Dynamic Copper(I) and Silver(I) Complexes of Tri‐ tert ‐butyl‐cyclotriphosphane

Abstract The reaction of cyclo ‐(P 3 t Bu 3 ) with Cu I and Ag I salts led to the di‐ and tetranuclear complexes [Cu n (μ‐Br) n {μ‐ cyclo ‐(P 3 t Bu 3 )‐κ P 1 ,κ P 2 } 2 ] with n  = 2 ( 1 ) and n  = 4 ( 2 ) and [Ag n (OTf) n (CH 3 CN) 2 n −2 {μ‐ cyclo ‐(P 3 t Bu 3 )‐κ P 1 ,κ P 2 } 2 ] with n  = 2 ( 4 ) and n  = 4 ( 5 ). Complexes 1 , 2 , 4 and 5 were isolated as crystalline powders or single crystals and characterized by X‐ray diffraction. In solution, these complexes exhibit a dynamic equilibrium which involves continuous dissociation and reforming of phosphorus−metal bonds leading to isomeric intermediates. This behavior was demonstrated by low‐temperature 31 P{ 1 H} NMR spectroscopy and the conclusions were corroborated by DFT calculations.