Lewis acidic ionic liquids for the synthesis of electrophilic alkenes via the Knoevenagel condensation
作者:Jitendra R Harjani、Susheel J Nara、Manikrao M Salunkhe
DOI:10.1016/s0040-4039(01)02341-3
日期:2002.2
[bpy]Cl·AlCl3, N=0.67 ionic liquids were found to work well as the Lewis acid catalyst and solvent in the Knoevenagelcondensations of benzaldehyde and substituted benzaldehydes with diethylmalonate to give benzylidene malonates. The benzylidene malonates subsequently underwent Michael additions with diethylmalonate. The extent of Michael product formed during the reaction was found to vary with the Lewis acidity
Tandem Knoevenagel−Michael Addition of Aryl Sulfonimines with Diethyl Malonate for Synthesis of Arylidene Dimalonates
作者:Renhua Fan、Weizi Wang、Dongming Pu、Jie Wu
DOI:10.1021/jo070726e
日期:2007.7.1
A highly efficient, one-flask tandem Knoevenagel-Michael addition reaction of sulfonimines with diethyl malonate in the presence of a catalytic amount of base affords the corresponding arylidene dimalonates in good to excellent yields.
Determination of the Electrophilicity Parameters of Diethyl Benzylidenemalonates in Dimethyl Sulfoxide: Reference Electrophiles for Characterizing Strong Nucleophiles
作者:Oliver Kaumanns、Roland Lucius、Herbert Mayr
DOI:10.1002/chem.200801277
日期:2008.10.29
second-order rate constants of the reactions of nine substituted diethyl benzylidenemalonates 1 a-i with the carbanions 2 a-e have been determined spectrophotometrically in dimethyl sulfoxide (DMSO). Product studies show that the nucleophiles attack regioselectively at the electrophilic C==C double bond of the Michael acceptors to form the carbanionic adducts 4. The correlation log k(20 degrees C)=s(N+E) allows