A Historical Position of the Electronic (Electrochemical) Theory of the Course of Organic Reaction by R. Robinson

Abstract

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.