Studies in superacidic chemistry

Chapter 1 gives a brief introduction emphasizing the goals of my research. It also presents an overview of acids and their acidity while demonstrating the significant role that superacidic chemistry had played in allowing the development of both new and useful applications.; Chapter 2 describes the development of a novel chemical purification procedure for C{dollar}sb{lcub}60{rcub}{dollar} from fullerene extract using the differential complexation of C{dollar}sb{lcub}60{rcub},{dollar} C{dollar}sb{lcub}70{rcub}{dollar} and higher fullerenes with aluminum trichloride (or its conjugate acid) in CS{dollar}sb2{dollar} solution.; In chapter 3 the application of 1-(chloromethyl)-4-fluoro-1,4-diazabicyclo (2.2.2) octane bis(tetrafluoroborate) (Selectfluc{dollar}rmsp{lcub}TM{rcub}{dollar} F-TEDA-BF{dollar}sb4{dollar}(TEDA = triethylenediamine)) in the presence of trifluoromethanesulfonic acid as a very effective reagent for the direct electrophilic fluorination of a wide variety of aromatic compounds under mild reaction conditions with excellent yields is described.; In chapter 4 the discovery of Nafion-H as a highly efficient solid acid catalyst for the bimolecular conversion of alcohols to ethers in excellent yields is discussed.; Chapter 5 describes the catalysis of adamantylation of substituted benzenes with 1-bromoadamantane by solid acids including, acidic ion exchange and ionomer resins, HY zeolite, sulfated zirconia and supported superacids on HY zeolite and SiO{dollar}sb2.{dollar} Adamantylations were carried out in excellent yield giving predominantly para products without formation of byproducts. High regioselectivity of Amberlyst was observed with almost exclusive formation of p-adamantylated-benzenes. AM1, PM3 and MNDO semiempirical calculations of heats of formation were also investigated. The temperature dependence of adamantylation was also investigated allowing the optimization of p-substituted product in excellent yield and selectivity.; Chapter 6 describes the preparation and investigation of several substituted benzylic mono- and dications by {dollar}sp1{dollar}H and {dollar}sp{lcub}13{rcub}{dollar}C NMR spectroscopy and DFT/IGLO calculations. Comparison with calculated structure of benzene dication (6) is discussed. Attempts to generate 2,3,5,6-tetramethyl-1,4-dimethyldiyl dication (8), as well as, attempts to generate the mesityl-2,4,6-trimethyltriyl trication (10) are also discussed. Attempts to determine the crystal structures of some benzyl monocations are described.