Computational Study of Chemical Reactivity of Vinylpyrrole Derivatives

Abstract

The electrostatic potential V (r) and the average local ionization energy. I (r) are discussed as a measure for the chemical reactivity of 2—and 3-vinylpyrrole and their 1-methy1-2-or 4-fonnyl de'rglatives. A survey of applications of DPT and ab initio SCF I (r) computed on molecular surfaces defined by 0.001 au contour of the electronic density p (r) was presented as a tool of chemistry. The minima of both properties, VS, min and 15,111 in were located and determined. Also, the energy gaps (LUMOdienophiles' HOMopyrrol) were calculated, for three possible dienophiles and the pyrrole derivatives. AM ll/HF/3—21G based wavefunction was generated to map both HOMO and LUMO of the derivatives to compare their relative sizes. The electronic calculations showed that the 2-formyl-1-methy1-4-viny1pyrrole, as a diene, is more reactive toward dienophiles than the 4-formyl-1-methyl-2-vinylpyrrole. The mapped orbitals …