The electron in organic chemistry. III. The thermal and hydrolytic stability and instability of the carbon-to-carbon bond

Abstract

The authors discuss briefly the functions and criteria of merit of scientific models in general. In the light of this prefatory statement the graphic aids to exposition employed by the writers are described as constituting a simple and co?ivenient system of notation for indicating energy relationships. The mechanism, validity, and limitations of the method adopted for the determination of relative electronegativities of organic radicals are discussed. The breadth of applicability of the authors' system of notation is noted, but certain natural limitations are pointed out. The method of applying the system to the + + + THE SCIENTIFIC MODEL, ITS FUNCTIONS AND CRITERIA OF MERIT IT SEEMS to the writers desirable, even at the expense of some repetition, to preface the third article of this series with a few further remarks on scientific models, their functions and criteria of merit. Briefly, the model is a tool whereby we hope to attain one of the primary ends of science-generalization. By its use we hope to correlate apparently isolated phenomena, to classify and order facts in such a manner that they take on a discernible pattern. Secondary and perhaps more utilitarian potentialities of the model lie in its mnemonic and predictive aspects. It is easier to remember associated than isolated facts; also it is often possible to deduce forgotten qr totally unknown facts from remembered generalizations.The criteria of merit in a model are, therefore, as Langmuir (2) has stated them-generality and convenience, the latter of which implies also simplicity. Superficially it might appear that generality and simplicity are fundamentally incompatible-that, as a model is adapted to cover an ever-widening range of subject matter, it must necessarily become more complicated in the process. In refutation of this idea, however, let us consider the snowflake. Its crystallography is hexagonal. To specify a particular snowflake it is necessary to add numerous details not obviously inferable from our original statement, but the most * Parts I and II of this series (Kh. and R.

Henry Gilman: American Pioneer in the Rise of Organometallic Chemistry in Modern Science and Technology

“…The similar importance of ligands in organometallic reactivity was also demonstrated by Morris Kharasch in his studies on the competitive cleavage reactions of organomercurials by HCl (Scheme ) . The reactivity of the cleaved R−Hg bond was found to decrease as R = o - and p -methoxyphenyl, o - and p -tolyl, phenyl, o - and p -chlorophenyl, various alkyls, benzyl, 2-phenylethyl.…”

The Action of Grignard Reagents on 2-Methoxy-1-Naphthonitrile

“…negativity of the alkyl and aryl groups. A similar parallel has been noted (16) with respect to the hydrolytic stability of carboxylic acids.…”

Metallic Salts of Alcohols and Alcohol Analogs.

“…Their results, supplemented by additional information on benzene (124, 430), are abbreviated in table 1, each acid being able to displace those below it more or less completely. It is questionable whether the relative affinities of organic radicals for the electron pair (207), which Ethane determine the acidities of their hydrogen compounds, have actually been measured by the relative rates of competitive reactions (6).…”