The Many Chemists Who Could Have Proposed the Woodward-Hoffmann Rules But Didn't: The Organic Chemists Who Knew of the Smoking Guns

It is a reasonable question to ask, why, as of 1965 when the five Woodward-Hoffmann communications appeared, did no other organic chemist discover the orbital symmetry rules for pericyclic reactions? The previous two papers in this 27-paper series on the history of the Woodward-Hoffmann rules discussed the physical chemists, chemical physicists, and theoretical chemists who could have solved the pericyclic no-mechanism problem; and the organic chemists in whose laboratory many of the key hints to this problem were found but still did not solve the problem. The stories of 16 other chemists who knew of (at least portions of) the pericyclic no-mechanism problem are presented in this paper. Social, political, and scientific explanations are presented as partial rationalizations as to why none of these individuals - except Woodward with Hoffmann - solved the pericyclic no-mechanism problem.

Woodward-Hoffmann's Stereochemistry of Electrocyclic Reactions: From Day 1 to the JACS Receipt Date (May 5, 1964 to November 30, 1964)

The publication in January 1965 of the first Woodward-Hoffmann paper, The Stereochemistry of Electrocyclic Reactions, ushered into organic chemistry both an explanation of the stereochemistry and "allowedness" or "forbiddenness" of concerted reactions and an impetus for untold numbers of research projects. In the current paper, details of the collaboration between R. B. Woodward and R. Hoffmann, from when they first met to discuss the solution to the "no-mechanism problem" to the date their first paper was received in the offices of the Journal of the American Chemical Society, will be discussed and analyzed. The primary focus will be on the historically relevant extant documents from the early 1960s. These include Hoffmann's laboratory notebooks describing his research, including his extended Hückel calculations used to explain and predict the stereochemistry of electrocyclic reactions. Drafts of the Stereochemistry of Electrocyclic Reactions paper and letters and notes by Woodward, Jerome Berson, and others will further illuminate the development of this first Woodward-Hoffmann paper.