There is provided a preparation process in which a N\u2014H group of a heteroaromatic ring compound having a N\u2014H group in its ring is converted directly to a N\u2014Rf group at a high reaction efficiency without using a catalyst. The bar has an angled mating surface that engages a recessed surface formed in a slot of the bond beam. The plurality of LEDs are arranged in a plurality of rows in the thickness direction of the same side surface of the light guide plate so as to extend in a longitudinal direction of the light incidence surface. A representation of at least a portion of the anatomical structure can be graphically generated based on the geometric shapes, e. The method also includes applying the measuring tape to the circumferential surface of the holder while maintaining the tensioning force. More particularly the invention concerns the preparation of 4-chloro-4-thiomethyldiphenylether.