Stereochemistry of acid-catalyzed cleavage of 7-chloro-1-methylnortricyclene in deuterated medium; evidence for edge protonation of nortricyclenes

Cleavage of 7-chloro-1-methylnortricyclene (1e) in D 2 SO 4 –DOAc yields deuterated syn-7-chloro-1-methyl-exo-2-norbornyl acetate (3a-d) (1.04 excess d per molecule) and deuterated anti-7-chloro-1-methy l-exo-2-norbornyl acetate (3b-d) (1.28 excess d per molecule) as the kinetic products. 1 H and 2 H nuclear magnetic resonance spectroscopic analysis of the corresponding alcohols complexed with Eu(fod) 3 shows that deuterium is located endo at …