2nd European Organic Chemistry Congress

Biography

Biography: Xavier J Salom-Roig, Erwann Grenet and Jean Martinez

Abstract

A Nazarov cyclization of activated dienones bearing a dihydropyran as an electron-donating group (EDG) and a chiral sulfoxide group as an electron-withdrawing group (EWG) and as a chiral inductor is described. The direction of the torquoselectivity highly depends on the nature of the Lewis acid promoter. This diastereodivergent strategy furnishes each trans stereoisomers from a common precursor. The scope of the reaction was extended to substrates bearing a phenyl and an activated aromatic or heteroaromatic moieties as an EDG. The corresponding Nazarov products are precursors of 3-aryl substituted cyclopenta[b]pyranone, indanone, pyrrole-fused and furan-fused cyclopentanone scaffolds, which are frequently encountered in many natural products such as sterhirsutins A and C, (+)-pauciflorol and the strigolactone analogue (±)-ST362. Thus, we report the first enantioselective synthesis of two 3-aryl substituted indanones known by their anticancer activity. The synthetic utility of this methodology was also highlighted by the transformation of the Nazarov cyclized products into highly functionalized cyclopenta-fused oxacycle-based scaffolds. As an example, the cyclopentene carbonyl group could be reduced stereoselectively in the corresponding cyclopentenols.