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A new method of obtaining molecular reorientational dynamics from 13C spin-lattice relaxation data of aromatic carbons in viscous solutions is applied to 13C relaxation data of both the cation and anion in the ionic liquid, 1-ethyl-3-methylimidazolium butanesulfonate ([EMIM]BSO3). 13C pseudorotational correlation times are used to calculate corrected maximum NOE factors from a combined isotropic dipolar and nuclear Overhauser effect (NOE) equation. These corrected maximum NOE factors are then used to determine the dipolar relaxation rate part of the total relaxation rate for each aromatic 13C nucleus in the imidazolium ring. Rotational correlation times are compared with viscosity data and indicate several [EMIM]BSO3 phase changes over the temperature range from 278 to 328 K. Modifications of the Stokes-Einstein-Debye (SED) model are used to determine molecular radii for the 1-ethyl-3-methylimidazolium cation. The Hu-Zwanzig correction yields a cationic radius that compares favorably with a DFT gas-phase calculation, B3LYP/(6-311+G(2d,p)). Chemical shift anisotropy values, Deltasigma, are obtained for the ring and immediately adjacent methylene and methyl carbons in the imidazolium cation and for the three carbon atoms nearest to the sulfonate group in the anion.

The ionic liquids 1-ethyl-3-methylimidazolium tetrafluoroborate ([EMIM][BF4]) and 1-methyl-3-propylimidazolium tetrafluoroborate ([PMIM][BF4]) were studied by H,H-NOESY NMR using a cross-relaxation matrix analysis. Cross-peak intensities are seen to increase with increasing mixing time. Experimental and theoretical hydrogen-hydrogen distances are in agreement at short mixing times (50 ms). Mixing times longer than 50 ms result in an increasing contribution of spin diffusion that produces unrealistically short hydrogen-hydrogen distances. Gas-phase ab initio molecular structures are obtained using Hartree-Fock (HF) and density functional theory (B3LYP) methods at the 6311 + G(2d,p) basis set level. The hydrogen-hydrogen distances obtained from the theoretical structures are in reasonable agreement with those calculated from the cross-relaxation matrices.

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Ind. Eng. Chem. Process Des. Dev. 1983, 22, 401-409 40 1 Nomenclature C = conversion factor between partial pressure and concentration, mol/m3, Pa E = eddy diffusivity, m2/s H = height of an increment, m H,, = total bed height, m I = increment index J = gas component index, J = Hz, CO, CO2, CH4, HZS, H20, kl, k4 = constants, l / s k2: k3, k5, k6' = constants, 1/Pa k3 = constant, 1/Pa0.= k6 = constant, 1/Pa0.05 k7 = constant, mol/kg, s, Pa2 k8 = constant, dimensionless K H Kco KCO, K H = constants, 1/Pa P, $Azo, P&, PCO, $H2 = partial pressure, Pa R = production rate, mol/s rc = reaction rate of fixed carbon, mol/kg, s reo, = reaction rate of C02 in ri, i = 1-3 reaction rate of fied conversion rate of C02 in the shift reaction rpi, i = Hz, CO, COZ, CHI, H20, HzS; pyrolysis yield of component i, mol/kg of shale V = volumetric gas flow, m3/s uo = superficial gas velocity, m/s u = gas velocity, m/s y = dispersion parameter, dimensionlesse r a t u r e Cited Berggren, J.C.; Bjerle, I.; Eklund, H.; Karlsson, H.; Svensson, 0. Chem. Eng. Scl. 1980, 35, 448. BJerle, I.; Eklund, H.; Svensson, 0. I d . Eng. Chem. Process Des. Dev. 1980, 19, 345. Bjerle, I.; Eklund, H.; Llnn6, M.; Svensson. 0. I d . Eng. Chem. Process Des. Dev. 1982, 21, 141. Eklund, H.; Llnder, 0.; Svensson, 0. "A Klnetlc Study of the Heterogeneous Shlfi Reactlon over Shale Char and Kerogen Free Ash"; Report, Lund Instltute of Technology, Dept of Chemical Engineering, 1980. Qeldart, D. Powder Techno/. 1973, 7, 285. Kato, K.; Wen, C. Y. Chem. Eng. Scl. 1969, 24, 1351. Park, D.; Levensplel. 0.: FitzgeraM, T. J. Fuel 1981, 60, 295. 0 2Mixtures of two-, three-, and four-ring (naphthalene, phenanthrene, and pyrene) structures were hydrocracked over a nickel-tungsten sulfide uttrastable zeolite Y catalyst. The hydrocracking of tetralin and phenanthrene proceeds by elimination of butanes to form CB and Clo hydrocarbons primarily. Isomerization of saturated six-member rings to methyl-substituted five-member rings is also prominent. The presence of 1-cyclohexyl-2-phenylethane in the products from phenanthrene hydrocracking suggests an akematlve reaction path for the hydrocracking of structures containing adjacent saturated rings. Pyrene hydrocracking proceeds primarily by elimination of propane followed by butanes ellmination, Le., CIB -, C,, -Clo -Ce. The C13 intermediates are mostly h drogenated phenalenes.The zeolite-based catalyst was very active in hydrocracking pyrene (critical diameter = 9 Ay ) and smaller molecules.The perhydropyrene component of the feed mixture was relatively inert, but it could not be established whether this was due to a molecular sieve effect or intrinsic chemical kinetics factors.

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For study of the chemistry of an amino acid derived hydrodisulfide (10, Me2C(SR)CH(NHAc)C02Me, R = SH), a synthetic route to a hydrodisulfide derivative of TV-acetyl-DL-penicillamine was developed. Conversion of IV-acetyl-DL-penicillamine (3) to the ester (4, R = H) was accomplished with diazomethane. With acetylsulfenyl chloride, 4 gave the acetyl sulfide (5, R = Ac) instead of the disulfide (7, R = SAc). With (methoxycarbonyl)sulfenyl chloride, 4 gave the corresponding unsymmetrical disulfide (8, R = SC02Me), which could not be converted to the hydrodisulfide. Conversion of 4 to the sulfenyl iodide (9, R = I) and treatment with thioacetic acid regenerated 4. With acetyl methoxycarbonyl disulfide, however, 4 gave the acetyl disulfide 7. Methanolysis of 7 then gave the hydrodisulfide 10. Solutions of 10 in chloroform were unchanged after 6 days at room temperature and 1 day at 55 °C and then consumed the expected amount of iodine. Washing with bicarbonate led to immediate decomposition; neat 10 completely decomposed during storage at -10 °C for 36 h, and the half-life of 10 in HCl-methanol was about 12 h. Treatment of 10 with cyanide ion gave thiocyanate ion, and treatment with 2,4-dinitrochlorobenzene gave a dinitrophenyl derivative [13, R = 2,4-(N02)2C6H3S] identical with 13 prepared from 4 by using 2,4-dinitrobenzenesulfenyl chloride.