The hydridotris(3-nitro-1,2,4-triazol-1-yl)borate, a new nitro-substituted electron withdrawing polydentate “scorpionate”-type ligand and related copper and silver phosphane complexes

Abstract

The new tripodal “scorpionate”-type ligand, the sodium hydridotris(3-nitro-1,2,4-triazol-1-yl)borate Na[HB(tzNO2)3] (1), containing electron withdrawing nitro functional groups on the azolyl moiety, has been synthesized in high yield starting from 3-nitro-1,2,4-triazole and sodium borohydride. New copper(I) and silver(I) complexes, [HB(tzNO2)3]M(PR3)2 (M = Cu or Ag; PR3= P(C6H5)3, or P(p-C6H4CH3)3) have been synthesized from the reaction of CuCl or AgNO3 with Na[HB(tzNO2)3] and triphenylphosphane or tri(p-tolyl)phosphane, respectively. These compounds have been characterized by elemental analyses, FT-IR, ESI-MS and multinuclear NMR spectroscopy. X-ray crystal structure of Na[HB(tzNO2)3] (1) shows that it has polymeric network structure resulting from sodium atoms of tripodal Na[HB(tzNO2)3] forming inter-molecular Na-N bonds to three nitrogen atoms of three neighboring triazolyl moieties of Na[HB(tzNO2)3]. Each sodium center has distorted octahedral geometry with three short Na-N (inter-molecular) and three long Na-N bonds (to chelating N-atoms of [HB(tzNO2)3]- ligand). This nitro-substituted scorpionate ligand could be of interest due to its high coordinative flexibility from endo- to exo-polydentate coordination mode

Crystal structure of a Zn complex with terephthalate and 1,6-bis(1,2,4-triazol-1-yl)hexane

“…One of the favoured classes of bitopic ligands are bis(azol-1-yl) alkanes, which have been used for the preparation of various transition metals coordination polymers with different topologies (Alkorta et al, 2017;Pellei et al, 2017;Manzano et al, 2016;Liu et al, 2012). Bitopic bis(azol-1-yl)alkanes have two separated metalbinding sites that allow them to form a wide variety of polymeric structures.…”

Design of New Bis(1,2,3‐triazol‐1‐yl)methane‐Based Nitrogen Ligands: Synthesis and Coordination Chemistry

“…The use of ligands based on bis(triazol‐1‐yl)methane moieties in coordination chemistry has been scarcely reported. Bis(1H‐1,2,4‐triazol‐1yl)acetic acid and bis(2H‐benzotriazol‐2‐yl)acetic acid were the first ligands of this class reported, and their Ru, Mn, Cu and Ni complexes have found use in the synthesis of metal‐organic frameworks (MOF), in medicinal chemistry as mimics of the active site of metalloenzymes, as radiopharmaceuticals and anticancer agents [25‐30] . More recently, acetamidate and thioacetamidate heteroscorpionate ligands based on the bis(triazol‐1‐yl)methane moiety have been used for the synthesis of organometallic zinc compounds (Scheme 2).…”

Low- and Mid-Valent Uranium Species Supported by Phenyltris(oxazolinyl)borate Ligands

“…Scorpionate ligands, first popularized by Trofimenko, have been used on virtually every metal on the periodic table. − While these ligands are named for their tridentate coordination mode, scorpionates are considered to be analogous to cyclopentadienes, as both are monoanionic, six-electron donors (ionic model) and three-coordinate (one σ bond, two π bonds). In the years since the report of Trofimenko’s poly­(pyrazolyl)­borate ligands, − , there have been many variations of this framework developed, including substituted poly­(pyrazolyl)­borate, , poly­(triazolyl)­borate, − poly­(tetrazolyl)­borate, , poly­(imazoyl)­borate, and poly­(alkyl phosphinyl)­borate ligands, , to tailor the steric and electronic properties of the resulting coordination complexes.…”