www.asiachem.news December 2021 | 109 and monovalent alcohols to give experimental proofs to the polar molecular theory of organic substances postulated by Dutch physicist Peter Debye (1884-1966).44 With his student-day research recognized, Mizushima was appointed assistant professor at Tokyo’s Department of Chemistry in 1927 and then traveled to Europe to work at the University of Leipzig with Debye himself in 1929-31. While in Germany he learned quantummechanics firsthand from Debye and became one of the first Japanese chemists who introduced quantum mechanics to Japan in the 1930s.45 Upon returning to Tokyo Imperial University, Mizushima started with his student, Morino Yonezō 森野米三 (1908-95), a path-breaking research in conformational analysis, coining around 1940 the “gauche” form for a conformation where two vicinal groups are separated by a 60-degree torsion angle. This research was made possible by Mizushima’s additional post from 1934 as chief researcher at RIKEN and his promotion to full professorship in 1938 as the successor of Katayama. His “gauche” research garnered him an international reputation and brought him a scholarly network with first-class colleagues in physical chemistry such as the two-time Nobel laureate Linus Pauling (1901-1994). Mizushima’s work as a bureau member of the IUPAC in 195567 would not have been possible without his growing reputation and international network. One of Mizushima’s students, Nagakura Saburō 長倉三郎 (1920-2020) developed the intermolecular charge-transfer theory of chemical reactions postulated by his American teacher, Robert S. Mulliken (1896-1986), starting with the publication of two papers in the Journal of Chemical Physics and the Journal of the American Chemical Society in 1955. Nagakura became a leading figure in postwar Japanese physical chemistry together with Akamatsu, Inokuchi, Morino, and Fukui Kenichi (cf. the section on the Kyoto school and the first Japanese Nobel Laureate in Chemistry below).46 Ogawa Masataka was first trained as an inorganic chemist and honed his analytical skills with Divers at Tokyo.47 Ogawa then studied overseas in 1904-1906 with William Ramsay (1852-1916) at UCL and encountered his life-long research project on a new element by means of analyzing the newfound mineral, thorianite. After getting back to Japan, he continued the same project with another mineral, molybdenite, and announced the discovery of element 43, naming “Nipponium” (Np) in 1908 after the name of his country, Nippon 日本. Ogawa was appointed professor at the Tohoku Imperial University in 1911, and his assistants and students there worked on the Nipponium project, though without success in reproducing Ogawa’s result. The discovery of element 43, later named technetium (Tc), in 1937 meant that Ogawa’s research was in the wrong. Recent reassessments of Ogawa’s work by chemist historian Yoshihara Kenji, however, claimed that Ogawa did discover a new element but that it was not the 43rd element as he had claimed but the 75th element, today’s rhenium (Rh). He is now considered in Japan as a great pioneer in searching new elements in his country, especially in the wake of the successful synthesis of the transuranium element of atomic number 113 in 2004 by RIKEN researchers. Their proposed name, nihonium (Nh) (after another reading of the country name, Nihon 日本), was approved by the IUPAC in November 2016. Figure 7: Ogawa Masataka. Courtesy of the Tohoku University Archives. Majima Rikō (born Toshiyuki but generally referred to as “Rikō” by himself and his colleagues) majored in organic chemistry at Tokyo and worked with Sakurai, who was originally trained as organic chemist by Williamson.48 Majima however received little advice from Sakurai and taught largely himself the craft of organic chemical research. He started his first structural research of urushiol, the main component of raw lacquer juice, based on his research strategy to compete with Western chemists by studying Japanese local products with analytical techniques of Western chemistry, taking advantage of the proximity to the localities of these products. During his overseas study in 1907-1911, Majima worked with Carl Harries (1866-1923) at the University of Kiel and Richard Willstätter (1872-1942) at the Zurich Polytechnic to learn the cutting-edge techniques of organic chemistry such as vacuum distillation, ozonolysis, and catalytic reduction that could be applied to his urushiol project. He was appointed professor (as Ogawa) at Tohoku Imperial University in 1911, completed the urushiol project and established influential research schools in organic and natural product chemistry first at Tohoku and later at RIKEN and other universities such as Osaka Imperial University (est. 1931). In so doing, Majima paid great attention to equipping laboratories with adequate facilities to support experiments with the technique he brought back from Europe. For example, he carefully designed water supply facilities on the Tohoku Imperial University campus in Sendai, where there was no running water yet, to provide enough water pressure to be used for vacuum (reduced pressure) distillation.49 Figure 8: Majima Rikō. Courtesy of the Tohoku University Archives Nozoe Tetsuo 野副鐵男 (1902-96), arguably the most important student of Majima, was graduated in 1926 from the Department of Chemistry at Tohoku Imperial University with Majima as his thesis advisor.50,51 Nozoe moved to the then Japanese colony of Formosa (Taiwan) to take up a research appointment at the Laboratory attached to the Government of the Governor-general of Taiwan in Taipei (“Taihoku” in Japanese) in 1926. He was appointed assistant professor at the newly founded Taihoku Imperial University in 1929 and promoted to a full professorship in 1937. Following in the footstep of his mentor, Nozoe started his research on the structure of hinokitiol, the oil extracted from Chamaecyparis taiwanensis, a species of cypress native to Taiwanese mountains in 1935. He confirmed by 1940 that hinokitiol has a seven-member ring structure and yet exhibits aromaticity. After the end of World War II and Taiwan’s retrocession to Chinese sovereignty, Nozoe stayed in Taipei until 1948 as the chemistry professor at the National Taiwan University (reorganized from Taihoku Imperial University in 1945). Appointed a chemistry professor of his alma mater, the Department of Chemistry at Tohoku University, in 1948, Nozoe’s hinokitiol research gradually became internationally known and made him one of the pioneers of
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