Chiral Phosphapalladacycles as Efficient Catalysts for the Asymmetric Hydrophosphination of Substituted Methylidenemalonate Esters: Direct Access to Functionalized Tertiary Chiral Phosphines

A chiral palladacycle-promoted enantioselective asymmetric
hydrophosphination
of substituted methylidenemalonate esters using diphenylphosphine
that provides direct access to chiral tertiary phosphines is reported.
Screening of three easily accessible C,N and C,P palladacycles as
catalysts for this synthetic scenario provided insights into critical
factors in catalyst design that influence the activation and stereochemistry
in Pd­(II)-catalyzed asymmetric P–H addition reactions involving
such activated substrates.