and enantioselectivities (up to 99% yield and 94% ee) under mild reaction conditions. Moreover, a remarkably high asym. amplification was observed in the catalytic system.

37622-90-5, Ethyl 4-pyrazolecarboxylate, also known as Ethyl pyrazole-4-carboxylate, is a useful research compound. Its molecular formula is C6H8N2O2 and its molecular weight is 140.14 g/mol. The purity is usually 95%.

Ethyl pyrazole-4-carboxylate is a low yield, transition metal salt that is used in the synthesis of pyrazoles. It can be synthesized by the reaction of sodium ethoxide with ethyl chloroformate and a Grignard reagent. Sodium ethoxide is added to a suspension of sodium chloride and dried ethyl chloroformate, followed by addition of magnesium turnings. The mixture is refluxed for one hour, cooled, and filtered to give crystals. Ethyl pyrazole-4-carboxylate is used in the preparation of ethyl esters from aliphatic alcohols by reacting with boron trichloride or phosphorus pentachloride. It participates in certain chemical reactions as a byproduct and can damage equipment during chemical reactions. The yield of this compound can be increased by using an excess amount of Grignard reagent or adding hexamethylenetetramine to the reaction mixture, Category: pyrazoles-derivatives

Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics