Group 11 Complexes of theP,Te-Centered Ligand [TePiPr2NPiPr2]−: Synthesis, Structures, and Insertion Reactions of the Copper(I) Complex with Chalcogens

Abstract

The lithium reagent [LiTeP(i)Pr(2)NP(i)Pr(2)] undergoes metathetical reactions with group 11 chlorides to give the complexes {M(TeP(i)Pr(2)NP(i)Pr(2))}(3) (6: M = Cu; 7: M = Ag) and (Ph(3)P)Au(TeP(i)Pr(2)NP(i)Pr(2)) (8) as yellow crystalline solids. These new complexes were characterized by single crystal X-ray diffraction and multinuclear NMR spectroscopy. The tellurium atoms in the trimeric complexes 6 and 7 occupy bridging positions to give a Cu(3)Te(3) ring in a twist-boat conformation with short M...M contacts (M = Cu, Ag). Variable temperature (31)P NMR and ESI-MS spectra for 6 and 7 give evidence for the formation of several oligomers in tetrahydrofuran solution. The reactions of 6 with dioxygen (or Me(3)NO), elemental sulfur, or red selenium generate the chalcogen-insertion products {Cu(TeP(i)Pr(2)NP(i)Pr(2)E)}(3) (9: E = O; 10: E = S; 11: E = Se), which were also structurally characterized by single crystal X-ray diffraction and multinuclear NMR spectroscopy. The lighter chalcogens are two-coordinate while the tellurium centers occupy bridging positions in the trimeric complexes 9-11 giving rise to Cu(3)Te(3) rings in a chairlike conformation.