Werner

German-born Swiss chemist. He studied chemistry at the ETH Zurich in Switzerland, graduating in 1889 and working as an unpaid assistant while working under AR Hantzsch, earning his doctorate in 1890. In the winter of 1891, he spent time under PEM Berthelot in Paris, and in 1892 became a private lecturer at the ETH Zurich, and in 1893 became a professor at the University of Zurich. At the time, when the theory of atomic valence proposed by FA Kekulé, who had been successful in organic chemistry, was applied to inorganic compounds, it was difficult to explain cases in which the atomic valence of elements was constant. Werner proposed that the valence of metals be divided into primary and secondary valences, and that the former contributes to bonding with ions, while the latter also contributes to bonding with various neutral molecules, and that the sum of the two is the coordination number specific to the compound. Based on this theory, he experimentally confirmed the number of isomers predicted from the three-dimensional structure of the complex by measuring conductivity, and further succeeded in synthesizing stereoisomers. In 1911, he succeeded in separating optical isomers, proving the coordination theory. This result caused controversy as the thinking at the time attributed optical activity to carbon atoms, but in 1914 he synthesized an optically active complex containing no carbon at all, and demonstrated that optical activity is due to stereochemistry. These results became the foundation of modern inorganic chemistry and had a major impact on other fields of chemistry. For these achievements, he became the first Swiss person to be awarded the Nobel Prize in Chemistry in 1913.

Source: Morikita Publishing "Chemical Dictionary (2nd Edition)" Information about the Chemical Dictionary 2nd Edition

ドイツ生まれのスイスの化学者．スイスのチューリヒ工科大学で化学を学び，1889年卒業後，無給助手を務めながらA.R. Hantzsch(ハンチ)のもとで研究し，1890年学位を取得．1891年冬，パリのP.E.M. Berthelot(ベルトロ)のもとで過ごした後，1892年チューリヒ工科大学の私講師となり，1893年チューリヒ大学の教授となる．当時，有機化学で成功をおさめたF.A. Kekulé(ケクレ)の原子価の理論を無機化合物に適用したとき，元素の原子価を一定としては説明が難しい場合が生じていた．Wernerは金属の原子価を主原子価と副原子価に区別し，前者はイオンとの結合に寄与するのに対して，後者は各種の中性分子との結合にも寄与し，両者の合計は化合物に固有の配位数となると提案した．この理論にもとづいて，錯体の立体構造から予測された異性体の数を伝導度測定から実験的に確認し，さらに立体異性体の合成に成功した．1911年光学異性体の分割に成功し，配位説を実証した．この結果は，光学活性を炭素原子に帰していた当時の考えから論争をよんだが，かれは1914年に炭素をまったく含まない光学活性錯体を合成し，光学活性が立体化学に起因することを示した．これらの成果は現代の無機化学の基礎となり，化学の他分野にも多大な影響を与えた．以上の業績により，1913年スイス人としてははじめてノーベル化学賞を受賞した．

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