Nitrogen-Assisted Ortho Lithiation: One-Pot Synthesis of New Classes of Bidentate and Tetradentate Mixed P∼N Ligands

Metalation of one aryl group of Ph3PNR (R =
methyl, isopropyl) affords an easy access to the corresponding
lithium salt, which in turn reacts with chlorophosphines R2PCl
(R = Ph, i-Pr) to yield a new class of bidentate ligand featuring
one iminophosphorane and one phosphino group. Reaction of
the phenyl derivative with [Pd(COD)Cl2] yielded the expected
six-membered palladacycle complex, which was structurally
characterized. Extension of this new synthetic methodology
toward the elaboration of enantiomerically pure tetradentate
ligands has also been achieved.