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. SDS of cas: 37622-90-5.
Guan, Zhipeng;Zhu, Shuxiang;Yang, Yankai;Liu, Yanlong;Wang, Siyuan;Bu, Faxiang;Cong, Hengjiang;Alhumade, Hesham;Zhang, Heng;Lei, Aiwen research published 《 Electrochemically selective double C(sp2)-X (X = S/Se, N) bond formation of isocyanides》, the research content is summarized as follows. The current study demonstrates the C(sp2)-S/Se and C(sp2)-N bond formation of one carbon of isocyanides RNC (R = t-Bu, cyclohexyl, 2,6-dimethylphenyl, etc.) with thiophenols R1SH (R1 = Ph, 2-methoxyphenyl, 3-bromophenyl, etc.) or disulfides or diselenides R2XXR2 (R2 = Me, cyclopentyl, benzyl, etc.; X = S, Se) and azazoles R3H (R3 = 1H-benzo[d][1,2,3]triazol-1-yl, 1H-pyrazol-1-yl, 1H-tetrazol-1-yl, etc.) simultaneously. The reported findings could provide access to novel multiple isothioureas RN=C(SR1/R2)(R3), especially hitherto rarely reported selenoureas RN=C(SeR2)(R3). The protocol showed good atom-economy and step-economy with only hydrogen evolution and theor. calculations accounted for the stereoselectivity of the products. Importantly, the electrochem. reaction could exclusively occur at the isocyano part regardless of the presence of susceptible radical acceptors, such as a broad range of arenes and alkynyl moieties, even alkenyl moieties.
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