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The synthesis of dithiocarbamate ligands based on a pyrrole framework is reported. These ligands self-assemble with zinc(), nickel() and copper() to afford neutral, dinuclear metallomacrocycles and trinuclear metallocryptands. The assembled metallo compounds have been characterised by a range of techniques, including 1 H NMR, UV-vis spectroscopy, elemental analysis, mass spectrometry and X-ray crystallography. Some preliminary anion binding studies have also been conducted, using electronic spectroscopy and electrochemistry. The nickel macrocycles showed some affinity for acetate, whereas the copper cryptand showed affinity for benzoate anions. The copper cryptand also exhibited a significant electrochemical response to a range of anions.Scheme 1 Preparation of acyclic transition metal complexes of pyrrole-based ligands.

The macrocyclic compounds (6-(4',6'-diamino-1',3',5'-triazinyl)-1,4,6,8,11-pentaazacyclotetradecane)copper(II) triperchlorate dihydrate, [Cu(HL(2))](ClO(4))(3).2H(2)O, (6-(6'-amino-4'-oxo-1'H-1',3',5'-triazinyl)-1,4,6,8,11-pentaazacyclotetradecane)copper(II) diperchlorate hydrate, [CuL(3)](ClO(4))(2).H(2)O, and [(6-(4',6'-dioxo-1'H-1',3',5'-triazinyl)-1,4,6,8,11-pentaazacyclotetradecane)copper(II)] diperchlorate, [CuL(4)](ClO(4))(2), have been synthesized. The macrocycles synthesized contain respectively pendant melamine, ammeline, and ammelide rings. The X-ray cyrstallographic analyses of [Cu(HL(2))](ClO(4))(3).2H(2)O, triclinic, space group P&onemacr;, a = 9.489(10) Å, b = 12.340(2) Å, c = 24.496(4) Å, alpha = 87.74(10) degrees, beta = 85.51(10) degrees, gamma = 70.95(10) degrees, and Z = 4, and {[CuL(3)](ClO(4))(2).H(2)O}(2), monoclinic, space group C2/c, a = 18.624(8) Å, b = 17.160(2) Å, c = 15.998(6) Å, beta = 117.82(2) degrees, and Z = 4, are reported. The structure of [Cu(HL(2))](ClO(4))(3).2H(2)O shows the formation of linear tapes, formed by a combination of hydrogen bonds and pi-pi stacking interactions. The structure of [CuL(3)](ClO(4))(2).H(2)O displays formation of dimers, formed by a coordinate bond from the oxygen in one molecule to the copper atom of another. The tautomeric forms of the ammeline and ammelide moieties have been determined. The potential of these compounds as subunits for cocrystallization has been investigated.

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