SOLVOLYSIS DECOMPOSITION OF 1-ADAMANTYL CHLOROFORMATE - EVIDENCE FOR ION-PAIR RETURN IN 1-ADAMANTYL CHLORIDE SOLVOLYSIS

In hydroxylic solvents, 1-adamantyl chloroformate reacts with loss of carbon dioxide and formation of both solvolysis and decomposition products. The rates of both processes are appreciably sensitive to solvent ionizing power, with the solvolysis slightly more so. The influence of anionic additives is discussed. For mixtures of hydroxylic solvents, the selectivities for the formation of solvolysis products are very similar to those observed in conventional solvolyses of 1-adamantyl derivatives. It is suggested that 1-Ad+Cl” ion pair intermediates are formed, and the observation of collapse requires that an identical collapse, corresponding to internal return, also occurs in 1-adamantyl chloride solvolysis. A comparison with solvolyses of other 1-AdOCOX compounds suggests that the initial ionization is not to l-Ad+(OCOCl) and that the 1-Ad+CT ion pair is formed either in a concerted process or via a very unstable (l-AdOCO)+CT ion pair. © 1990, American Chemical Society. All rights reserved.