Free-solvent Michael addition of glycerol to acrylic compounds†
Abstract
In this paper, we report the study of the free-solvent nucleophilic addition of alcohols and glycerol to acrylic compounds, in the presence of catalytic bases. With acrylates, Michael addition and transesterification are in competition: only the PTC reaction with t-butyl acrylate gave trifunctionalized glycerol. With acrylonitrile, the cyanoethylation of glycerol varies with catalysts, temperature, time of reactions and amounts of acrylonitrile. Mono functionalisation of glycerol can be obtained in 28% yield. The optimization of the free-solvent Michael addition of glycerol to acrylonitrile (3.4 equiv., 4 mol% NaOH, 5 h) leads to TCEG (tricyanoethylglycerol, 88% yield, 99% purity) without HCl neutralisation, chlorinated solvents or purification (chromatography or distillation). TCEG can be used as a prochiral core of G0.5 dendrimers.