Conformational free energy (ΔG value) of the amino-group in cyclohexylamine from low temperature carbon-13 nuclear magnetic resonance spectroscopy
Abstract
The carbon-13 n.m.r. spectrum of cis-4-methyl-cyclohexylamine, measured at –75°C, reveals signals for both possible chair conformations, and the measured ratio of 1·95 to 1 leads to a value of 6·05 ± 0·17 kJ mol–1 for ΔG(NH2).