p-Xylene was synthesized by [4 + 2] cycloaddition of biomass-derived ethylene and dimethylfuran over Lewis acid zeolite catalyst, Zr-BEA, with 90% selectivity in products.

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The (e, e 0 p) reaction was studied on targets of C, Fe, and Au at momentum transfers squared Q 2 of 0.6, 1.3, 1.8, and 3.3 GeV 2 in a region of kinematics dominated by quasifree electron-proton scattering. Missing energy and missing momentum distributions are reasonably well described by plane wave impulse approximation calculations with Q 2 and A dependent corrections that measure the attenuation of the final state protons. [S0031-9007 (98) The (e, e 0 p) reaction with nearly free electron-proton kinematics (quasifree) has proven to be a valuable tool to study the propagation of nucleons in the nuclear medium [1][2][3]. The relatively weak interaction of the electron with the nucleus allows the electrons to penetrate the nuclear interior and knock out protons. These studies complement nucleon-induced measurements of proton propagation in nuclei which give more emphasis to the nuclear surface. This paper reports the first results of a systematic study of the quasifree knockout of protons of 300-1800 MeV kinetic energy from carbon, iron, and gold targets. This energy range includes the minimum of the nucleon-nucleon (N-N) total cross section, the rapid rise in this cross section with energy above the pion production threshold, and extends to the long plateau in the energy dependence of the N-N total cross section. These features of the N-N interaction would be expected to be reflected in the energy dependence of attenuation of protons as they pass 5072 0031-9007͞98͞80(23)͞5072(5)$15.00

Routes to benzoic acid starting from high-yield, hemicellulose-derived furfural derivative, furan, manufactured from biomass are reported. These routes involve Diels-Alder and dehydration reactions of furan and acrylic acid (or methyl acrylate) in a two-step reaction protocol that minimizes polymerization side reactions associated with furan and acrylic acid. The Diels-Alder reaction of furan and methyl acrylate (or acrylic acid) was run at 298 K catalyzed by Lewis acidic (Hf-, Zr-and Sn-Beta) zeolite catalysts and relatively high turnover frequency (~2 h -1 ) and no side reactions were observed. The dehydration of the oxanorbornene was performed homogeneously at low temperatures (298 to 353 K) in mixtures of methanesulfonic acid and acetic anhydride in 96 % yield. This is compared to only a 1.7 % yield of methyl benzoate obtained for the dehydration of the oxanorbornene in neat methanesulfonic acid. The effect of oxanorbornene concentration and stereochemistry were found not to significantly decrease yield to aromatics while dehydration of the carboxylic acid form of the oxanorbornene led to a drop in selectivity to 43 % at complete conversion in mixtures of methanesulfonic acid and acetic anhydride. This reaction sequence could be an important entry point for selectively directing high-yield, hemicellulose-derived furans to aromatic products used in the existing chemical process industry.