| Abstract
| - A novel strategy for the construction of benzopyranyl heterocyclic series with maximized diversity inthe polar surface area on rigid scaffolds has been developed through a divergent synthetic pathway withhigh efficiency. s-cis-Enones embedded in a benzopyran skeleton were identified as versatile keyintermediates for the synthesis of four different heterocycle libraries fused with a benzopyran substructure.These four novel core skeletons were designed by a creative recombination of the privileged skeletons: benzopyran, pyridine, pyrazole, pyrazolopyrimidine, and pyrimidine. The regioselective synthesis of eachcore skeleton was achieved by the introduction of three s-cis enone intermediates. This paper also exploresthe regioselective formation of arylpyrazole through the condensation of β-keto aldehyde with arylhydrazineunder three different conditions and presents the mechanistic information that was obtained from theregioisomeric ratio of arylpyrazole based on the substituent's electronic effect and reaction temperature.It appears that the regioselective synthesis of arylpyrazole was achieved through the intriguing interplayof the nucleophilicity on arylhydrazine and the electrophilicity on dielectrophiles.
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