The preparation and isolation of the first palladium dihydrogen complex is described. NMR spectroscopy reveals a very short H-H bond length, but the hydrogen molecule is activated toward heterolytic cleavage. An X-ray crystal structure suggests that proton transfer to the (tBu) PCP (κ(3)-2,6-((t)Bu2PCH2)2C6H3) pincer ligand is possible. The basicity of the ipso-carbon atom of the pincer ligand was investigated in a related complex.

Abstract:The preparation and isolation of the first palladium dihydrogen complex is described. NMR spectroscopyr eveals av ery short H À Hb ond length, but the hydrogen molecule is activated towardh eterolytic cleavage.A nX -ray crystal structure suggests that proton transfer to the tBu PCP (k 3 -2,6-( t Bu 2 PCH 2 ) 2 C 6 H 3 )p incer ligand is possible.T he basicity of the ipso-carbon atom of the pincer ligand was investigated in ar elated complex.