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, [Cu4(C9H11)4(C3H9P)2] or [Cu4(Mes)4(PMe3)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 {Cu4C4} ring. Additionally, two copper(I) atoms at opposite corners of the Cu4 rhomb are each linked to a terminal PMe3 ligand. The PMe3-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.