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The ortho position of the aromatic ring in 2-aryloxazolines and 2-arylimidazolines is selectively arylated and alkenylated with organic halides in the presence of a ruthenium(II)-phosphine complex. In the case of unsubstituted and para-substituted phenyloxazolines, 1:2 coupled products were obtained preferentially, while 1:1 coupled products were obtained in the case of meta-substituted phenyloxazolines and N-acylarylimidazolines. The reaction is proposed to proceed via the generation of an organoruthenium intermediate, formed by oxidative addition of the organic halide, and ortho-ruthenation directed by the coordination of the 2-oxazolinyl or 2-imidazolinyl group to the ruthenium center.

Isotherms and IR spectra were measured for CO2-MZSM-5 (M = Li +, Na +, K +, Rb +, Cs +) adsorption systems. The observed adsorption characteristics were well approximated by a physical adsorption where the van der Waals force and an electrostatic interaction force are operating: the degree of irreversible adsorption (chemisorption) was less than 10% of the total adsorption. Although the adsorbed CO2 molecule interacts with both the cation and the pore wall, only the CO2-cation interaction can convert the IR inactive u1 vibration into an IR active state. The adsorption model proposed enables us to calculate the initial heat of adsorption as well as the molecular orientation angle of CO2 against the cation site.

Infrared spectra of methane adsorbed by five kinds of ion-exchanged zeolites have been measured, and the results have been compared with adsorption characteristics obtained from the adsorption isotherms measured separately. The shifts of the IR u1 peak position (Aul), the IR absorption coefficient (A), and also the isosteric heat of adsorption (q,?) have been found to be intimately related to the ionic radius of the cation exchanged. Furthermore, the electric field ( E ) of the cationic site has been found to decrease according to the sequence Li+ > Na+ > K+ > Rb+ > Cs+. From these results, it has been postulated that the interaction between the cationic site and a methane molecule plays a dominarit role in the adsorption. In addition, the IR and adsorption data have revealed that there are two kinds of adsorption sites over the zeolite surface, i.e., the silicalite-like site (site 1) and the cationic site (site 2). The difference between the adsorption energy for site 1 and for site 2 has been estimated to be qs2 -20.92 kJ/mol, which has been almost identical with the chemical potential difference evaluated from IR data.