Kinetic Is otope EffectsInvest igationon the Mech anism of Nitrogen Extr usion from ۳-Methyl-۱-Pyrazoline

Curre ntly determining the transition state (TS) of reactions i n the gas and liquid phases becom es more interesting usi ng the femto -second pulses from th e experimental point of view. Theoretically, rec ent progress in comp uting device s such as CPUs and motherboards of comp uters in add ition to computing softwares is the second factorwhich accelerate s the kineti c and mecha nistic studi es. One class of the interesting reactions which may be occ urred in the gas phas e is the elimination reactions. For example nitrogen elimination from substituted ۱-pyrazolines in the gas phase is a unimolecular reaction in which two probable trajectories can be compete. This pyrol ysis reactio n is synthetically important becaus e the corresponding pro ducts are clean and further purifications is not needed. Since in this ty pe of pyroly sis H transfer may be take place i n the TS, k inetic isotope effects i nvestigation is of importance to det ermine the real mechanism. Due the course of reaction, secondary deuterium kineti c isotope effect and kH/ kD value were evaluated to determin e which one of the proposed mecha nisms is do minant.As the secondarydeuterium kinetic isotope effect offers a pow erful method for chara cterization o f the bondb reaking at the transition state (TS) of the pyrolysis reacti ons, the presented resea rch employs the deuteri um isotope instead of h ydrogen ato ms on some specific situations of the reactant.

کلیدواژه ها:

Mechanism ، Computational ، ۳-Methyl-۱-pyrazoline ، Transition St ate ، DFT