85611-93-4Relevant academic research and scientific papers
Acid-Catalyzed Hydrolysis of Bridged Bi- and Tricyclic Compounds. XXVII. An Application of the Excess Acidity Method to the Norbornyl Cation Problem
Lajunen, Martti,Himottu, Marja
, p. 957 - 962 (2007/10/02)
Hydrolysis rates and products of exo- and endo-2-phenoxynorbornanes have been studied in concentrated aqueous perchloric acid solutions.The activation parameters, solvent deuterium isotope effects, dependences of the reation rates on acid concentration, products of hydrolysis and the high exo/endo rate ratio (2570) are all in agreement with the A-1 mechanism, in which the norbornyl cation is formed in the rate-limiting stage.The excess acidity method was used to determine first the pKa value (-5.56) and the slope parameter (m* = 1.01) for the oxygen protonation of the endo epimer, and then the slope parameters for the rate-limiting stages of the exo and endo hydrolyses (m* = 1.37 and 1.55, respectively).The slope parameters are somewhat exceptional, and may hint at a more delocalized charge in the transition state of the exo hydrolysis.
REACTION OF exo-2-NORBORNYL AND 1-ADAMANTYL p-TOLUENESULFONATES WITH SODIUM PHENOXIDE IN TETRAHYDROFORAN. IONIZATION OF THE SUBSTRATES UNDER "APPARENTLY-SN2" CONDITIONS
Takeuchi, Ken'ichi,Kato,Yukari,Moriyama, Takamasa,Okamoto, Kunio
, p. 935 - 938 (2007/10/02)
exo-2-Norbornyl and 1-adamantyl tosylates react with sodium phenoxide in tetrahydrofuran via ionization, most probably through a cyclic transition state.The results call for attention in interpreting substitution reactions under "apperently-SN2" conditions.
