Osmium impregnated on magnetite as a heterogeneous catalyst for the syn-dihydroxylation of alkenes

Abstract

Easy preparation of a novel magnetic nanocatalyst.Simple catalyst removing by an external magnetic field. The lowest catalyst loading reported for this transformationThe use of complicated and expensive organic ligands, used in related processes, is avoided AbstractA new catalyst derived from osmium has been prepared, fully characterized and tested in the dihydroxylation of alkenes. The catalyst was prepared by wet impregnation methodology of OsCl 3 •3H 2 O on a commercial micro-magnetite surface. The catalyst allowed the reaction with one of the lowest osmium loadings for a heterogeneous catalyst and was selective for the monodihydroxylation of 1,5-dienes. Moreover, the catalyst was easily removed from the reaction medium by the simple use of a magnet. The selectivity of catalyst is very high with conversions up to 99%. Preliminary kinetics studies showed a first-order reaction rate with respect to the catalyst.

ChemInform Abstract: Magnetite and Metal‐Impregnated Magnetite Catalysts in Organic Synthesis: A Very Old Concept with New Promising Perspectives

“…Unfortunately,a fter the magnetic separation, the catalyst could not be successfully reused again. [95] Ap ossible explanation was the lack of OsO 2 (OH) 2 in the recycled catalystf ound by the XPS study,b eing presenti n a1:1 ratio on the fresh sample. Os VI may be the active catalytic species.…”

Magnetite and Metal‐Impregnated Magnetite Catalysts in Organic Synthesis: A Very Old Concept with New Promising Perspectives

“…Only 0.08 mol % of catalyst loading was required to carry out the reaction depicted in Scheme . Unfortunately, after the magnetic separation, the catalyst could not be successfully reused again . A possible explanation was the lack of OsO 2 (OH) 2 in the recycled catalyst found by the XPS study, being present in a 1:1 ratio on the fresh sample.…”

Similarities and Differences for Atomic and Diatomic Molecule Adsorption on the B-5 type sites of the HCP(1016) surfaces of Co, Os, and Ru from DFT Calculation

“…Cobalt is an active catalyst for reactions such as Fischer-Tropsch (FT) synthesis and Dry Reforming of CH 4 , Osmium a relatively mediocre catalyst for alkene hydroxylation and the Haber-Bosch reaction and a good doping/alloying agent in making intermetallic Oxygen Reduction Reaction (ORR) catalysts, and Ruthenium an active catalyst for FT synthesis, Haber-Bosch and recently in biofuels conversion. [7][8][9][10][11][12][13][14][15][16] Despite the fact these materials have been used and researched for such catalytic applications for decades, only recently has there been a large uptick in research related to understanding exact atomic mechanisms for their catalytic properties via the step and edge sites that their nanoparticles possess. [8,[17][18][19][20][21][22][23][24][25][26][27][28] Previous computational and theory studies of the adsorption energies and catalytic properties of Co,Os, and Ru materials have typically relied on using over-simplified surface models of the step sites that HCP catalyst nanoparticles of these elements possess.…”