Application Of New Ligands Research Articles

Iridium-catalyzed oxidative olefination of furans with unactivated alkenes.

The oxidative coupling of arenes and alkenes is an attractive strategy for the synthesis of vinylarenes, but reactions with unactivated alkenes have typically occurred in low yield. We report an Ir-catalyzed oxidative coupling of furans with unactivated olefins to generate branched vinylfuran products in high yields and with high selectivities with a second alkene as the hydrogen acceptor. Detailed mechanistic experiments revealed catalyst decomposition pathways that were alleviated by the judicious selection of reaction conditions and application of new ligands.

Asymmetric molybdenum(0)-catalyzed allylic substitution

Application of new ligands ( R)-(−)- 8 , ( S)-(+)- 16 , and ( S)-(+)- 17 to the title reaction ( 1 or 2 → 3 ) led to excellent regio- and enantioselectivities (>30:1; ≤98% ee); although lacking the C 2-symmetry, the catalysts can be viewed as quasi- C 2-symmetrical since the single chiral center is sufficient to determine the sense of wrapping of the metal by the ligand.