Thermochemistry of Furan and Its Derivatives: A High-Level Ab Initio Study

The standard molar enthalpies of formation in the gas phase at T = 298.15 K for 43 furan derivatives were calculated using the DLPNO-CCSD(T-1)/CBS method in conjunction with isodesmic-type reactions to assess the accuracy of experimental data reported in the literature. The high accuracy of the experimental data was confirmed for almost half of the studied compounds (44%). For the remaining furans, the discrepancy between the experimental and theoretical values is larger than 5-70 kJ<middle dot>mol(-1), and additional experimental measurements are obviously required to determine more accurate values of the enthalpy of combustion and/or enthalpy of phase change. The experimental enthalpies of formation of 12 furans are recommended as benchmark reference values for use in thermochemical calculations of furan-based compounds.