Abstract
Comparison of the products of acid-catalysed rearrangements of the pinan-2-ols in aqueous dioxan and acetic acid has shown that in the latter solvent the water molecule generated in the alcohol heterolysis reaction has a strong influence on the products of rearrangement. The acid involved in the reaction is also important, perchloric acid being able to displace the water molecule and give rise to products typical of an intimate ion pair.