Pyrazoles are synthesized by the reaction of α,β-unsaturated aldehydes with hydrazine and subsequent dehydrogenation. 37622-90-5, formula is C6H8N2O2, Name is Ethyl 4-pyrazolecarboxylate. Substituted pyrazoles are prepared by condensation of 1,3-diketones with hydrazine (Knorr-type reactions). For example, acetylacetone and hydrazine gives 3,5-dimethylpyrazole. SDS of cas: 37622-90-5.
Liu, Shaohua;He, Peixin;Tian, Zhaofu;Li, Xiaolan;Xu, Chunping research published 《 Ultrasound-assisted extraction and characterization of polysaccharide from Maryland tobacco leaves》, the research content is summarized as follows. Ultrasound-assisted extraction (UAE) of polysaccharide from Maryland tobacco leaves was studied by response surface methodol. Furthermore, the crude polysaccharide was purified and two components (Fr-I and Fr-II) were obtained. FT-IR spectral anal. of the purified polysaccharide revealed prominent characteristic groups. The monosaccharide composition anal. by gas chromatog.-mass spectrometry (GC/MS) indicated the main composition between Fr-I and Fr-II was different. Furthermore, thermo gravimetric anal. (TGA) indicated the degradation temperature (Td) of the Fr-I (241 °C) was higher than those of Fr-II (216 °C). Detected by the pyrolysis gas chromatog.-mass spectrometry (py-GC/MS), it was found that the main kinds of pyrolysis products from both Fr-I and Fr-II were similar. Finally, On the basis of hydroxyl and DPPH radical scavenging assay, Fr-II has stronger antioxidant activities than Fr-I. The thermal behavior and antioxidant activity might be attributed to the configuration of the chem. compositions
SDS of cas: 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, 37622-90-5.
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics