Steric control of tritolylphosphines on the nuclearity of Cu(I) complexes: Syntheses and structures of the iodo-bridged [Cu4(μ3-I)4( p -tolyl3P)4] cubane and the [Cu2(μ-I)2( o -tolyl3P)2] dimer

The preparation and crystal structures of copper(I) iodide complexes with tri-o-tolylphosphine (o-tolyl(3)P) and tri-p-tolylphosphine (p-tolyl(3)P) are described. While p-tolyl(3)P forms an iodo-bridged cubane, [Cu4I4(p-tolyl(3)P)(4)]. 1, o-tolyl(3)P forms a dimer, [Cu2I2(o-tolyl(3)P)(2)], 2. In 1. each Cu is bonded to one P atom of p-tolyl(3)P {Cu- P, 2.248(2). 2.243(5) angstrom} and three iodide ligands {Cu I, 2.690(1), 2.686(2). 2.663(2) angstrom} I -Cu-I bond angles are in the range 67-70 degrees and Cu I Cu vary between 106 and 112 degrees. In 2, the central unit. Cu(mu-I)(2)Cu, forms a parallelogram With unequal Cu I distances {Cu 1, 2.601(1), 2.579(1)angstrom} and bond angles {Cu I-Cu, 74.42(3). I-Cu-I, 105.59(3)degrees}. Each Cu atom is further bonded to one P atom of o-tolyl(3)P {Cu P, 2.246(2) angstrom}.