Investigation on the reactivity of dithiophosphonato/dithiophosphato NiII complexes towards 2,4,6-tris-2-pyridyl-1,3,5-triazine: developments and new perspectives

Abstract

The reactions between tptz and differently substituted dithiophosphonato [Ni(ROpdt)2] [ROpdt = (RO)(4-MeOC6H4)PS2-; R = Et (2); Pr (3); i-Pr (4); Bu (5)] and dithiophosphato [Ni((EtO)2PS2)2] (6) Ni(II) complexes have been investigated, and the characterisation of the resulting neutral mixed complexes (2.tptz)-(6.tptz) is reported. In all these complexes, tptz forces one of the two dithiophosphonato/dithiophosphato ligands to behave as a monodentate ligand, a coordination mode rarely found in analogous Ni(II) phosphorodithioato complexes. A comparison has been performed between the Ni-S bond distances of the new complexes and those of isologous dithiophosphonato, dithiophosphato and dithiophosphito Ni(II) square-planar complexes, and of their penta- and hexa-coordinated adducts. The results, also supported by DFT calculations, are discussed and explained in terms of the structural trans-effect (STE). The reactivity of 2.tptz towards AgNO3 and CuSO4 to yield the complex [Ni(EtOpdt)(tptz)(H2O)]NO3 (7), and the dimer [(Ni(tptz)(mu-SO4)(H2O)]2.6H2O (8), respectively, is consistent with the proposed bonding models.

Multimetallic compounds containing cyclometalated Ir(III) units: Synthesis, structure, electrochemistry and photophysical properties

“…A rich chemistry of transition metal-tptz compounds has developed in recent years including their applications in supramolecular chemistry, electrochemistry and photophysics [42][43][44][45]. However, hydrolysis of tptz to bis-(2-pyridylcarbonyl)amide anion has been reported in the presence of Rh III in aqueous-alcohol solution [46,47].…”

Photochromism and Photomagnetism in Two Ni(II) Complexes Based on a Photoactive 2,4,6-Tris-2-Pyridyl-1,3,5-Triazine Ligand

“…49,50 This ligand, with multiple coordination sites, a large and stable π-conjugated system and luminescent property, can participate in the photochromic process as an electron acceptor and luminophore. 51,52 However, to the best of our knowledge, no photochromic TPTz-based complexes were reported.…”

“…On the other hand, rigid pyridine ligands, as suitable electron acceptors, can form intermolecular stacking interactions, stabilize photogenerated radicals, and further enrich and improve the photochromic properties of the built materials . As a rigid nitrogen-containing ligand, 2,4,6-tris-2-pyridyl-1,3,5-triazine (TPTz) has been widely used in the construction of coordination complexes. , This ligand, with multiple coordination sites, a large and stable π-conjugated system and luminescent property, can participate in the photochromic process as an electron acceptor and luminophore. , However, to the best of our knowledge, no photochromic TPTz-based complexes were reported.…”