Trialkylphosphine-Stabilized Copper(I) Phenylchalcogenolate Complexes - Crystal Structures and Copper–Chalcogenolate Bonding

A series of trialkylphosphine-stabilized copper(I) phenylchalcogenolate complexes [(R3P)m(CuEPh)n] (R = Me, Et, iPr, tBu; E = S, Se, Te) has been prepared and structurally characterized by X-ray diffraction. Structures were found to be mono-, di-, tri-, tetra-, hexa-, hepta-, or decanuclear, depending mainly on size and amount of phosphine ligand. Several structural details were observed, including unusually long Cu–E bonds or secondary Cu--E connections, μ4-bridging, and planar bridging chalcogenolate ligands. Relatively rigid Cu–E–C angles were found to be of significant influence on the flexible molecular structures, especially for bridging chalcogenolate ligands, since in these cases a correlation results between the Cu–E–Cu angles and the inclination of the E–C bonds to their Cu–E–Cu planes. We further address some of these phenomena by means of density functional computations.