31991-53-4Relevant academic research and scientific papers
34. Norbornanes Part 20 Inductivity and Bridging in 2-Norbornyl Cations
Bielmann, Rolf,Fuso, Francesco,Grob, Cyril A.
, p. 312 - 319 (2007/10/02)
The solvolysis rates and products of several 1-substituted 2-exo- and 2-endo-norbornyl p-toluenesulfonates 7 and 8, respectively, have been determined.Hydrolyses of these epimeric tosylates yielded rearranged products in varying amounts, except when the substituent was COOCH3 or CN.The logarithms of the rate constants (log k) for the endo-series 8 correlated linearly with the corresponding inductive constants ?q1 with a reaction constant ρ1 of -1.24.On the other hand, log k values for the exo-series 7 appear to fit two regression lines,the first line (ρ1 = -1.90) defined by the tosylates that ionize, with rearrangement, to the tertiary cations 11, the second (ρ1 = -1.86) by the tosylates 7(R = H, COOCH3, and CN) that ionize to an asymetrically bridged secondary cation 19.These results confirm the unique participation of C(6) with a ρ1 of -2.00 in the ionization of 2-exo-norbornyl tosylate.
Synthesis and 13C NMR Analysis of a Series of Bridgehead-Substituted Polycycloalkanes: 13C-Labeled Methyl as the Substituent
Della, Ernest W.,Pigou, Paul E.
, p. 1085 - 1092 (2007/10/02)
The synthesis of eight polycycloalkanes substituted at the bridgehead with a 13C-labeled methyl group is described .Their 13C nuclear magnetic resonance spectra have been measured and the various NMR parameters are reported.It is found that there is no li
