The Development of Carbocation Theory

These two papers were the origin of the concept that organic carbon cations, which in those days became known as carbonium ions, were far more widespread in organic reactions than previously anticipated. Indeed, these early investigations caused more controversy and more experimental work to unambiguously prove the existence of what are now called carbocations than any other single problem in American chemistry. 

A reaction not too distant (in fact, rather close if you overheat your own ) from the one that is to be carried out below, but one that also included a rearrangement along with the dehydration, was studied by Dorothy Bateman and C. S. Speed Marvel at the University of Illinois as early as 1927. 

Within 2 years of the publication of the Whitmore paper, Robinson proposed the formation of the steroids (including cholesterol) from squalene (a C30 polyunsaturated polyisoprene molecule) via an incredible series of intermediates and rearrangements. Later, following the elucidation of the structure of lanosterol, R. B. Woodward and K. Bloch made a brilliant proposal that at once rationalized the biosynthetic origin of both lanosterol and cholesterol and implicated lanosterol as an intermediate in cholesterol bios)mthesis. Their mechanism involved the concerted (bonds made and broken simultaneously) cydization of four rings, as well as four rearrangements 

The elucidation of fhese biochemical pafhways is further evidence of fhe major impacf fhaf our undersfanding of carbocation chemisfry has had on relafed fields, such as biochemisfry. 

The formation of an aUcene (or alkyne) frequently involves loss of a proton and a leaving group from adjacent carbon atoms. The generalized reaction scheme is shown below. 

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