Synthesis and conformational aspects of 2-phenoxytetralones: Experimental verification and density functional theory (DFT) calculation

Abstract

A series of 2-phenoxy-1-tetralones have been synthesized as conformationally constrained analogs of bioactive compounds 2-phenoxyacetophenones. A representative oxime derivative of 2-(3-methoxyphenoxy)-1-tetralone was selectively prepared and its (Z)-geometry was characterized by proton nuclear magnetic resonance (1H NMR) spectroscopy. Also, the conformational aspects of designed compounds were investigated by 1H NMR spectroscopy and density functional theory (DFT) calculations. The computational results showed that the more stable conformation in 5c is a conformer with equatorial orientation for 2-aryloxy group but the axial orientation in the related oxime 6 is predominated. Accordingly, it was demonstrated that the formation of (Z)-oxime on 1-position results in a remarkable conformational inversion on tetralin ring.