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Study on new methodologies of heterocyclic synthesis has been one of the major activities of the synthetic organic chemist, aims not only at newer molecular framework generation, but also at addressing economic, environmental and ecological issues linked to the green chemistry. The objective of this book is to acquaint readers with many new pyran-heterocycles synthesized via domino/Knoevenagel-hetero-Diels-Alder approach which was improved in catalyst- and solvent-free, solvent-free tetrabutylammonium hydrogen sulfate (TBA-HS)-catalyzed and triethylammonium acetate(TEAA)-mediated conditions of reaction. As main highlights, the methodologies assure high atom efficiency, minimum energy usage, and catalyst use in the synthesis, which are the key green chemistry principles; number 1, 2, 6, and 9 respectively.

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Dr.Narsidas Parmaris working as Professor at Department of Chemistry, Sardar Patel University, Vallabh Vidyanagar. He joined the department in 1996 and received his Ph.D. degree in 2003 from the same institute. He published over 20 research papers in international journals of good repute and also worked on 3 UGC-funded research projects.

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