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Manuel Nunes da Ponte

Publications and source records attributed to Manuel Nunes da Ponte.

3 recordsLinked to original sources

Evidence for lower critical solution behavior in ionic liquid solutions.

Lower critical solution temperatures (LCST)-type of phase diagrams, including the presence of closed loops, have been encountered for the first time in binary and quasi-binary liquid solutions of ionic liquids. Furthermore, the results constitute the first experimental support for the existence of a theoretically postulated, but never encountered, special kind of type VII phase diagram. Two distinct mechanisms are involved in the appearance of demixing upon temperature increase. These findings underlie the presence of specific, oriented interactions between the ionic liquid, 1-alkyl-3-methylimidazolium bis{(trifluoromethyl)sulfonyl}amide, [Cnmim][NTf2], and trichloromethane, as well as aggregation phenomena.

Journal Article↗

Clean osmium-catalyzed asymmetric dihydroxylation of olefins in ionic liquids and supercritical CO2 product recovery.

The combination of ionic liquids (ILs) as solvents in the asymmetric Sharpless dihydroxylation (AD) with the use of scCO(2) in the separation process allows a very simple, efficient, clean and robust system for the reuse of the AD catalytic system, which also does not need the use of organic solvents either for the reaction or for the separation of products and allows the isolation of the diol, in high yield and enantiomeric excess and basically without contamination with osmium.

Journal Article↗