2-Adamantanone synthesis

The reported 2731 yield of adamantanone oxime from this reaction (63 %) is misleading since it is based on Cl2 as the limiting reagent. Careful product analyses have shown that the overall ratio of tertiary to secondary substitution products ( 2) is quite normal275), While this reaction is clearly much less useful for the preparation of methylene substituted adamantanes than the ionic processes discussed above, it may be applicable in more specialized cases such as, for example, the synthesis of polyalkylsubstituted adamantanones where the ionic processes work poorly. 

The Baeyer-Villiger oxidation has been utilized as an element of several novel functional group manipulations. Suginome and Yamada converted adamantanone (64) to 2-thiaadamantane (66) via the lactone (65 Scheme 19). Eaton et al.P in the synthesis of pentaprismane (70) from homopentaprismanone (67 Scheme 20), required that a leaving groiq) be introduced a to the carbonyl group in or r to carry out a Favorskii ring contraction. Oxidation of (67) afforded lactone (68), which was converted in several steps to the requisite hydroxy ketone (69). 

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). 

Glycidic esters. Wynberg et all state that the simplest synthesis of adaman-tane-2-carboxylic acid (4) involves conversion of adamantanone (1) into the glycidic ester (2), pyrolysis to adamantane-2-carboxaldehyde (3), and finally chromic acid oxidation. The overall yield is 71 %. 

Peterson aikenation of carbonyl compounds with trimethylsilylmethoxymethyl carbanion (14) can also give enol ethers. An example is the reaction of (14) with adamantanone. Another method of alkene synthesis is the elimination of CO2 and H2O from a P-hydroxycarboxylic acid. If the carboxylic acid is substituted by an a-alkoxy group, the reaction can be used for the synthesis of enol ethers, as illustrated in Scheme 4. ... 

Synthesis of mesoporous molecular sieves MCM-41 and MCM-48 was carried out under microwave and hydrothermal conditions. Molecular sieves prepared were characterized using X-ray powder diffraction, scanning electron microscopy, nitrogen adsorption isotherms and infrared spectroscopy to evaluate the properties of these materials. It was observed that mesoporous molecular sieves synthesized under microwave conditions exhibit higher activity in oxidation of adamantanone by hydrogen peroxide to the respective lactone (Baeyer-Villiger oxidation). 

In this contribution we report on the incorporation of tin into the mesoporous molecular sieves MCM-41 and MCM-48 comparing traditional hydrothermal approach with microwave synthesis of these materials. X-ray powder diffraction, nitrogen adsorption isotherms, scanning electron microscopy and FUR of probe molecules were employed to characterize these molecular sieves. Oxidation of adamantanone with hydrogen peroxide was used as model reaction. 

Syntheses of the formamidine AdNHCH=NAd from 1-aminoadamantane hydrochloride (AdNH2,HCl) by reaction with s-triazene in pyridine and of the amide from p-(2-furyl)acrylie acid chloride and AdNH2 have been recorded the amide has antiviral activityReaction of 3-methylpentadienyl anion with adamantanone affords (668 75%) as the exclusive product the anion is a convenient reagent for the introduction of a 1,3-diene unit of the above type, and applications to terpene synthesis are discussed." Thermolyses of esters of P-hydroxyalkyltrimethylsilanes,... 

However, little success was met in the one-step synthesis of l-(2-adamantyl)-2-methyl-2-phenyl-l-ethanol from 2-chloro-2-phenylpropane, adamantanone and lithium in tetrahydrofuran [36]. But when this reaction was run in the presence of a catalytic amount (1-3 mol%) of the aromatic electron-transfer agent 4,4 -di-tm-butylbiphenyl (DBB), the desired tertiary alcohol was obtained in 67% yield ... 

In this last sentence the authors referred to reports [52, 53] on a one-step synthesis including 1-bromoadamantane and adamantanone ... 

Hyperflorin, an antibiotic isolated from St. John s wort Hypericum perforatum L.), has been found on the basis of chemical and spectroscopic evidence to possess structure (639). ° A review on the conformational analysis of bicyclo[3,3,l]nonanes has appeared,and the conformations of l,5-disubstituted-3,7-dimethyIenebicyclo-[3,3,l]nonane derivatives have been shown, on the basis of lanthanide-induced n.m.r. shifts, to be predominantly in the double-chair form. In a notable paper that contains a wealth of information pertinent to adamantane synthesis, it has been reported that bicyclo[3,3,l]nonane-3,7-dicarboxylic acid, its dimethyl ester, and various derivatives exist mainly in the chair-boat conformation. The synthetic entry to these systems is illustrated for the above diester (643) in which the starting point is adamantanone (640) thus, ring expansion with diazomethane followed by SeOj oxidation gave the a-diketone (641) which was cleaved with periodate to give the diacid (642). Esterification using diazomethane gave (643) which exists, as does the diacid, as... 

Photosensitized addition of singlet oxygen to adamantylideneadamantane gives the peroxide (203). The more usual reaction of formation of a hydroperoxide by the ene reaction is not possible because of the absence of allylic hydrogens in the olefin. Typically the peroxide is thermally unstable and gives adamantanone with chemiluminescent emission. Synthesis and pyrolysis of 1,3-diadamantylallene (204) are described. 

Murray, Jr., R.K. and Babiak, K.A., Synthesis of 8,9-dehydro-2-adamantanone by the oxa-di-7t-methane photorearrangement of 2-protoadamantenone, Tetrahedron Lett., 319, 1974. Mlinaric-Majerski, K., Pavlovic, D., and Sindler-Kulyk, M., Synthesis and photochemistry of 4-methylene-2-protoadamantanone,/. Org. Chem., 58, 252, 1993. 

Suginome, H. and Yamada, S., The replacement of the carbonyl group of adamantanone by an oxygen or sulfur atom and the one-step transformation of 2-methyladamantan-2-ol into 2-oxaad-amantane An efficient new synthesis of 2-oxa- and 2-thiaadamantane, Synthesis, 741,1996. 

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