Synthesis of 3-substituted and 3,4-disubstituted pyrazolin-5-ones

Add time:08/06/2019    Source:sciencedirect.com

The synthesis of 3-substituted and 3,4-disubstituted pyrazolin-5-ones from acylated ethyl acetoacetates and diethyl malonates is described. The reaction of acylated ethyl acetoacetates and diethyl acetylmalonate with hydrazine (98%) gave 3-substituted pyrazolin-5-ones and malonyldihydrazide, respectively, following a deacetylation–condensation sequence. The reaction of ethyl 2-acetyl-3-hydroxy-2-butenoate and diethyl 2-(1-hydroxyethylidene)malonate with hydrazine monohydrochloride yielded ethyl 3,5-dimethyl-1H-pyrazole-4-carboxylate and 4-ethoxycarbonyl-3-methylpyrazolin-5-one, respectively, following a dehydration–cyclocondensation sequence, in high yields.

We also recommend Trading Suppliers and Manufacturers of 5-(1-Hydroxyethylidene)-2-methyl-1,3-cyclopentadiene-1,3-dicarboxylic acid dimethyl ester (cas 14374-51-7). Pls Click Website Link as below: cas 14374-51-7 suppliers

Prev:Synthesis, spectroscopic and DFT investigation of dimethyl-2-(5-acetyl-2,2-dimethyl-4,6-dioxo-1,3-dioxan-5-yl)-3-(triphenylphosphinylidene)succinate
Next:Bisphosphonate prodrugs: synthesis and in vitro evaluation of alkyl and acyloxymethyl esters of etidronic acid as bioreversible prodrugs of etidronate)