title: Theoretical study on reaction mechanism of the fluoromethylene radical with nitrogen dioxide.
abstract: The complex doublet potential energy surface for the reaction of 1CHF with NO2, including 14 minimum isomers and 30 transition states, is explored theoretically at the B3LYP/6-311G(d,p) and CCSD(T)/6-311G(d,p) (single-point) levels of theory. The initial association between 1CHF and NO2 is found to be the carbon-to-middle-nitrogen attack forming an energy-rich adduct a (HFCNO2) with no barrier, followed by concerted O-shift and C--N bond rupture leading to product P2 (NO + HFCO), which is the most abundant. In addition, a can take a 1,3-H-shift to isomer b (FCN(O)OH) followed by the dissociation to form the second feasible product P4 (OH + FCNO). The least favorable pathway is that b undergoes a concerted OH-shift to form d (HO(F)CNO), which will dissociate to product P5 (HF+OCNO) via side HF-elimination. The secondary dissociation of P5 may form product P7 (HF+NO+CO) easily. Furthermore, the 1CHF attack at the end-O of NO2 is a barrier-consumed process, and thus may only be of significance at high temperatures. The comparison with the analogous reactions 1CHCl + NO2 is discussed. The present study may be helpful for probing the mechanism of the title reaction and understanding the halogenated carbine chemistry.
authors.affiliation: Institute of Theoretical Chemistry, State Key Laboratory of Theoretical and Computational Chemistry, Jilin University, Changchun 130023, People's Republic of China.
authors.forename: Jia-Xu
authors.initials: JX
authors.lastname: Zhang
authors.forename: Jing-Yao
authors.initials: JY
authors.lastname: Liu
authors.forename: Ze-Sheng
authors.initials: ZS
authors.lastname: Li
authors.forename: Chia-Chung
authors.initials: CC
authors.lastname: Sun