Designer ligands. Part 3. Synthesis of pgm-specific bidentate and tridentate ligands

Designer ligands: The search for metal ion selectivity

“…(iii) additional sulphur donors for multidentate coordination with the metal centre; (iv) S-and N-donor atoms for metal chelation; and (v) substituents (R 1 and R 3 ) to fine-tune N-donor capacity. 22,23 The preparation of polydentate ligands incorporating these features is outlined in Schemes 2 and 3. 22,23 Thus, the bidentate and tridentate ligands 12 and 13 were obtained from the anilines 11 via the corresponding benzothiazole intermediates, while access to the tetradentate ligands 16 was achieved by the use of disulphide linkages as a protection strategy.…”

“…para to the amide function to fine-tune electron density on amide nitrogen Sources: Hagemann and Kaye22,23 …”

Designer ligands: The search for metal ion selectivity

“…22,23 The preparation of polydentate ligands incorporating these features is outlined in Schemes 2 and 3. 22,23 Thus, the bidentate and tridentate ligands 12 and 13 were obtained from the anilines 11 via the corresponding benzothiazole intermediates, while access to the tetradentate ligands 16 was achieved by the use of disulphide linkages as a protection strategy. The structure and size distribution of the polymeric intermediates represented by structure 15 were not material factors, as reductive cleavage of all the disulphide links afforded the desired tetradentate ligands 16 as the sole monomeric unit in each case.…”

Designer Ligands. Part 10.1 Novel Nickel(Ii)-Selective Ligands for Use in the Construction of Molecularly Imprinted Polymers

“…

Our research on metal-selective ligands has previously been focused on the development of systems capable of chelating copper, 2 silver 3 and platinum group metals. 4 In this communication, we discuss the design, synthesis and evaluation of novel bidentate ligands for use in the construction of nickel(II)-selective molecularly imprinted polymers (MIPs).Various ligands, which contain nitrogen donors (especially pyridyl) and which are capable of forming five-membered chelates, are known to form stable, four-coordinate nickel(II) complexes. 5 These factors were consequently considered in designing potential nickel(II)-selective ligands, the structural features of which are illustrated in Fig.

…”

“…Our research on metal-selective ligands has previously been focused on the development of systems capable of chelating copper, 2 silver 3 and platinum group metals. 4 In this communication, we discuss the design, synthesis and evaluation of novel bidentate ligands for use in the construction of nickel(II)-selective molecularly imprinted polymers (MIPs).…”