Fig. 3. DFT calculations of acylation of 2-MF with acetic acid.

All the values are reported in kilojoules per mole. The transition states are shown as the insets with C, O, H, Si, and Al atoms colored cyan, red, gray, black, and green, respectively. The results calculated using the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional (red) are also shown, for comparison with the PBE results (black). The reaction path is schematically shown at the bottom.