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The acylation of the model substrate (R,S)-2-octanol with succinic anhydride catalysed by immobilised Candida antarctica lipase B was studied in two water-miscible organic solvents, two water-immiscible ones, nine 1-alkyl-3-methylimidazolium ionic liquids (RTILs) and two quaternary ammonium RTILs. From previous reports, the reaction was expected to yield an acidic half ester (hemiester). However, it was found that the diester was also produced, in many cases at an even higher yield. The major reaction products were the (R)-hemiester and the (R,R)-diester. In some of the solvents, the amount of hemiester formed increased and then remained constant, whereas in others the amount of hemiester first peaked and then decayed. This behaviour could be explained by the coupling of two reaction pathways: the hydrolysis of the hemiester, and the esterification of the hemiester. The solubility limit of succinic acid, produced in the former pathway, was found to be a discriminating parameter, the precipitation of the acid acting as a driving force for the consumption of the hemiester formed. The impact of the choice of solvent on the outcome of the acylation with succinic anhydride was confirmed by conducting the reaction on a preparative scale: in acetonitrile, the reaction produced 32% (w/w) of (R)-hemiester and 68% (w/w) of (R,R)-diester, whereas in tetrahydrofuran 85% (w/w) of (R)-hemiester and 15% (w/w) of (R,R)-diester were obtained. [ABSTRACT FROM AUTHOR]

We present a new concept for the design of a polymeric conducting material that combines the chemical versatility of an organic salt (ionic liquid) with the morphological versatility of a biopolymer (gelatin); the resulting ‘ion jelly’ can be applied in electrochemical devices, such as batteries, fuel cells, electrochromic windows or photovoltaic cells. [ABSTRACT FROM AUTHOR]

Efficient enzymatic resolution of (±)-cis-benzyl N-(1-hydroxyindan-2-yl)carbamate in [aliq][N(CN)2] by acylation using CALB as a biocatalyst was achieved, with the possibility of catalyst and medium reuse. The reaction proceeds to the formation of the corresponding acetate in moderate yield and high enantiomeric excess for the first and second cycles. Additionally, the biocatalyst can be recovered by filtration and reaction products can be easily removed from the ionic liquid by direct sublimation under high vacuum. [ABSTRACT FROM AUTHOR]