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A novel racemic tertiary amine, 1-(2,5-diisopropylphenyl)-N,N-dimethylethanamine, was synthesizedfrom 2,5-diisopropylbenzaldehyde via a multistep approach in highoverall yield. The ortho palladation of this ligand was found to besensitive to the reaction conditions and the palladating reagentsemployed. The metal complexation process could thus generate a cyclopalladatedcomplex in high yield, lead to an unexpected N-demethylated aminepalladium(II) complex, or both. Both products have been isolated andcharacterized crystallographically in the solid state and spectroscopicallyin solution. The racemic cyclopalladated complex could be efficientlyresolved via the formation of (S)-prolinato derivatives.The absolute stereochemistries of the resolved diastereomeric complexeswere determined by single-crystal X-ray crystallography in the solidstate and by 1H–1H rotating frame Overhausereffect (ROESY) NMR spectroscopy in solution. An evaluation of thesterically hindered resolved cyclopalladated units as chiral auxiliarieswas conducted in the endo-cycloaddition reaction between 3,4-dimethyl-1-phenylphosphole(DMPP) and ethyl vinyl ketone. The two expected phosphanorborneneadducts were generated with moderate stereoselectivity. [ABSTRACT FROM AUTHOR]

A chiral palladacycle-promoted enantioselective asymmetrichydrophosphinationof substituted methylidenemalonate esters using diphenylphosphinethat provides direct access to chiral tertiary phosphines is reported.Screening of three easily accessible C,N and C,P palladacycles ascatalysts for this synthetic scenario provided insights into criticalfactors in catalyst design that influence the activation and stereochemistryin Pd(II)-catalyzed asymmetric P–H addition reactions involvingsuch activated substrates. [ABSTRACT FROM AUTHOR]