Atmospheric reaction of OH radicals with 2-methyl-3-buten-2-ol (MBO): Quantum chemical investigation on the reaction mechanism

The reaction mechanisms of OH radicals with MBO in the presence of O2 and NO have been extensively investigated at the CCSD(T) method with geometries optimized at the MP2(full)/6-311+G(d,p) level. The ab initio calculations show that the title reaction occurs predominantly via initial additions of OH radicals to the two unsaturated C atoms of MBO. Under atmospheric conditions, the primary product pathway for OH + MBO is the formation of CH2OHCHO (P9) + CH3COCH3 (P10), and HCHO + (CH3)2COHCHO (P8) is the secondary one, which are in agreement with the experimental results. The reaction mechanism of yielding these products established in this study is different from previous expectation and the reason for this discrepancy has been discussed.