著者

徳元 琴代

出版者

日本科学史学会

雑誌

科学史研究 (ISSN:21887535)

巻号頁・発行日

vol.28, no.171, pp.161-172, 1989 (Released:2021-09-01)

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In the 1920's, R. Robinson and C.K. Ingold controverted on principles of an electronic theory of organic reactions. They had been investigated how to theorize reactivity of many complicated organic reactions from different points of view―polar (Robinson, alternative polarity) and non polar (Ingold,free affinity). Gradually they were conscious of necessity of new concepts (electron valence) for showing quantitative reactivity in this controversy on nitration reactions of nitrosobenzene and benzilamine etc. from 1924 to 1926. The year,1926, was the turningpoint that they indicated new concepts of reactivity of organic reactions―the density of electron around atoms (Robinson) and the electronic strain around atoms(Ingold). So, they could publish the electronic theory of organic reactions in 1930's. Consequently not only Robinson but also Ingold in this controversy played an important part for forming basic concepts and methods to quantiy their reactivities in the electronic theory of organic reactions.

著者

徳元 琴代

出版者

日本科学史学会

雑誌

科学史研究 (ISSN:21887535)

巻号頁・発行日

vol.26, no.162, pp.65-75, 1987 (Released:2021-09-21)

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R. Robinson published "the electronic (electrochemical) theory of the course of organic reactions" in 1932 and became a pioneer in this field. In general, it was said by science historians,e.g.G.V.Bykov, that Robinson applied the electron shift theory of G N しewis (1916) to organic reactions. But a historical study of Robinson's theory showed me original steps for forming his own theory. Robinson studied organic chemistry under W.H.Perkin,Jr. and synthesized many alkaloids of medicine and dye. In 1910 Robinson synthesized anhydrocotarnine phthalide from cotarnine and phthalide and examined their reaction mechanism. Investigation of the reaction mechenism led to the foundation of his electronic theory He tried to explain the cause of organic reactions not by chemical affinity but by electronic behavior of atoms and atomic groups of molecule So, he considered "reaction center" of molecules and "loose combination" of all molecules in the course of organic reactions. This "loose combination" was expressed with a dotted line called "partial valency" in 1916 Next year, Robinson elucidated that his "partial valency" was different from J.Thiele's one and it appeared by division of normal valency. In 1920,he cleared that partial valency was attributed to activation of one or more molecule taking part in the reactions. In 1922, this activation was distinguished into primary conjugation (on reaction) and secondary conjugation (on structure), and in 1925 the former was called "electromeric effect" and the latter "induced effect". At the same time, Robinson explained that his theory could be translated by "electron" of Thomson-Lewis-Langmuir theory but was different from their theory In short his "electron shift" included the activation in reactions. Activation in reactions was influenced by reagents,too. In 1925, all organic reactions were divided into about 10 types of conjugation which afforded active phase in reactions. His electronic theory was summarized in 1932 and opened a new way of electronical theorization of organic reactions. Thus, studies on the reaction mechanism of the alkaloids syntheses were indispensable for the establishment of Robinson's theory.