Oxidation adamantanes

The tra x-[Ru (0)2(por)] complexes are active stoichiometric oxidants of alkenes and alkylaro-matics under ambient conditions. Unlike cationic macrocyclic dioxoruthenium I) complexes that give substantial C=C bond cleavage products, the oxidation of alkenes by [Ru (0)2(por)] affords epoxides in good yields.Stereoretentive epoxidation of trans- and cw-stilbenes by [Ru (0)2(L)1 (L = TPP and sterically bulky porphyrins) has been observed, whereas the reaction between [Ru (0)2(OEP)] and cix-stilbene gives a mixture of cis- and trani-stilbene oxides. Adamantane and methylcyclohexane are hydroxylated at the tertiary C—H positions. Using [Ru (0)2(i)4-por)], enantioselective epoxidation of alkenes can be achieved with ee up to 77%. In the oxidation of aromatic hydrocarbons such as ethylbenzenes, 2-ethylnaphthalene, indane, and tetrahydronaphthalene by [Ru (0)2(Z>4-por )], enantioselective hydroxylation of benzylic C—H bonds occurs resulting in enantioenriched alcohols with ee up to 76%. ... 

Iron porphyrin dimers, iron(III) /a-oxodimcr iron(III) porphyrin, for example, are used as biomimetic models of oxidation catalysts [98], It is shown that [Fe(TFPP)]20 and other modifications regioselectively oxidize adamantane and cyclohexane in the presence of iodosylbenzene (PhIO). Comparison of these results with corresponding monomeric analogs indicates the efficiency of the FeP dimer at the level of the monomeric one. 

In the anodic oxidation, adamantane is a unique compound among alkanes. It has a rather low oxidation potential, and its anodic oxidation in acetonitrile affords acetamidoadamantane (1 equation 6) in 90% yield.<... 

Oxidation of C-H bonds. Carbonyl compounds are obtained from alcohols by oxidation with aq.H Oj-MTO. Some hydrocarbons are also oxidized adamantane to 1-adamantanol (88%), cii-decalin to ciy-4a-decalol (90%), and trany-decalin to trany-4a-decalol (20%). 

Matrix isolation / vapor deposition reaction of Al with ethylene oxide / adamantane matrix complex formation... 

Although it is not a reaction of alkenes, oxidation of some alkanes with Pd(ll) is cited here. 1-Adamantyl Irilluoroacetate (155) was obtained in above 50% yield by the reaction of adamantane with Pd(OAc)2 in trifluoroa-cetic acid at 80 C[171]. 

This dry ozonation procedure is a general method for hydrox-ylation of tertiary carbon atoms in saturated compounds (Table 1). The substitution reaction occurs with predominant retention of configuration. Thus cis-decalin gives the cis-l-decalol, whereas cis- and frans-l,4-dimethylcyclohexane afford cis- and trans-1,4-dimethylcyclohexanol, respectively. The amount of epimeric alcohol formed in these ozonation reactions is usually less than 1%. The tertiary alcohols may be further oxidized to diols by repeating the ozonation however, the yields in these reactions are poorer. For instance, 1-adamantanol is oxidized to 1,3-adamantane-diol in 43% yield. Secondary alcohols are converted to the corresponding ketone. This method has been employed for the hydroxylation of tertiary positions in saturated acetates and bromides. 

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

Dimerization and condensation of pentane-2,4-dione by molybdenum(VI) oxide tetrachloride (MoOC14) affords l,3,5,7-tetramethyl-2,4,6,8-tetraoxa-adamantane, the structure of which is determined by elemental analysis, IR, mass, and PMR spectroscopy.188... 

Face selectivity in the 1,3-dipolar cycloaddition reactions of benzonitrile oxide and its p-substituted derivatives with 5-substituted adamantane-2-thiones,... 

The ruthenium-substituted sandwich-type POM WZnRu2(OH)(H20)(A W9034)2]11 (X- Zn2+ or Co2+, Figure 13.1) catalyzed the selective hydroxylation of adamantane with Oz as an oxidant[58,59] ... 

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. 

The one-electron oxidation of iV-benzylphenothiazine by nitric acid occurs in the presence of /i-cyclodextrin, which stabilizes the radical cation by incorporation into its cavity. The reaction is inhibited by adamantane, which preferentially occupies the cavity. Novel Pummerer-type rearrangements of / -sulfinylphenyl derivatives, yielding /7-quinones and protected dihydroquinones, and highly enantioselective Pummerer-type rearrangements of chiral, non-racemic sulfoxides have been reviewed. A comprehensive study has demonstrated that the redox potential for 7- and 8-substituted flavins is linearly correlated with Hammett a values. DFT calculations in [3.3.n]pro-pellanes highlight low ionization potentials that favour SET oxidative cleavage of the strained central C-C bond rather than direct C-H or C-C bond attack. Oxidations and reductions in water have been reviewed. ... 

The phosphorus oxides, imides, their derivatives and their analogs usually have the adamantane-type structure shown in scheme 1. 

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