Thiosemicarbazones as co-ordinating agents. Part 2. Synthesis, spectroscopic characterization, and X-ray structure of aquachloro(pyridoxal thiosemicarbazone)manganese(II) chloride and aqua(pyridoxal thiosemicarbazonato)-copper(II) chloride monohydrate

Publisher Website
Google Scholar
Abstract
The chelating behaviour of neutral (H2L) and deprotonated pyridoxal thiosemicarbazone has been investigated in two new complexes, [Mn(H2L)(OH2)Cl]Cl (1) and [Cu(HL)(OH2)]Cl·H2O (2). Both crystal structures have been determined using single-crystal X-ray diffraction methods. Compound (1) crystallizes in space group P21/n, with a= 13.902(4), b= 9.316(1), c= 11.982(3)Å, β= 107.61(2)° and Z= 4; compound (2) crystallizes in space group P, with a= 9.732(2), b= 9.491(3), c= 7.894(2)Å, α= 95.73(3), β= 101.65(3), γ= 79.30(2)°, and Z= 2. The structures were solved by the heavy-atom method and refined to R values of 0.057 and 0.044 respectively. The co-ordination geometry about the manganese(II) ion, in the monomer (1), is based on an uncommon distorted square pyramid, with H2L together with the H2O molecule forming the equatorial plane and the Cl atom occupying the axial position. The CuII ion, in compound (2), has a square-planar geometry with phenolic oxygen, imine nitrogen, sulphur, and a water molecule as the basal donors. A sulphur atom of a centrosymmetrically related molecule, occupying the axial position, serves as a bridging element to form a dimeric structure. Both compounds are paramagnetic and their effective magnetic moments are 4.37 for (1) and 1.81 for (2). The main vibrational bands are also reported and discussed.