405316-32-7Relevant academic research and scientific papers
Introduction of a novel reaction of triacetylmethane: One-pot synthesis of dialkyl-2-(3,1-hydroxyethylidene-2,4-pentanedione-3-yl)-3-(triphenyl phosphoranylidene)-butanedioate
Shaabani, Ahmad,Bazgir, Ayoob,Teimouri, Mohammad Bagher,Bijanzadeh, Hamid Reza
, p. 833 - 839 (2002)
Protonation of reactive 1:1 intermediates produced in the reaction between triphenylphosphine and dialkyl acetylenedicarboxylate by 3-(1-hydroxyethylidene)-2,4-pentanedione leads to vinyl phosphonium salts, which undergo Michael addition with the conjugate base of CH-acid to produce the title compounds in high yield.
The reaction of phenylhydrazine with sterically congested stabilized phosphorus ylides in the presence of silica gel powder in solvent-free conditions: A novel synthesis of fully substituted pyrazole derivatives
Noshiranzadeh, Nader,Ramazani, Ali
scheme or table, p. 1109 - 1115 (2009/04/07)
Reactions of sterically congested stabilized phosphorus ylides with phenylhydrazine in the presence of silica gel powder in solvent-free conditions proceed smoothly at 100°C to afford dialkyl 2-(3,5-dimethyl-1-phenyl-1H- pyrazol-4-yl)-2-butenedioates in good yields. The structures of the products were deduced from their IR, 1H NMR, and 13C NMR spectra. The mass spectra of these compounds displayed molecular ion peaks at the appropriate z values. The 1H NMR (CDCl3) spectra of the compounds show the presence of two estereoisomers (E and Z) for each pyrazoles. The relative population of E and Z isomers were determined via their 1H NMR spectra The reaction is fairly stereoselective. Copyright Taylor & Francis Group, LLC.
