Palladium−Duphos Structural and Enantioselective Hydroarylation Chemistry

A series of Pd(II) complexes of 1,2-bis((2 R,5 R )-2,5-dimethylphospholano)benzene (MeDuphos; 1 ) have been prepared, and the solid-state structures for five of these, PdBr( p -CN-C 6 H 4 )( 1 ), PdX(C 6 F 5 )( 1 ) (X = Br, I), Pd(OAc) 2 ( 1 ), and [Pd(CH 3 CN) 2 ( 1 )](PF 6 ), have been determined by X-ray diffraction. Several of these complexes are catalyst precursors for the enantioselective hydroarylation of norbornene with PhX (X = Br, I, OTf). The maximum ee, 75%, is higher than the corresponding values previously reported for bidentate phosphine auxiliaries. NOESY NMR results show how complexed 1 interacts with the aryl ligand in PdBr( p -CN-C 6 H 4 )( 1 ).