Synthesis of Chalcones from Acetone and tetrazole and 2-acetyl naphthalene Assisted by Microwave

Abstract

In the present study, we understood the total synthesis one chalcone derivative via Claisen-Schmidt condensation of the respective aldehydes and ketones using Microwave assisted irradiation method. In the microwave environment, chemical reactions usually proceed faster and give higher yields with fewer by- products. In the synthesis, a common aldehyde namely tetrazolo {1, 5-a} quinoline-4-carbaldehyde was used while the ketones used were respectively acetone, 2- acetyl Naphthalene. The Chalcone synthesised from Tetrazolo {1, 5-a} quinolone-4-carbaldehyde and acetone was 4-(tetrazolo {1, 5-a} quinoline-4-yl) but -3-en-2-one. The Chalcone synthesised from Tetrazolo {1, 5-a} quinoline-4-carbaldehyde and 2-acetyl Naphthalene was 2E-1-(naphthalene-2-yl)-3-(tetrazolo {1, 5-a} quinolone-4-yl) prop-2-en-1- one. The starting aldehyde was Tetrazolo {1, 5-a} quinoline-4-carbaldehyde necessary for the Claisen-Schmidt condensation was in turn synthesized from Acetanilide which and Vilsmeier reagent (DMF and PoCl3) to produce the intermediate compound 2-chloroquinoline-3-carbaldehyde. This intermediate 2-chloroquinoline-3-carbaldehyde was then treated with sodium azide and acetic acid with ethanol as solvent to produce Tetrazolo {1, 5-a} quinoline-4-carbaldehyde. Structure of the compound were confirmed by spectral data such as IR and 1H-NMR.