Tertiary phosphine‐appended transition metal ferrocenyl dithiocarbamates: Syntheses, Hirshfeld surface, and electrochemical analyses

Abstract

Five new heteroleptic complexes of Cu(I), Ag(I), and Ni(II) having formulae [Cu3(dtc)2(dppf)2]PF6 (Cu‐I), [Cu3(dtc)2(dppe)2]PF6 (Cu‐II), [Cu(PPh3)2(dtc)] (Cu‐III), [Ag3(dtc)2(PPh3)2]NO3 (Ag‐I), and [Ni(dtc)(dppf)]PF6 (Ni‐I) (dtc = N‐ethanol‐N‐methylferrocenyl‐dithiocarbamate; dppf = 1,1′‐bis(diphenylphosphino)ferrocene; dppe = 1,1′‐bis(diphenylphosphino)ethane; PPh3 = tripheylphosphine) have been synthesized and characterized using elemental analysis, Fourier‐transform infrared, multinuclear nuclear magnetic resonance, UV–Vis spectroscopy, and single‐crystal X‐ray diffraction. The single‐crystal X‐ray diffraction studies indicate that Ag‐I forms a rare trinuclear cluster in which the geometry around the two silver centers Ag1 and Ag3 is distorted tetrahedral, whereas the third silver center Ag2 shows a distorted trigonal planar geometry. The Ni‐I complex has a distorted square‐planar geometry around the Ni center. In addition, a side product [Ag2{S2(dppf)2}] (Ag‐II) was obtained during an attempt to synthesize [Ag(dppf)(dtc)], where the two Ag centers are bridged by two sulfido centers and coordinated with two phosphorus centers of the dppf ligand to give rise to a distorted tetrahedral geometry. The solid‐state structures of Ag‐I, Ni‐I, and Ag‐II are stabilized by a variety of weak interactions. The nature of these interactions has been addressed with the help of Hirshfeld surface analyses. In addition, the weak argentophilic interaction in Ag‐I and Ag‐II have been studied using quantum theory of atoms in molecules and natural bond orbital calculations. The electrochemical properties of the complexes have been investigated using cyclic voltammetry, where Cu‐I and Cu‐II exhibited two quasi‐reversible waves, whereas Cu‐III, Ag‐I, Ag‐II, and Ni‐I exhibited only one quasi‐reversible peak.