19066-25-2Relevant academic research and scientific papers
The role of enthalpic and entropic factors in the isomerization equilibrium of aryladamantanes
Pimerzin,Sarkisova
, p. 94 - 102 (2007/10/03)
The chemical equilibrium of five positional isomerization reactions of aryladamantanes with different structures was studied in the liquid phase in the presence of AlCl3 in the range 303-423 K. Contributions to the equilibrium constants were analyzed using experimental and calculated data. The contributions were from symmetry, intermolecular interactions, differences in heat capacities of isomers, overall rotation of molecules, free or hindered rotation of groups in molecules, contribution of vibrations, differences in conformational composition, and intramolecular effects of interaction of substituents in molecules involved in the reaction. The significance of these contributions to the equilibrium constants of the transformations in question was shown. The enthalpies and changes in entropy for the reactions in the liquid and gaseous states were determined and discussed. A comparative analysis of the thermodynamic characteristics of positional isomerization of aryladamantanes, methyladamantanes, methyldiamantanes, and phenylcyclohexanes is given.
Boron Tris(triflate) Catalyzed Adamantylation of Benzene and Toluene with 1- and 2-Haloadamantanes and Adamantanoyl Chlorides. Isomerization of Phenyl- and Tolyladamantanes
Olah, George A.,Farooq, Omar,Farnia, S. Morteza F.,Wu, An-hsiang
, p. 1516 - 1522 (2007/10/02)
Boron tris(triflate) catalyzed adamantylation of benzene and toluene was studied with isomeric 1- and 2-haloadamantanes.The alkylations give 1- and 2-phenyl- and isomeric tolyladamantanes in varying ratios.Interconversion of isomeric 2-phenyl(tolyl)adamantanes into the corresponding 1-phenyl(tolyl)adamantanes was observed through intermolecular isomerization involving adamantyl cations and adamantane, which is formed in significant amount in all the reactions.Decarbonylative alkylation of aromatics with adamantanoyl chlorides was also investigated.Adamantanoylated aromatics were formed only in very low amounts, the major product being adamantylated aromatics in accord with extensive decarbonylation of the adamantanoyl cations.The mechanism of the studies adamantylations was further substantiated by studying the boron tris(triflate) catalyzed isomerization of 1- and 2-aryladamantanes under comparable conditions.
Adamantane-2-spiro-3'-diazirine in reactions with protic and aprotic acids
Isaev, S. D.,Zhalnina, G. G.,Murzinova, Z. N.,Lastovenko, S. I.,Yurchenko, A. G.
, p. 126 - 131 (2007/10/02)
During the action of strong protic acids on adamantane-2-spiro-3'-diazirine addition of the proton is accompanied by the elimination of a molecule of nitrogen and the formation of the intermediate 2-adamantyl cation.In the presence of nucleophiles the latter is converted into the corresponding 2-substituted derivatives of adamantane.Lewis acids promote isomerization of the cyclic diazirine to the linear diazo compound, and the main reaction product is adamantanone azine.Trifluoroacetic acid and bromine react by both mechanisms simultaneously. (In the latter case Br+ plays the role of the proton in the first stage.)
