DFT studies on the base-facilitated direct coupling of carbon dioxide with 2,2-dimethyl-1,3-propanediol

DFT calculations to support the article 'Synthesis of 5-to 8- membered cyclic carbonates from diols and CO₂: a one-step, atmospheric pressure and ambient temperature procedure'<br>DFT study comprises:-DFT optimised geometries and computed enthalpies were used to calculate the thermodynamics and kinetics of the carbonation of 2,2-dimethyl-1,3-propanediol's alcohol moiety facilitated by NEt₃, TMP, pyridine and DBU into the hydroxyl via a ternary Lewis base-CO₂-diol mechanism. -DFT optimised geometries and computed enthalpies were used to calculate the thermodynamics and kinetics of the cyclisation of 4,4-dimethyl-7-oxo-7-(tosyloxy)heptanoate (BCI) to form 5,5-dimethyl-1,3-dioxan-2-one.-DFT optimised geometries and computed enthalpies were used to calculate the thermodynamics and kinetics of the NEt3-facilitated direct coupling of CO₂ with 2,2-dimethyl-1,3-propanediol to form 5,5-dimethyl-1,3-dioxan-2-one via three competitive mechanistic pathways. <br>Protocol:rωb97xD/6-31+g(d)/cpcm=acetonitrile/298K <br>Content:-Gaussian09 rev D.01 output files-CO2_insertion_comparison.pdf, illustrating the calculations made and summarising the enthalpies computed for NEt₃, TMP, pyridine and DBU into the hydroxyl group of 2,2-dimethyl-1,3-propanediol via a ternary Lewis base-CO₂-diol mechanism. -BCI_cyclisation.pdf, illustrating the calculations made and summarising the enthalpies computed for the cyclisation of BCI to form 5,5-dimethyl-1,3-dioxan-2-one- NEt3_mechanism, illustrating the calculations made and summarising the enthalpies computed for the direct coupling of CO₂ with 2,2-dimethyl-1,3-propanediol to form 5,5-dimethyl-1,3-dioxan-2-one via three competitive mechanistic pathways.<br>