CATALYTIC DIMERIZATION OF METHYL ACRYLATE UNDER SUPERCRITICAL CARBON DIOXIDE-IONIC LIQUID BIPHASIC MEDIUM

摘要

The palladium-catalyzed dirnerization of methyl acrylate was conducted under biphasic conditions composed of the ionic liquid 1-n-butyl-3-methylimidazolium tetrafluoroborate and of supercritical CO_2. The selectivity obtained for the tail-to-tail dimers is very high (>98%) as under monophasic conditions, i.e. in the absence of dense CO_2. The activity of the catalyst is also equivalent. Solubility determination of methyl acrylate and the dimers shows that they are highly soluble in the CO_2 phase. These results open up the possibility to run the reaction continuously with the concomitant removal of the products by employing two "greener" solvents.