15619-54-2

Upstream product

• 90466-74-3 C₁₀H₁₉O₂ 
• 75-91-2 tert.-butylhydroperoxide 
• 110-83-8 cyclohexene 
• 108-85-0 1-bromocyclohexane 
• 56375-24-7 1-Bromo-2-tert-butylperoxy-cyclohexane 
• 2372-21-6 OO-tert-butyl O-isopropyl monoperoxycarbonate 
• 110-82-7 cyclohexane 
• 187939-66-8 1-tert-butylperoxy-3,3-dimethyl-1H-1,2-benziodoxole 
• 14976-54-6 di-tert-butoxydiazene 

Relevant academic research and scientific papers

Highly selective cycloalkane oxidation in water with ruthenium nanoparticles

Ruthenium(0) nanospecies, with small sizes of approximately 1.75 nm, proved to be active, selective, and retrievable nanocatalysts for the oxidation of various cycloalkanes in neat water, using tert-butylhydroperoxide as an oxidant and at room temperature. Relevant conversions and selectivities (up to 97 %) were achieved towards the major formation of the ketone product, which constitutes a high-value-added intermediate for polymer or fine chemistry. The lifetime of the catalyst has been checked over several runs, with no significant loss of activity and selectivity. Kinetic and mechanistic investigations proved that radical species are involved in the oxidation process. A literature comparison showed the relevance and the usefulness of the present ruthenium nanocatalytic system in a benign reaction context. Active, selective, and retrievable! A sustainable oxidation process of cycloalkanes to the ketones with an easy-to-handle and reusable catalyst, in neat water, and under ambient conditions is described. The active catalyst is a ruthenium(0) nanospecies. t-BHP=tert-butylhydroperoxide.

Oxidation of cyclohexane using a novel RuO2-zeolite nanocomposite catalyst

We report the synthesis, using an organic-template-free hydrothermal crystallization method, and catalysis of a new type of nanocomposite material, 1.3 nm-sized RuO2 particles confined in faujasite zeolite. The zeolite-confined RuO2 composites were fully characterized with X-ray powder diffraction, Ru K-edge X-ray absorption, and high-resolution transmission electron microscopy. XRD and X-ray fluorescence analysis indicate that the framework is faujasite zeolite with a Si:Al ratio of 1.25. Ru K-edge X-ray absorption near-edge structures indicate that the ruthenium species in the zeolite is Ru(IV) with nearest-neighbor octahedral environments similar to hydrous RuO2, i.e., distorted RuO6 . The k 2-weighted extended X-ray absorption fine structure indicates ithat the Ru(IV) species anchored in the zeolite likely form amorphous RuO 2 with a 2D-chain structure, in which RuO6 units are connected together by two shared oxygen atoms. TEM shows that the particle size of RuO2 encapsulated inside the supercages of FAU is about 1.3 nm. The RuO2-FAU composites display significant catalytic activity in the oxidation of cyclohexane with tBHP under mild (room temperature and 1 atm (1 atm ≡ 101.325 kPa)) conditions. The ketone and alcohol concentration can be as high as 0.26 mol L-1 in 5 h with 48% peroxide efficiency. The catalyst is stable and reusable. Possible oxidation mechanisms are also discussed.

Selective oxidation of cyclohexane to cyclohexanol catalyzed by a μ-hydroxo diiron(II) complex and tert-butylhydroperoxide

A new μ-hydroxo diiron(II) complex [Fe2L(OH)]3+ obtained with a dinucleating macrocyclic ligand catalyzes the selective oxidation of cyclohexane into cyclohexanol (≈85%) using the controlled addition of tert-butylhydroperoxide.

Cyclohexane Functionalization Catalyzed by Octahedral Molecular Sieve (OMS-1) Materials

Both the abundance of alkanes and their extremely low activity have greatly interested several researchers. In this paper, different metal substituted 3×3 octahedral molecular sieves (OMS-1) materials were used to catalyze the functionalization of cyclohexane by using tert-butyl hydroperoxide as oxidant and tert-butyl alcohol as solvent at different temperatures (60, 80, and 100°C). [Fe]-OMS-1 at 80°C exhibits the best activity and selectivity. The solvent t-butyl alcohol (the reduced state of t-butyl hydroperoxide) was first introduced to the reaction system which makes the system simple to study. The effects of catalyst amount and ratio of tert-butyl alcohol to cyclohexane were examined. Variable speed stirring (200-800 rpm) experiments suggest that under conditions reported here that diffusion is not a problem. Studies of the liquid phase after separation from the solid OMS-1 catalysts have shown that metal does not leach into the solution and that heterogeneous catalysis occurs. At 80°C, the conversion of cyclohexane or the total yield of products can reach 13.1% in 40 h. The yields of cyclohexanone, cyclohexanol, and cyclohexyl hydroperoxide were 6.57,2.83, and 1.38%, respectively, and t-butyl cyclohexyl perether was 2.36%. The reaction conditions are mild, and the catalysts retain their crystallinity after reaction. Moreover, the catalyst can be easily separated from the reaction mixture and used catalysts retain similar catalytic activity over a 40-h time period.

Ruthenium colloids: A new catalyst for alkane oxidation by tBHP in a biphasic water-organic phase system

Efficient and highly selective conversion of cyclooctane into cyclooctanone is obtained under pure biphasic conditions through t-butylhydroperoxide activation by the in situ formation of colloidal ruthenium species arising from RuCl3, 3H2O. Model extension experiments to other cycloalkanes are also discussed.

Evidence for divalent iodine (9-I-2) radical intermediates in the thermolysis of (tert-butylperoxy)iodanes. An unusually efficient deiodination of o-iodocumyl alcohols by cyclohexyl radicals

1-(tert-Butylperoxy)-3,3-dimethyl-1H-1,2-benziodoxoles (2a and 2b) and 1-(tert-butylperoxy)-3,3-bis(trifluoromethyl)-5-methyl-1H-1,2-benziodo xole (2c) were prepared from chloroiodanes 1a-c and tert-butylhydroperoxide in the presence of potassium tert-butoxide in tetrahydrofuran. Products, kinetic data for the decomposition of 2 in cyclohexane, benzene, toluene, and acetonitrile (E(a) = 31.0 ± 1.0 kcal/mol, log A = 17.0 ± 0.5; 35-70 °C), and the increased rate of decomposition of 2c in benzene-d6 in the presence of a magnetic field (7 T) indicate that homolytic cleavage of the I-O bond in 2 with the formation of iodanyl (9-I-2) and tert-butylperoxyl radicals is the primary decomposition step. The nearly quantitative formation of iodocyclohexane during the decomposition of 2c in cyclohexane is due to the unexpected reaction of cyclohexyl radicals with 2-(2-iodo-5-methylphenyl)-1,1,1,3,3,3-hexafluoro-2-propanol, a primary decomposition product of 2c. The results of a separate study of the deiodination of o-iodocumyl alcohols (3) by cyclohexyl radicals are consistent with an S(H)2 type mechanism.

Oxygen activation by metal complexes and alkyl hydroperoxides. Applications of mechanistic probes to explore the role of alkoxyl radicals in alkane functionalization

The mechanism of the oxidation of cycloalkanes by tertiary alkyl hydroperoxides catalysed by iron(III) dichlorotris(2-pyridylmethyl)amine IIICl2(TPA)>+ and by the acetate bridged (μ-oxo) di-iron complex III(TPA)2O(OAc)>3+ has been investigated.Product studies do not support oxidation via a high valent iron-oxo intermediate (formally FeV=O), but are consistent with a mechanism involving hydrogen atom abstraction from the alkane by alkoxyl radicals derived from the hydroperoxide.In the presence of a large excess of tert-butyl hydroperoxide, the oxidation of cyclohexane yields cyclohexanone, cyclohexanol and tert-butylcyclohexyl peroxide in more than stoichiometric amounts and, in the case of the mono-iron catalyst, one equivalent of cyclohexyl choride.Replacement of Me3COOH by hydroperoxides, which could yield tert-alkoxyl radicals having much shorter lifetimes than the tert-butoxyl radical prevents oxidation of the cycloalkane.The products obtained with these hydroperoxide mechanistic probes are those derived from the fast unimolecular reactions (generally β-scissions) of the corresponding alkoxyl radicals.The inapplicability of dimethyl sulfide as a mechanistically diagnostic trap for the putative FeV=O intermediate and the value of di-tert-butyl hyponitrite as a non-iron-based source of tert-butoxyl radicals are discussed.

A putative monooxygenase mimic which functions via well-disguised free radical chemistry

The hydroxylation of cycloalkanes at 25°C by the syringe pump addition of tert-alkyl hydroperoxides (10 and 1 equiv based on catalyst) to deoxygenated acetonitrile containing cycloalkanes (0.64 M) and 0.61 mM of the catalyst, [Fem(III)2O(TPA)2(H2O)2]4+, is demonstrated to be a reaction which involves freely diffusing cycloalkyl radicals, i.e., free alkyl radicals.

Fe(TPA)-catalyzed alkane hydroxylation. Metal-based oxidation vs radical chain autoxidation

Catalytic alkane functionalization by the Fe(TPA)/(t)BuOOH system (with [Fe(TPA)Cl2]+ (1), [Fe(TPA)-Br2]+ (2), and [Fe2O(TPA)2(H2O)2]4+ (3) as catalysts; TPA = tris(2-pyridylmethyl)amine) has been investigated in further detail to clarify whether the reaction mechanism involves a metal- based oxidation or a radical chain autoxidation. These two mechanisms can be distinguished by the nature of the products formed, their dependence on O2 (determined from argon purge and 18O2 labeling experiments), and the kinetic isotope effects associated with the products. The metal-based oxidation mechanism is analogous to heme-catalyzed hydroxylations and would be expected to produce mostly alcohol with a large kinetic isotope effect. The radical chain autoxidation mechanism entails the trapping of substrate alkyl radicals by O2 to afford alkylperoxy radicals that decompose to alcohol and ketone products in a ratio 1:1 or smaller via Russell termination steps. Consistent with the latter mechanism, alcohol and ketone products were observed in a ratio of 1:1 or less, when catalysts 1, 2, or 3 were reacted with alkane and 150 equiv of (t)BuOOH; these product yields were diminished by argon purging, demonstrating the participation of O2 in the reaction. However, when the 3-catalyzed oxidation was carried out in the presence of a limited (20 equiv) amount of (t)BuOOH or CmOOH, the sole product observed was alcohol; k(H)/k(D) values of 10 were observed, consistent with a metal- based oxidation. To reconcile these apparently conflicting results, a mechanistic scheme is proposed involving the formation of an alkylperoxyiron(III) intermediate which can oxidize either the substrate (metal-based oxidation) or excess ROOH (to generate alkylperoxy radicals that initiate a radical chain autoxidation process), the relative importance of the two mechanisms being determined by the concentration of ROOH.

Manganese(II) based Oxidation of Alkanes: Generation of a High Valent Binuclear Catalyst in situ

The efficiently Mn2+ -catalysed oxidation of saturated hydrocarbons by alkylhydroperoxides or iodosylbenzene in the presence of 2,2'-bipyridine in acetonitrile follows the following pathway: Mn2+ + bipy -> 2+ -> 3+, the latter being identified as the catalytic species; it affords cyclohexanol and cyclohexanone in equal amounts and the remarkable robustness of the active complex, under oxidative conditions, is noted.