Synthesis, Characterisation and Transition Metal Ion Complexation Studies of “Pocket-Like” Imine and Amide Derivatives

New families of [1+2] and [1+3] acyclic Schiff-base (imine) ligands using both di- or tri-aldehyde compounds and a variety of primary amines as precursors were prepared and fully characterised. These acyclic ligands have several extra functional groups attached, such as an OH or pyridine or imidazole rings. The imine ligands were prepared by using anhydrous magnesium sulphate and DCM/CHCl3 solution in order to prevent potential hydrolysis from occurring. Four imine ligands, due to the presence of four different primary amines (2-, 3- or 4-aminomethylpyridine and 3-aminopropylimidazole (APIM)), were formed from the various aldehydes in each of the sections in this thesis. The aldehydes chosen for this study included 4-tert-2,6-benzenedicarboxyaldehyde, 2,5-diformyl-1,4-dihydroxybenzene, 5,5'-methylene-bis-salicylaldehyde and 2,4,6-triformylphloroglucinol as well as pyridine-2,6-dicarboxaldhyde. These ligands were reacted with various MX2 salts (M = Cu, Ni, Zn, Co and Hg, and X = chloride, acetate and perchlorate). The metal complexation reactions were carried out in MeOH solution with stirring for about 2 hours. In the case of most complexation reactions, highly coloured precipitates were formed immediately. All ligands were characterised by a combination of NMR spectroscopy, IR spectroscopy and either mass spectrometry or elemental analyses. The metal complexes were analysed by NMR spectroscopy (where appropriate), IR spectroscopy, magnetic moments and elemental analyses. Despite all our efforts, no crystals, suitable for an X-ray crystallographic study, were obtained. In several cases, the formation of polymeric materials was obtained which made the determination of structures of those complexes difficult.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral

Grantor dc:publisher.institution

National University of Ireland Maynooth

Year dc:date.issued

2013

Author dc:creator

• Gao, Haixin

Language dc:language

en