Diverse binding of cationic guests by highly substituted [3 + 3] Schiff-base macrocycles

Schiff-base macrocycles interact with ammonium-based guests to form threaded pseudorotaxanes or unthreaded external complexes, and tautomerize in the process.

Three Manganese Complexes of Anionic N4-Donor Schiff-Base Macrocycles: Monomeric MnII and MnIII, and dimeric MnIV

Three manganese macrocyclic complexes of two anionic N4-donor [1+1] Schiff-base macrocycles that differ in ring size (14 versus 16 membered), HLEt and HLPr (obtained from condensation of diphenylamine-2,2′-dicarboxaldehyde and either diethylenetriamine or dipropylenetriamine), are reported. Specifically, a pair of monomeric complexes MnIILEt(NCS)(H2O) and [MnIIILPr(NCS)2]·0.5H2O, plus a dimeric complex [MnIV2LEt2(O)2](ClO4)2·3DMF have been synthesised and characterised. Single crystal structure determinations on [MnIIILPr(NCS)2]·0.5H2O and [MnIV2LEt2(O)2](ClO4)2·3DMF revealed octahedral manganese centres in both cases: N6-coordinated Jahn–Teller distorted MnIII in the former and a pair of N4O2-coordinated MnIV in the latter. UV-Vis, IR, and electron paramagnetic resonance spectroscopy as well as magnetic measurements are reported. These macrocyclic complexes feature a simple and original design, and could find future uses as models for manganese catalase or as building blocks for the assembly of larger supramolecular architectures.

Carbazole-based N4-donor Schiff base macrocycles: obtained metal free and as Cu(ii) and Ni(ii) complexes

Practical multi-step routes to 1,8-diformylcarbazole head units, and the first examples of Schiff base macrocycles derived from them, are reported. Like porphyrins, both macrocycles are shown to impose a strong ligand field.