Introduction The fatty acid esters synthesis by transesterification of oils to produce biodiesel commonly involves methanol or ethanol as acyl acceptor. The transesterification of vegetable oils catalyzed by lipases is an alternative process for obtaining biodiesel. These biocatalysts working under mild conditions of temperature, allow for easy recovery of glycerol, synthesis of specific alkyl ...

HIV-1 integrase is the viral enzyme responsible for the insertion of the viral DNA into the host cell chromosome. This process occurs through two distinct biochemical reactions: the 30-processing of the viral DNA and the transesterification reaction. Because experimental structural information on the reaction intermediate is not available, several molecular models have been developed. Unfortuna...

A supercritical methanol transesterification method was applied to produce biodiesel from the high-acid oil of soybean soapstock. The fuel properties of biodiesel produced with various molar ratios of methanol to raw oil were analyzed and compared in this experimental study. Oleic acid (C18:1), linoleic acid (C18:2), and palmitic acid (C16:0) were the three main compounds in the high-acid oil-b...

The synthesis of fatty acid ethyl ester from chicken fat waste using ZnO/SiO2 heterogeneous catalyst was carried out using two-step procedures of acid pretreatment by esterification and transesterification of the pretreated oil. The first step reduces the high free fatty acid in the oil to an acceptable level for transesterification using concentrated sulphuric acid at a temperature of 60 oC du...

Sulphated zirconia, one of the most efficient solid acid catalysts, has been explored in present studies for transesterification reaction. The catalyst was synthesized by conventional precipitation method and characterized XRD, TGA, FTIR total acidity. exhibits excellent activity model triglyceride triacetin as well Jatropha oil with high selectivity towards formation monoalkyl esters. Influenc...

A method has been developed for the conversion of primary, secondary, and tertiary alcohols, and phenol, into the corresponding esters at room temperature. The method uses a titanium(III) species generated from a substoichiometric amount of titanocene dichloride together with manganese(0) as a reductant, as well as methylene diiodide. It involves a transesterification from an ethyl ester, or a ...

The choice is yours: a highly stereoselective synthesis of α-alkyl-α-hydroxy-β-amino esters is accomplished through a tandem Wittig-rearrangement/Mannich reaction sequence. Transformations of N-benzyl or N-Boc imines proceed with high selectivity for formation of syn-amino alcohol derivatives, whereas N-Boc-2-(phenylsulfonyl)amines generate anti-amino alcohol products. Auxiliary cleavage (trans...

We have designed a new hypercrosslinked supermicroporous polymer (HMP-1) with a BET surface area of 913 m(2) g(-1) by FeCl3 via a catalyzed Friedel-Crafts alkylation reaction between carbazole and α,α'-dibromo-p-xylene. Upon sulfonation HMP-1 yielded a very efficient solid acid catalyst for the production of biodiesels via esterification/transesterification of free fatty acids (FFA)/esters at r...

A dynamic resolution process based on multiple reversible cyanohydrin formation coupled to lipase-mediated transesterification is demonstrated. The resulting process resulted in the efficient evaluation of complex lipase performances in asymmetric cyanohydrin acylate synthesis. Dynamic systems were generated and resolved in situ, and the effects of the reaction conditions could be directly moni...

To advance the realization of algae as a feedstock for biodiesel, process technologies and closed-loop biomass use must be optimized. Life-cycle analysis (LCA) of the biodiesel production process highlights the potential significant impact of improvements in the extraction of algal lipids and conversion into biodiesel. Further, a single-step lipid extraction and transesterification process was ...