Oxidation of Olefins with Hydrogen Peroxide Catalyzed by Bismuth Salts: A Mechanistic Study

Abstract

Theoretical (DFT) calculations predict that soluble Bi salts exhibit catalytic activity toward oxidation of olefins with H2O2. Reaction occurs via two competitive channels: (i) nonradical epoxidation of the CC double bond and (ii) radical hydroperoxidation of the allylic C atom(s) with involvement of the HO• radicals, realized concurrently and leading to epoxide/diol and alkenylhydroperoxide products, respectively. The most plausible mechanism of epoxidation includes the substitution of a water ligand in the initial Bi aqua complex, hydrolysis of the coordinated H2O2, one-step oxygen transfer through a direct olefin attack at the unprotonated O atom of the OOH– ligand in [Bi­(H2O)5(OOH)]2+, and liberation of the epoxide from the coordination sphere of Bi. The main conclusions of the theoretical calculations were confirmed by preliminary experiments on oxidation of cyclohexene, cyclooctene, and 1-octene with the systems Bi­(NO3)3/H2O2/CH3CN + H2O and BiCl3/H2O2/CH3CN + H2O.

New Trends in Oxidative Functionalization of Carbon–Hydrogen Bonds: A Review

“…According to DFT calculations, H 2 O 2 molecule in complex 4 is highly activated toward the homolysis in the free hydrogen peroxide (6.1 vs. 39.4 kcal/mol). This approach has been used for some other non-transition metals [163][164][165][166][167]. The overall activation barriers (kcal/mol) of the generation of hydroxyl radicals were calculated: Ga (19. with Fe(II) or a Fenton-like reaction (for example with Fe III ), a transition metal can change its oxidation state (Fe II Fe III ) in the course of the hydrogen peroxide decomposition.…”

Deep eutectic solvents (Reline) and Gold Nanoparticles Supported on Titanium Oxide (Au–TiO2) as New Catalysts for synthesis some substituted phenyl(substituted-3-phenyloxiran)methanone Enantioselective Peroxidation

“…Later, the olefinic double bond with various oxidizing agents was successfully oxidized via the reaction of arylidene tetralones with Egyptian Journal of Chemistry http://ejchem.journals.ekb.eg/ hydrogen peroxide in a basic medium. The reaction involved formation of an intermediate via addition of 1,4 in the first step, followed by intramolecular cyclization of the intermediate to form the final product of keto oxiranes in good yield [5]. Moreover, a novel series of biphenyl keto oxiranes have been synthesized using sodium hypochlorite, which have been evaluated as antimicrobial and insect antifeedant activities of all synthesized oxiranes [6].…”

One Pot and Two Pot Synthetic Strategies and Biological Applications of Epoxy-Chalcones

“…Epoxide is commonly employed as a precursor for the synthesis of various active compounds via ring opening reaction [2]. Several synthetic methodologies have been reported for the preparation of epoxide namely Johnson-Corey-Chaykovsky epoxidation [3], Sharpless epoxidation [4,5] olefin peroxidation [6], dehydrohalogenation [7] and Jacobsen-Katsuki epoxidation [8].…”