LAUSR

Abstract Tetracarbonylmolybdenum(0) complexes of the type cis-[Mo(CO)4(L)] containing chiral 7-(1-pyrindanyl) amine ligands were prepared and found to be effective precatalysts for the epoxidation of achiral (cis-cyclooctene) and prochiral (DL-limonene and trans-β-methylstyrene) olefins at 55 °C. Epoxides were the only products formed from cis-cyclooctene (100% yield) and trans-β-methylstyrene (100% selectivity at 82–85% conversion), and the main products formed from DL-limonene (80–82% 1,2-epoxide selectivity at 85% conversion). Characterization of recovered catalysts revealed that the precatalysts were transformed in situ to stable polyoxomolybdate salts containing the β-octamolybdate anion [β-Mo8O26]4−, which was responsible for the catalytic reaction.