Adamantane oxidative rearrangement

Adamantane and cis-decalm were hydroxylated with high selectivity, complete stereo-retention, extraordinarily high rates (up to 800 turnovers min ), and high efficiency with up to 15,000 turnovers. Similar conversions were obtained when Ru(VI)(TPFPP)(0)2 and Ru(VI)(TPFPBr8P)(0)2 were used as catalysts. Oxygenation of less reactive substrates such as benzene and cyclohexane proceeded with lower but still significant turnover numbers (100-3,000). Tertiary vs secondary selectivity in adamantane oxidation was above 210. No rearrangement products were detected in cw-decalin hydroxylation. 

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. ... 

Adamantylideneadamantane has been prepared by (1) photolysis of 2-adamantylketene dimer,2 (2) reduction of 4< -chloroadaman-tylideneadamantane with sodium in liquid ammonia,3 (3) rearrangement of spiro[adamantane-2,4 -homoadamantan-5 -ol] with Lewis acids,4,5 (4) reduction of 2,2-dibromoadamantane with magnesium6 or zinc-copper couple,7 and (5) treatment of the azine of 2-ada-mantanone with hydrogen sulfide, followed by oxidation with lead tetraacetate and heating with triphenylphosphine.8... 

Adamantane-2-earboxyUe acU. In a new, convenient synthesis of adamantane-2-carboxylic acid (4), adamantanone (1) is treated with dimethyloxosulfonium methylide to give 2-mcthyIeneadaman(ane epoxide (2). This is rearranged by treatment with boron trifluoride etheratc to the aldehyde (3, unstable). Oxidation with Jones reagent gives (4) in an overall yield of about 70% from (1). 

Spiro(adamantane-2,2 -adamantane) (223) has been synthesized from diketone (224) by selenium dioxide oxidation and ring-contraction by a benzilic acid rearrangement and also from (225), which is obtained by rearrangement of (226). Also noted are C-labelling studies which show that Wolff... 

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