Comparison of Thermodynamic Hydrogen Bonding, Brönsted and Gas-phase Basicity with Spectroscopic Hydrogen Bonding Basicity of N1,N1-Dimethylformamidines. Similarities and Differences in Substituent Effects
Abstract
Comparison of the thermodynamic (logKHB with 4-fluorophenol in CCl4, pKa in azeotropic ethanol and GB in the gas phase) with spectroscopic basicities (ΔvOH of methanol in CCl4) for N1,N1-dimethylformamidines shows good correlation only between the pKa and ΔvOH values; no general simple linear model can be applied to the logKHB/ΔvOH and GB/ΔvOH relations.