A facile method for synthesizing trans-disubstituted cyclopropanes is described. γ,γ-Dimethyl homoallyl alcohols, upon conversion to the corresponding triflate, undergo smooth cyclization to give cyclopropanes in a stereoselective manner (trans) and in a stereospecific manner (inversion of configuration at the chiral center). Various functionalities could be introduced at the α-position of the newly formed cyclopropane ring by treating the cyclization mixture with hetero as well as carbon nucleophiles. Alternatively, treatment of the reaction mixture with triethylamine effects the clean elimination of a triflic acid to give high yields of the cyclopropanes with a 2-propenyl group, which are convertible to the corresponding cyclopropyl methyl ketones by ozonolysis in high yields. Also described is an application of the method to a short-step synthesis of a cyclopropane-containing eicosanoid, related to marine prostanoid biosynthesis.

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The characteristics of a high-pressure pulsed singlet oxygen generator is investigated. This generator was designed for the energy source of new pulsed chemical lasers. A ceramic porous pipe is devised in it to attain the high-pressure pulsed operation. New methods were developed to measure a water vapor pressure and a reaction efficiency in the pulsed singlet oxygen generator system. The maximum singlet oxygen pressure obtained was 35 Torr, and the estimated initial excitation efficiency was 70%–80%

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