Classical carbonium ions. Part V. Stereochemistry of substitution in the solvolysis of 2-adamantyl and 2-methyl-2-adamantyl derivatives

Abstract

Derivatives of the two 5-methyladamantan-2-ols and of the two 2,5-dimethyladamantan-2-ols have been submitted to solvolysis conditions, and the products have been analysed. The secondary alcohol derivatives show a preference for the formation of products of retained configuration; in the tertiary derivatives a similar but much weaker tendency is observed. Superimposed on these tendencies is one, similar in magnitude, favouring the formation of products of preferential nucleoPhilic attack from the side syn to the 5-methyl group. These preferences are rationalised.