We investigated the diastereoselectivity of ring openings for chloro vinyl epoxides with various chlorination reagents. In the chlorinolysis reactions using vinyl epoxides having an allyl alcohol, ...inversion:retention ratios varied depending on the chloride sources. In limited cases, the increase in retention ratio was consistent with the intervention of chloronium ions. In contrast, all vinyl epoxides bearing an α,β-unsaturated ester gave only the inversion products. These results suggest the electron-withdrawing property suppressed the chloronium ions.
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Electron Beam Emission of UT Gyrotron MANABE, Ayuto; TAMAGAWA, Toshiyuki; TABATA, Kuniyoshi ...
Space Solar Power Systems,
2021, Volume:
6
Journal Article
Open access
A gyrotron is a vacuum tube which generates millimeter waves from kinetic energy of gyro motion of electrons. In the University of Tokyo, a gyrotron with power of 600 kW, frequency of 94 GHz and ...pulse duration of 100 microseconds has been developed for the purpose of thrust generation experiments of Microwave Rocket. In order to maximize the energy conversion efficiency, the distribution of magnetic field by the super conducting magnet was measured and the gyrotron was installed. The withstand voltage of 40 kV was confirmed before the beam extraction was examined.
