Allylcarbinyl tosylate

In 1951 Roberts observed that most cationic reactions of cyclopropylcarbinyl and of cyclobutyl derivatives give the same products in nearly the same ratio.73 For example, cyclopropylcarbinyl and cyclobutyl amines on deamination form the products shown in Equation 6.31.74 Moreover, when allylcarbinyl tosylate (63)... 

Thermolysis of 4-tosyloxybutyl trimethyltin stops at the stage of but-3-enyl-trimethyltin if base (2,6-lutidine) is present, but in the absence of the latter a mixture of methylcyclopropanes, but-l-ene, and other decomposition products is obtained. Posner and Ting have demonstrated that in the alkylation of allylcarbinyl tosylates with organocuprates, reaction does not always take place by oxidative addition-elimination at the copper, and in certain instances the double bond of the ethylenic tosylate can take part in the substitution, with resultant formation of the cyclopropylalkane. 

A set of rapidly equilibrating carbenium ions might account for the rearrangements and the label scrambling but this cannot be the correct explanation, for cyclopropylcarbinyl, cyclobutyl, and allylcarbinyl systems all solvolyze much more rapidly than would be expected from model compounds. Thus, for example, the rate of solvolysis of cyclopropylcarbinyl tosylate is 10 times that of the solvent-assisted solvolysis of isobutyl tosylate.77 Cyclobutyl tosylate solvolyzes 11 times... 

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