Die Hydrolyse von 6 exo ‐substituierten 2 exo ‐ und 2 endo ‐Norbornylestern der p ‐Toluolsulfonsäure. Norbornanreihe. 3. Mitteilung

The Hydrolysis of 6 exo ‐Substituted 2 exo ‐ and 2 endo ‐Norbornyl p ‐Toluenesulfonates. Norbornane Series. Part 3 Hydrolysis of the 6 exo ‐substituted 2 exo ‐ and 2 endo ‐norbornyl p ‐toluenesulfonates 1b ‐ 1 and 2b ‐ 1 , respectively, in 70% dioxane led to different amounts of the following products: Unrearranged 2 exo ‐norbornanols 3 and norbornenes 5 , accompanied in somes cases by small amounts of the rearranged R endo ‐epimers 4 and 6 and by norticyclenes 7 . When the 6 exo ‐substituent was a nucleophilic group as in 1e ‐ 1 and 2e ‐ 1 , various amounts of tricyclic products were also formed by endo ‐cyclization. These results show that the 2 exo ‐ and 2 endo ‐esters 1 and 2 , respectively, react by way of different intermediates. In cases where the 6 exo ‐substituent was an n ‐electron donor, as in 1m ‐ r and 2m ‐ r , quantitative fragmentation to (3‐cyclopentenyl)acetaldehyde (13) occurred.