The study of the titled reaction has been carried out using high-level quantum mechanics in conjugation with SCTST and VPT2 model. The many quantum mechanical methods have been employed in combinatory approach to find out the various properties such as energy, anharmonic vibrational coefficients and ro-vibrational parameters for the stationary points including the transition state of the reaction. Then the thermal rate coefficients were computed over a temperature regime of 150-1500 K and the corresponding results were compared with the available literature. In this temperature regime, our computed results are in excellent contrast with the experiment. (C) 2016 Elsevier B.V. All rights reserved.