Lead II Complexes

13 COMPLEX COMPOUNDS OF LEAD 5.13.1 Lead(II) complexes (J.Chem Educ. 74(1997)291) 

The first complex formed when KI solution is added to the sparingly soluble yellow Pbl2, is the white KPblj. 

To a small crystal of Kl add a drop of 0.1 M lead nitrate solution and note its appearance, preferably by looking throu a low power microscope. Repeat using larger and larger crystals and compare their appearance on adding a drop of lead solution in each case. 

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Certain lead(II) complexes were shown to display reversible redox behavior on the CV scale. Examples are Pb(II) complexes of 2(o-hydroxyphenyliminomethyl)-pyrrole and 2(o-hydroxyphenyliminomethyl)-thiophene. Their stability constants were also determined by polarography140. Anodic exchange reactions of extracted metal chelates were carried out with 1-pyrrolidinecarbodithioic acid in isobutyl methyl ketone141. 

Lead(II) complexes, related 7t-complexes, 3, 893 Lead compounds... 

Town, R.M. (1998) Chronopotentiometric stripping analysis as a probe for copper(II) and lead(II) complexation by fulvic acid limitations and potentialities. Anal. Chim. Acta, 363, 31-43. 

FIGURE 93. ORTEP drawings of the lead(II) complex [PKL KBPIut) , showing the Pb atom and one of the two macrocycles. Reproduced by permission of Elsevier Science from Reference 140... 

The anionic platinum-lead(II) complex [PbjPt(CgFs jj]2 in which the Pb atom is linearly bonded to two Pt atoms was obtained in methanol (equation 190)518. 

A combination of potentiometric and absorption spectroscopic data allowed the authors to characterize the formation and the dissociation mechanism of octacoordinated lead(II) complexes of primary and tertiary tetrakiscarbamoyl-methyl cyclam derivatives. 

An example of an eight-coordinate lead(II) complex is given by [HB(l,2,4-triazolyl)3]2-Pb(H20)2. From the same reaction mixture, a polymeric material [ HB( 1,2,4-triazolyl)3 -(K -N03-0)(H20)Pb]oo was identified crystallographicalW and the geometry at the lead suggested that the metal had a stereochemically active lone paird ... 

Number of Lead(II) Complexes Found in the CSD, Grouped According to Coordination Number... 

Singh and coworkers synthesized lead(II) complexes of reduced glutathione (GSH) of general composition [Pb(L)(X)] H20 (where L=GSH X=C1, NO3, CH3COO, NCS). TG and DTA studies indicated the coordination of cysteinyl sulfiir with metal ion and the presence of water molecules in the complexes. The thermal behaviour of the complexes shows that the water molecule is removed in the first step, followed by the removal of anions and then by the decomposition of the ligand in the subsequent steps. The thermal decomposition of all the complexes proceeds via first-order kinetics [189]. 

Garcia. A.M. Romero-Salguero, J. Bassani, D.M. Lehn. J.-M. Baum. G. Fenske. D. Self-assembly and characterization of multimetallic grid-type lead(II) complexes. Chem. Eur. J. 1999. 5, 1803-1808. 

In a polarographic study, the rates of dissociation of some aminopolycarboxylato-zinc(n), -cadmium(ii), and -lead(ii) complexes have been measured, and n.m,r. has been used in an analogous study on the same metals. The kinetics of the dissociation of the cobalt(ii) complex of ethylenediamine monoacetate have also been measured polarographically, and the rate constants for the formation of the cobalt(n) complexes of anthranilate, salicylate, 5-sulphosalicylate, and ligand (5) have been compared with those of the respective nickel(n) analogues. 

PbSe NCs were also synthesised from the bis[iV,A-diisobutyl-A -(4-nitrobenzoyl)selenoureato]lead(II) complex by colloidal method. The precursor dissolved in a mixture of TOP and ODE was rapidly injected into a flask containing a mixture of TOP, ODE and OA heated at 200 or 250 °C. Spherical PbSe NCs of 12-14 nm diameter were obtained at 200 °C, whereas cubic PbSe NCs of 18-21 nm diameter were observed... 

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