An Unsymmetric Imino-Phosphanamidinate Ligand and its Y(III) Complex: Synthesis, Characterization, and Catalytic Hydroboration of Carbonyl Compounds.

An imino-phosphanamide ligand, [NHIP(Ph)NH-2,6-PrCH] (), containing two different -substituents was prepared by the direct reaction of the lithium salt of -heterocyclic imine (NHI) with phenylchloro-2,6-diisopropylphenyl phosphanamine, PhP(Cl)NH-2,6-Pr-CH. Reaction of with Y(N(SiMe)) afforded the heteroleptic complex, [{L}Y(N(SiMe))] (), by elimination of HN(SiMe). Compound was characterized by multinuclear NMR and X-ray crystallography. In the complex, the Y(III) center was found to be tetracoordinate in a distorted tetrahedral geometry. The ligand, imino-phosphanamidinate, [L], functions in a chelating manner, and its coordination to Y(III) results in a distorted 4-membered YPN ring. As a proof of principle of its activity, was used as a precatalyst for the hydroboration of various aldehydes and ketones using HBpin as the hydrogen source. The hydroboration reaction was rapid and clean even with low catalyst loadings (0.01-0.1 mol %). In addition, a very good functional group tolerance was observed in these reactions.