Allyl, olefin, aryl and alkyl organometallic palladium complexes of 1,2-bis[(2R,5R)-2,5-dimethylphospholanyl]benzene

Abstract

A series of organometallic chiral complexes of palladium containing the chelate Duphos, 1,2-bis[(2R,5R)-2,5-dimethylphospholanyl]benzene 1, have been prepared. These include the 1,3-diphenylallyl cationic compound, [Pd(PhCHCHCHPh)(1)][CF₃SO₃] 2, the palladium(0) fumaronitrile complex [Pd(NCCHCHCN)(1)] 3, and the pentafluorophenyl derivatives [Pd(R)(C₆F₅)(1)] (R = Me 4a, Et 4b, or Bu 4c). The solid-state structures of 2 and 4a have been determined by X-ray diffraction. The structure of complex 4a deviates markedly from the expected square planar geometry. Duphos 1 affords a ca. 98% enantiomeric excess in the enantioselective allylic alkylation reaction of a 1,3-diphenylallyl precursor. Detailed ¹H and ¹³C NMR results are reported.