A Ternary Nickel(II) Schiff Base Complex Containing Di-Anionic and Neutral Forms of a Dithiocarbazate Schiff Base

Yusof Yusof,Tiekink Tiekink,Nasri Nasri,Ravoof Ravoof

doi:10.3390/m1057

Yusof Yusof, Tiekink Tiekink + Show 2 more

Open Access

https://doi.org/10.3390/m1057

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Abstract

The title NiII complex, Ni(L)(LH2) (1), where LH2 is S-2-methybenzyl-β-N-(2-hydroxy-3-methoxybenzylmethylene) dithiocarbazate, was isolated from the reaction of Ni(acetate)2·4H2O and two molar equivalents of LH2. The complex was characterized by elemental analysis, spectroscopy (IR and UV) as well as by a single-crystal X-ray structure determination. The nickel(II) center is coordinated within a cis-NOS2 donor set that defines a square planar geometry. Three donor atoms, i.e., N, O, and S, are provided by a doubly deprotonated S-2-methybenzyl-β-N-(2-hydroxy-3-methoxybenzylmethylene) dithiocarbazate ligand while the fourth donor, i.e., a thione-S, comes from the neutral form of the dithiocarbazate ligand. In the LH2 ligand, an intramolecular hydroxy-O-H⋯N(imine) hydrogen bond is found. There is also an intra-ligand, charge assisted amine-N-H⋯O(phenoxide) hydrogen bond. A notable feature of the molecular packing is the formation of supramolecular chains sustained by π…π stacking interactions whereby the interacting rings are the five- and six-membered chelate and methoxybenzene rings. The chains are connected into a three-dimensional architecture by methyl-C-H⋯O(methoxy), methoxy-C-H⋯S(ester), and tolyl-C-H⋯π(tolyl) interactions.

Highlights

S-Alkyl dithiocarbazates comprise an important member of the Schiff base class of compound
S-Alkyl dithiocarbazates are generally formed by the condensation reaction of aldehydes or ketones with dithiocarbazate derivatives [3]
The presence of the mixed hard-soft nitrogen-suylfur donor atoms makes them multifaceted ligands capable of coordinating a metal ion through these, as well as additional donor atoms, when present [4,5,6]. These Schiff bases can be modified by incorporating various types of substituents to moderate/enhance their biological and pharmacological activities [7,8,9]

Summary

Introduction

S-Alkyl dithiocarbazates comprise an important member of the Schiff base class of compound They are potential sulfur-nitrogen donor ligands for metals and have been investigated since 1971 [1,2]. The presence of the mixed hard-soft nitrogen-suylfur donor atoms makes them multifaceted ligands capable of coordinating a metal ion through these, as well as additional donor atoms, when present [4,5,6] These Schiff bases can be modified by incorporating various types of substituents to moderate/enhance their biological and pharmacological activities [7,8,9]. In view of ongoing interest in the interest in the structures and biological activities of this class of Schiff base and their coordination structures and biological activities of this class of Schiff base and their coordination complexes, the complexes, the synthesis,characterization, spectroscopic characterization, and structure.

Results

This result is consistent coordination via the azomethine

General Information

Synthesis and Characterization of 1

Crystallography