Esterification Of 1-butanol Research Articles

Hyperbranched vs. linear polymers in the catalysis by sulfonic acid functionalized poly(ether sulfone)

Aromatic hyperbranched polymers, such as hyperbranched poly(ether sulfone), are promising catalytic materials, but the advantages of the hyperbranched structure have not been well understood. In this study, hyperbranched poly(ether sulfone), functionalized with sulfonic acid terminal groups (HBSPES) and its linear analogue (LSPES), were studied as acid catalysts for a model reaction, namely, the esterification of 1-butanol and acetic acid. In the homogeneous catalytic reaction, HBSPES showed a clear advantage in the apparent turnover frequency (TOF). To utilize these polymers as heterogeneous catalysts, they were immobilized onto carbon black (CB) to obtain HBSPES/CB and LSPES/CB. The polymer loading after immobilization was higher with HBSPES/CB, probably due to the dense architecture of the hyperbranched polymer. In the heterogeneous catalytic reaction, HBSPES/CB exhibited a much better catalytic performance than LSPES/CB, possibly benefiting from the good affinity of the hyperbranched polymer to the reaction solution. These experimental observations suggest that aromatic hyperbranched polymers are suitable for use as catalysts.

Intital water content and lipase-mediated ester formation in hexane

Lipase biocatalysis was investigated as a tool for the production of esters by two model reactions, esterification of 1-butanol with 2-methyl-1-pentanoic acid and irreversible transesterification between 2-methyl-1-pentanol and vinyl acetate. The reactions were carried out in hexane using lipases from Candida cylindracea and porcine pancreas. The initial water content influenced both the yield of the ester and the enantioselectivity of the reaction (esterifica-tions) or the ester formation only (transesterifications).