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Amidation of amino acids using dichloro(methyl)(3,3,3-trifluoropropyl)silane (MTFPSCl2) and imidazole is described. MTFPSCl2 activates the carboxy group and protects the α-amino group of amino acids. The amidation proceeded with 19 amino acids and 19 amines, including α-branched amines and anilines; the corresponding amino acid amides were synthesized in good-to-high yields (up to 96%) with low-to-no racemization.

As the mileage of electric railways increases and deterioration over time progresses, the contact wire is more likely to wear, and the contact wire and the contact strip may separate. At that time, the contact wire is damaged and broken by arc generation and fusion and evaporation repetition. It is necessary to figure out the damage mechanism for stable supply of electricity and long-life and low cost of facility. However, it is difficult to clarify this phenomenon with experiment because it is a complicated physical phenomenon. Therefore, the elucidation of physical phenomenon using numerical analysis is required. The arc behavior and temperature distribution have been elucidated by the numeral method 1 - 5 . In this research, the simulation method considering electrode descent was developed in order to analyze the arc close to the actual phenomenon. As a result, the arc followed the descent of the contact strip and spread because of thermal diffusion as the distance between the electrodes increased. Therefore, the arc temperature distribution plays an important role to elucidate the disconnection of contact wire.