Temperature Dependence of (+)-Catechin Pyran Ring Proton Coupling Constants as Measured by NMR and Modeled Using GMMX Search Methodology

The pyran ring proton coupling constants for (+)-catechin have been experimentally determined in deuterated methanol over a temperature range of 213 K to 313 K. The experimental coupling constants were simulated to 0.04 Hz on the average at a 90% confidence limit using LAOCOON method. The temperature dependence of the coupling constants was reproduced from the Boltzmann distribution of theconformational ensemble generated by the GMMX searching program.