Three new chiral Mn macrocycle catalysts containing 20 or 40 atoms in the were synthetized and tested enantioselective epoxidation of cis-β-ethyl-styrene 1,2-dihydronathalene. The effect presence a binaphtol (BINOL) compound catalyst backbone has been evaluated, including by Density Functional Theory (DFT) calculations.

In this paper, we investigate by means of first-principles density functional theory calculations the 111 surface of the Ag-Cu alloy under varying conditions of pressure of the surrounding oxygen atmosphere and temperature. This alloy has been recently proposed as a catalyst with improved selectivity for ethylene epoxidation with respect to pure silver, the catalyst commonly used in industrial ...

Two new heterogenized epoxidation nanocatalysts based on molybdenum and tungsten compounds were prepared withcovalent grafting of MCM-41 with 3-aminoropropyl trimethoxysilane and subsequent reaction with diphenylphosphinobenzaldehyde and complexation with M (Mo, W)O2(acac)2. X-ray diffraction and nitrogen sorption analyses revealed the preservation of the textural properti...

The Fe3O4@SiO2@APTMS@Glu-His@V complex was prepared with modification of iron oxide magnetic nanoparticles with (3-aminopropyl) trimethoxysilane (APTMS) and glutaraldehyde-L-histidine Schiff base followed by complexation with VOSO4. Characterization of the Fe3O4@SiO2@APTMS@Glu-His@V complex was carried out by means of FTIR, XRD, SEM, EDX, TEM, AAS and VSM techniques. It was found that Fe3O4@SiO...

In the area of catalytic asymmetric epoxidation, the highly enantioselective transformation of cyclic enones and quinones is an extremely challenging target. With the aim to develop new and highly effective phase-transfer catalysts for this purpose, we conducted a systematic structural variation of PTCs based on quinine and quinidine. In the total of 15 new quaternary ammonium PTCs, modificatio...

The role played by the additives salicylic acid, L-ascorbic acid and oxalic acid in promoting the catalytic activity of [MnIV2(O)3(tmtacn)2](PF6)2 (1(PF6)2, where tmtacn = N,N',N''-trimethyl-1,4,7-triazacyclononane) in the epoxidation and cis-dihydroxylation of alkenes with H2O2 and in suppressing the catalysed decomposition of H2O2 is examined. Whereas aliphatic and aromatic carboxylic acids e...

The chemo-enzymatic epoxidation of rapeseed methyl ester (RME) in a solvent-free medium was studied using the immobilized Candida antarctica lipase B (Novozym® 435) as catalyst. Hydrogen peroxide (H2O2) was used as the oxygen donor. The enzyme cost is an important factor determining the economics of the process. High enzyme stability and the possibility to recycle the enzyme are therefore highl...

Conversion of unsaturated fatty acids, FAMEs or triglycerides into the corresponding cyclic organic carbonates involves two reaction steps—double-bond epoxidation and CO2 insertion epoxide—that are generally conducted separately. We describe an assisted-tandem catalytic protocol able to carry out carbonation methyl oleate in one-pot without isolating epoxide intermediate. Methyl carbonate was o...