A series of metalloporphyrin dimers were modularly prepared and shown to catalyze the methanolysis of a phosphate triester, yielding rates that are large compared to the rate of the uncatalyzed reaction. Up to 1300-fold rate acceleration can be achieved via a combination of cavity-localized Lewis-acid activation and methoxide-induced methanolysis.

Cell-free extracts of the unicellular red alga Cyanidium caldarium catalyze the transformation of biliverdin to a product indistinguishable from phycocyanobilin, the free bilin derived from phycocyanin by methanolysis. Crude cell-free extract requires biliverdin as the only substrate, but after removal of low molecular weight components by gel filtration, the reaction shows an additional requir...

Methanolysis of intervertebral disc samples at 600 was largely hydrolysis as shown by the absence of methylated derivatives on chromatograms of the reaction products. Extent of the reaction increased with acid strength; the products were the same. Maximum solubilization was about 80% and 50% for hyaline cartilage plate and nucleus pulposus samples, respectively. The results of aqueous acid (hyd...

In this study, catalysts for fatty acid methyl esters (FAME or biodiesel) synthesis with K2CO3 as the active component on an alumina/silica support were synthesized using the sol–gel method, which was followed by drying the “dense” wet gels with supercritical carbon dioxide to obtain the aerogels. The prepared catalysts were characterized by XRD analysis, FTIR spectroscopy and N2 physisorption ...

Triphosgene was decomposed quantitatively to phosgene by chloride ion. The reaction course was monitored by IR spectroscopy (React-IR), showing that diphosgene was an intermediate. The methanolysis of triphosgene in deuterated chloroform, monitored by proton NMR spectroscopy, gave methyl chloroformate and methyl 1,1, 1-trichloromethyl carbonate in about a 1:1 ratio, as primary products. The rea...

The conversion of end-of-life plastics to useful chemicals can contribute a resource-conserving and environmental-benign society. In this regard, we studied the depolymerization via methanolysis poly(1,2-propylene carbonate) using straightforward metal salts as precatalysts. more detail, in presence catalytic amounts Zn(OAc)2 or NaOAc methanol 1,2-propylene carbonate (generated by ring closing ...

A combination of Novozym 435-catalyzed methanolysis and amidation using racemic N-methyl-5-acetoxytridecan- and tetradecanamides as a substrate proceeded in good enantioselectivity to afford the corresponding (R)-N-methyl-5-acetoxyalkanamides, (S)-N-methyl-5-hydroxyalkanamides, and (S)-N-cyclohexyl-5-hydroxyalkanamides. Both enantiomers of δ-tri- and δ-tetradecalactones were synthesized in over...

the present study has been focused on the acid and base transesterification of animal fats (dairy cow and beef) to produce biodiesel by varying process parameters such as catalyst amount, catalyst nature, reaction time and temperature. the maximum biodiesel yield after acid catalysis was 94.1 ± 2.43 and 98.4 ± 2.3 percent for dairy cow and beef tallow, respectively. the quantity of biodiesel ob...

Primary and secondary kinetic and equilibrium isotope effects are calculated with density-functional methods for the dianionic methanolysis of the native (unsubstituted) and thio-substituted ethylene phosphates.

o-Nitrobenzenesulfenamides (1) undergo acid-catalyzed methanolysis (eq 2) in acetonitrile-methanol, affording methyl o-nitrobenzenesulfenate (2). They also undergo acid-catalyzed reaction with a thiol, giving an alkyl o-nitrophenyl disulfide (eq 3). In MeCN-8.2 M MeOH the thiolysis reaction exhibits a simple fmt-order dependence on both [R'SH] and [H+] for acid concentrations in the range 0.001...