Oxidation of adamantane

Adamantanol has been prepared by oxidation of adamantane with peroxyacetic acetic" and by hydrolysis of 1-bromoadamantane with silver nitrate s or hydrochloric acid. ... 

Kinetics of the dimethyidioxirane oxidation of adamantane in an oxygen atmosphere support a radicai mechanism. The kinetics of the oxidation of 2-methyibutane by DMDO in acetone soiution have been studied and the mechanisms of the reaction and of inhibition of the reaction by O2 were discussed. 

Second-order kinetics for oxidation of adamantane and other hydrocarbons by stoich. RuO /aq. acetone or /aq. CCyCHjCN were demonstrated there is a large deuterium isotope effect, a small enthalpy and a large negative entropy of activation. A two-step mechanism was proposed a pre-equilibrium reaction in which (for the alkene RH), RH + RuO gives RH.RuO which, in a rate-determining concerted reaction, yields R-0-Ru02(0H) which is then aquated to form R(OH) [388] (Fig. 1.10) [389, 390],... 

Fig. 4.2 Oxidation of adamantane to (a) adamant-l-ol (b) adamant-2-ol (c) adamant-1,3-diol (d) adamant-2-one...

It has been also found that PhIO as an oxidant in the presence of a catalytic amount of sulfonated manganese and iron porphyrin supported on poly(vinylpyridinium) polymers in olefin epoxidation and alkane hydroxylation is a better oxidant than Bu4NHS05 °. Oxidation of adamantane to 1-adamantanol in good yield using BU4NHSO5 and acetone in the presence of aqueous NaHCOs was also reported . ... 

Table I. Oxidation of adamantane by PhIO catalyzed by MnCli2TMPS immobilized on different supports ...

It is interesting to note that in a somewhat similar catalytic system consisting of iron powder, acetic acid, and heptanal, aerobic oxidation of adamantane gave 1-adaman-tanol with high selectivity, while cycloalkanes were transformed to ketones as the main products.163... 

Manganese(III) acetate is poorly reactive with saturated hydrocarbons.514 However, oxidation of adamantane by Mn(OAc)3 in trifluoroacetic acid gives relatively high yields of 1-adamantyl trifluoroacetate, showing a preferential attack at tertiary C—H bonds.515 Oxidation of n-alkanes by air in the presence of manganese catalysts constitutes the basis for an industrial process for the manufacture of synthetic fatty acids from n-alkanes of petroleum origin, which has been commercially developed in the Soviet Union.516... 

Alkyl cations thus formed may recombine with the nucleophile (Eq. 10) giving tri-fluoroacetates or acetamides under anodic oxidation conditions in CF3COOH or CH3CN, respectively. For example, electrooxidation of cyclohexane (7) in CH2C12/ CF3COOH yielded 84 % cyclohexyl trifluoroacetate (15) [23] oxidation of adamantane (9) gave acetamide (16) cleanly (Scheme 4) [24]. 

Figure 8.22 Photo-oxidation of adamantane (5a) within cage 2 via guest-host electron transfer.

A dinuclear ruthenium complex with both ruthenium in 2+ oxidation states catalyzes the oxidation of adamantane to hydroxy adamantane and alkene to epoxide by dioxygen. Suggest a possible mechanism. 

Table I. Oxidation of Adamantane with Dioxygen Catalyzed by Fe(Salen)20, 1...

RuCl(dpp)2] /PhIO (or LiClO) [117] are efficient for the oxidation of cyclohexane and adamantane. Ruthenium] 111) complexes such as [RuCl2(TPA)] and [RuCl-(Me2SO)(TPA)] bearing tripodal ligand TPA (TPA = tris(2-pyridylmethyl)amine) were synthesized, and catalytic oxidation of adamantane with m-chloroperbenzoic... 

The oxidation of adamantane occurs almost exclusively at the tertiary carbon, C-1 (equation 51) [106, 545, 546]. 

Oxidation of n-alkanes by Co acetate in acetic acid occurs with a remarkable regioselectivity (rs) at the alkyl acetate as the major product in anaerobic conditions, and 2-alkanone in the presence of oxygen (equations 233 and 234). Cyclohexane is readily oxidized in nitrogen by Co(OAc)3 in acetic acid to mainly cyclohexyl acetate and 2-acetoxycyclo-hexanone. In the presence of oxygen and a high cobalt concentration, adipic acid is the major product formed (equation 235). Oxidation of adamantane by Co(OAc)s and TFA in AcOH preferentially occurs at the tertiary positions, producing 1-adamantyl acetate as the major product. ... 

Table 1. Comparison of reagents for the oxidation of adamantane (1) and decalins 10 and 12.

Manganese(III) acetate is poorly reactive with saturated hydrocarbons. However, oxidation of adamantane by Mn(OAc)3 in trifluoroacetic acid gives relatively high yields of 1-adamantyl... 

The selective oxidation of adamantane to adamantanols with molecular oxygen has found practical application by using NHPI catalysis. The reaction has been proposed and patented by Ishii in collaboration with Daicel Chemical Company [8] and consists of the aerobic oxidation of adamantane in chlorobenzene or acetic acid at temperatures ranging from 75 to 85 °C for 7 h in the presence of 10% mol of NHPI and 0.5% mol of different metal salts, including Co(acac)2, Co(OAc)2, VO(acac)2, and V2O5 (Scheme 16.5). 

Scheme 16.5 Aerobic oxidation of adamantane catalyzed by NHPI.

The chemical (Gif system) and the electrochemical conversion (Gif-Orsay system) have been compared in the oxidation of six saturated hydrocarbons (cyclohexane, 3-ethylpentane, methylcyclopentane, cis- and traus-decalin and adamantane). The results obtained for pyridine, acetone and pyridine-acetone were similar for both systems. Total or partial replacement of pyridine for acetone affects the selectivity for the secondary position and lowers the ratio ketone secondary alcohol. The formation of the same ratio of cis- and traws-decal-9-ol from either cis- or trans-deca in indicates that tertiary alcohols result from a mechanism essentially radical in nature. The C /C ratio between 6.5 and 32.7 rules out a radical mechanism for the formation of ketones and secondary alcohols. Ratios of 0.14 and 0.4 were reported for radical-type oxidations of adamantane and cis-decalin. Partial replacement of pyridine by methanol, ethanol or f-propanol results in diminished yields and a lower selectivity. Acetone gives comparable yields however, the C /C ratio drops to 0.2-10.7. 

The first Gif-Orsay system (Pt-anode, Hg-cathode, cpe, TEABF4 in pyridine-acetic acid, divided cell) converted adamantane to 3.5% 1-adamantanol, 0.7% 2-adamantanol and 3.0% adamantone. Replacement of acetic acid by trifluoroacetic acid and its continuous addition to maintain a constant acidity improved the coulombic yield and selectivity. The oxidation of adamantane yielded 18% product with a C /C ratio of 8.5, this one of cyclodecane 21.1% product, and this one of trans-decalin 22.2% product, with a C /C ratio of 36. The results come close to those obtained in the chemical system. The third system... 

The oxidation of adamantane and other saturated hydrocarbons to ketones by Gif-type systems does not involve secondary adamantyl radicals as the corresponding pyridine adducts 10 and 11 are absent [137,1381 if sufficient 0 is available. This is in support of an... 

So our first e, periment to test our hypothesis was tlie oxidation of adamantane in pyridine with some acetic acid in the presence of iron powder, hydrogen sulfide and o, ygen. Surprisingly, a major amount of adamantanone was formed and there was only minor formation of the tertiary alcohol. Later, we obtained the same results when we replaced the iron powder with zinc powder and added a catalytic amount of an Fe salt. This showed the unusual power of the iron species formed to make ketones as principal products. 

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