title: Investigation on the reactivity of dithiophosphonato/dithiophosphato Ni(II) 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.
authors.affiliation: Dipartimento di Chimica Inorganica ed Analitica, Università degli Studi di Cagliari, S.S. 554 bivio per Sestu, 09042, Monserrato-Cagliari, Italy. aragoni@unica.it
authors.forename: M Carla
authors.initials: MC
authors.lastname: Aragoni
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Arca
authors.forename: Miriam
authors.initials: M
authors.lastname: Crespo
authors.forename: Francesco A
authors.initials: FA
authors.lastname: Devillanova
authors.forename: Michael B
authors.initials: MB
authors.lastname: Hursthouse
authors.forename: Susanne L
authors.initials: SL
authors.lastname: Huth
authors.forename: Francesco
authors.initials: F
authors.lastname: Isaia
authors.forename: Vito
authors.initials: V
authors.lastname: Lippolis
authors.forename: Gaetano
authors.initials: G
authors.lastname: Verani