Planar chiral arene ruthenium complexes derived from R-carvone

Abstract

Natural R-carvone was converted into chiral 1-aryl-2-methyl-5-isopropyl-cyclohexadienes using cross-coupling reaction as a key step. These dienes react with RuCl3 to give planar-chiral complexes [(arene)RuCl2]2 in 70-75% yield. Complex [(1-Ph-2-Me-5-iPr-C6H3)RuCl2]2, a chiral analogue of the classical catalyst [(cymene)RuCl2]2, promotes C−H activation of N-methoxy-benzamide and intramolecular insertion of diazo compound into C−H bond, but gives products with low stereoselectivity.