Synthesis of a new tetradentate bis(imino-phosphine) ligand and its complexation with copper(I) ions

Schiff base condensation of m-phenylenediamine with two equivalents of o-(diphenylphophino)benzaldehyde products the potentially tetradentate molecule 1,3-(Ph2P(o-C6H4)CHN)2C6H4 (1) in high yield. The reaction of 1 and [Cu(NCMe)4]BF4 affords the dinuclear complex [(1,3-(Ph2P(o-C6H4)CHN)2C6H4)2Cu2](BF4)2 (2) through coordination of the imino-phosphine groups. The structure of 2 has been determined by an X-ray diffraction study.