The Journal of Physical Chemistry

Gas-phase NMR studies of N, N-dimethylamides. Inter-and intramolecular contributions to internal rotation activation energies

BD Ross, LT Wong, NS True

Index: Ross, Brian D.; Wong, Leland T.; True, Nancy S. Journal of Physical Chemistry, 1985 , vol. 89, # 5 p. 836 - 839

Full Text: HTML

Citation Number: 28

Abstract

Temperature-dependent gas-phase'H NMR spectra of six C-substituted N, N- dimethylamides (XCON (CH,),) obtained at 500 MHz are consistent with the following free activation energies, AG* 298 (kcal/mol): X= C1, 15.4 (0.2); Br, 14.1 (0.2); N3, 16.5 (0.1); CN, 19.0 (0.1); CH2F, 15.2 (0.1); CHF2, 17.4 (0.1). For all of the amides studied, the observed first-order unimolecular rate constants are consistent with gas-phase AG* 298 values for ...