Abstract

Numerous 6π conjugated systems were observed during an electrocyclization-condensation reaction in order to understand resonating electrons behave in π-orbitals in the presence of withdrawing and donating substituents. The prediction that when the 6π carbanion system contains a withdrawing or deactivating residue, the density of the π-electrons will be delocalized, causing the π-electrons to be more organized and stabilizing the system. Under the notions of foundation carbanion and resonance theory, the stabilization of the carbanion system will decrease the reaction entropy, as well as hindering product formation, thus resulting in a decrease in yield under a specific time frame. In turn, We predict that donating or activating residues will contribute to a less stable, more electron dense and more entropic intermediate and these cause product formation to occur in relatively higher yields than the former case described. The electrocyclic-condensation of glycine-ethyl or metyhhyl ester hydrochloride and chalcone derivatives with varying electronic substituents is being observed and performed. In the reaction, the chalcone and glycine- ethyl ester condensed to form a secondary imine intermediate. In the same pot, this intermediate underwent an electrocyclization forming a dihydro-pyrrole. Several novel α-substituted chalcones were synthesized in good to excellent yield using a variety of methods. It was found that the specific dihydropyrrole formed was dictated by the alpha-substituent. Thus far some α-chalcones formed C-N pi bonded dihydropyrroles, whereas other α-substituted chalcones generated N-H dihydropyrroles other dihydropyrroles are being developed and the results will be reported in the future. Trends associated with the reaction of these α-substituted chalcones with various withdrawing or donating residues with glycine ethyl or methyl ester in the pyrrole formation process are provided

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