cyclo-Tetra-kis-(μ-2,4,6-tri-methyl-phenyl-κC (1):κC (1))bis-(tri-methyl-phosphane)-1κP,3κP-tetra-copper(I).

The title compound, [Cu(4)(C(9)H(11))(4)(C(3)H(9)P)(2)] or [Cu(4)(Mes)(4)(PMe(3))(2)] (Mes = 2,4,6-tri-methyl-phenyl), was synthesized from copper(I) mesityl and tri-methyl-phosphane in THF as solvent. The mol-ecular structure of the complex has C (2) symmetry and consists of four copper(I) atoms bridged by four μ-mesityl groups, giving an eight-membered puckered {Cu(4)C(4)} ring. Additionally, two copper(I) atoms at opposite corners of the Cu(4) rhomb are each linked to a terminal PMe(3) ligand. The PMe(3)-bearing copper(I) atoms exhibit a distorted trigonal-planar coordination mode whereas the remaining Cu atoms linked to two mesityl groups are nearly linearly coordinated.