Synthesis, characterization, and catalytic application of a new chiral P,N-indene ligand derived from (R)-BINOL

Lithiation of 2-dimethylaminoindene followed by quenching with [(R)-(1,1′-binaphthalene-2,2′-diyl)]chlorophosphite and treatment with triethylamine afforded the crystallographically characterized enantiopure P,N-indene 3 in 71% isolated yield. In the course of rhodium coordination chemistry studies involving 3, the formation of the isolable complex [(κ2-P,N-3)(κ1-P,N-3)RhCl] (7) (81%) was observed, thereby confirming the propensity of this new ligand to form LnRh(3)2 complexes. Such coordination chemistry behavior may contribute in part to the generally poor catalytic performance exhibited by mixtures of 3 and rhodium precursor complexes in the asymmetric hydrogenation and hydrosilylation studies described herein.