A Dicoordinate Palladium(0) Complex with an Unusual Intramolecular η-Arene Coordination

The reaction of (tmeda)PdMe2 with dcpBiph gives (dcpBiph)2Pd in high yield. The solid-state structure of (dcpBiph)2Pd reveals a bent P-Pd-P framework and an unusual eta1-arene interaction between the palladium and the distal ring of one of the biphenyl substituents. In solution, an additional conformer exists which does not show a pi-interaction with a biphenyl ring. The low-coordinate complex, (dcpBiph)2Pd, undergoes C-X oxidative addition reactions with PhX (X = I, Br, Cl). A minor product resulting from metalation of the biphenyl ring is also observed.