Chiral Ruthenium Complex for Enantioselective Cyclopropanations

Ru(II)-(S)-Pheox Catalyst (1) is a chiral phenyloxazoline-ruthenium(II) complex, developed by Iwasa et al.
1 catalyzes highly enantioselective cyclopropanation of various olefins using diazoacetates^1-6,8) or diazomethylphosphonates.^7,8) In addition, 1 is also used for an enantioselective Si–H insertion reaction of α-diazo esters.⁹⁾ 1 is a promising reagent for the synthesis of medicinally relevant optically active cyclopropane derivatives.