Theoretical studies on the reaction mechanism of HNCS with CH2CH radical

The reaction mechanisms of HNCS with CH2CH radical have been investigated by density functional theory (DFT). The geometries and harmonic frequencies of the reactants, intermediates, transition states and products have been calculated at the B3LYP/6-311++G(d,p) level. The results show that the reaction is very complicated. Nine possible reaction pathways were identified. The results show that the most feasible reaction channel is the hydrogen-transfer pathway CH2CH + HNCS -> IMA1 -> TSA1 -> CH2CHH+ NCS. The pathway VIC C-S addition channel (CH2CH+ HNCS -> TSD5 -> IMD4 -> TSD9 -> CH2CHS + CNH) can also occur easily. Ethene and radical NCS is the main product of the studied reaction, and product P8 (CH2CHS and CNH) may also be observed. Compared with our previous study on the reaction HNCS + CH2CH, the present reaction is easier to proceed.