Enthalpies of formation of isoprene’s major oxidation byproducts

The theoretical enthalpies of formation ( Δ f H 298 . 15 ∘ ) of methyl vinyl ketone (MVK, CH2CHC(O)CH3), methacrolein (MACR, CH2C(CH3)CHO), and the radical products formed in their corresponding OH radical oxidations have been calculated with DFT (MPW1K/6-31+G(d,p)) and multilevel (MCCM-UT-CCSD(T)//MPW1K/6-31+G(d,p)) methods. The bond dissociation energies ( BDE , DH 298 . 15 0 ) of the H-atoms that can be abstracted from the MVK and MACR molecules, and the C–O forming bonds of the OH addition products are also calculated. The regioselectivity of the global reaction is discussed in terms of bond strength.