Aminotriazines as Locking Fragments in Macrocyclic Synthesis

Abstract

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.

Interactions between Copper(II) Complexes of Mono-, Bis-, and Tris(macrocyclic) Ligands and Inorganic or Organic Guests

“…In the published structures (9 and 11), specific supramolecular interactions of the melamine fragments with substrates (carboxylates) were discussed. [16,17] The structural parameters of all complexes are very similar; the main variations are in the axial coordination and the angles α, β, and γ. The structures reported here are sixcoordinate, with ClO 4…”

“…They include the mono(macrocyclic) ligand complexes [Cu(L 1 )(OClO 3 [17] [Cu(L 1 )(CA-H)-(OClO 3 )]·H 2 O (9) (CA-H ϭ cyanurate), [17] [Cu(HL 1 )-(OClO 3 )](ClO 4 ) 2 ·2H 2 O (10), [16] [Cu(HL 1 )(OClO 3 ) 2 ]-(BA-H)·3H 2 O (11) (BA-H ϭ barbiturate), [17] and [Cu 3 (L 3 )(OH 2 ) 2 (OClO 3 ) 4 ](ClO 4 ) 2 ·3H 2 O (12). [18] The copper(II) ions in all structures reported here are coordinated to four nitrogen donors in the macrocycles, resulting in nearly planar CuN 4 chromophores (rms ϭ 0.01Ϫ0.04 Å ), with the copper(II) centers deviating from these planes only slightly (0.01Ϫ0.07 Å ).…”

“…Three new structures of copper(II) complexes of L 1 are reported here (for ORTEP plots [33] see Figure 2), while four have been published before; [16,17] structural parameters for these are also included in Table 1. In three of the structures (1, 8, and 9), copper(II) is coordinated to the parent ligand L 1 , while in the other four (2, 3, 10, and 11) the melamine fragment is protonated at the central nitrogen atom ([N (8) and N (18) in Figure 2b,c), and so copper(II) is coordinated to HL 1 .…”

Metallacycles or coexistence of isomeric metallacycle and chain: Anion-dependent luminescent Ag complexes of a flexible diaminotriazine–imidazole ligand

“…Furthermore, the excellent H-bonding ability of diaminotriazinyl (DAT) group has been successfully used in combination with coordination bonds in some DAT based rigid ligands for crystal engineering [24][25][26][27][28]. However, there are still no reports of flexible ligands incorporating the DAT group, and in this work, we selected a flexible ligand 2,4-diamino-6-[2-(2-methyl-1-imidazolyl) ethyl]-1,3,5-triazine (L) based on the following reasons.…”

Self-Assembly of Three-Dimensional Copper(II) Macrocyclic Complex with 2,5-Pyridinedicarboxylate Linked by Hydrogen Bond

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] Hydrogen bonds play vital roles in highly efficient and specific biological reactions and are essential for molecular recognition and self-organization of molecules in supramolecular chemistry. The coordination environment of the metal is generally constrained by the macrocyclic ligand, so the metal may be considered to be an inert substituent on the hydrogen bonding organic fragment.…”