Functionalised azetidines as ligands: species derived by selective alkylation at substituent-nitrogen.

摘要: Selective functionalisation of the tridentate ligand 1-(2-aminoethyl)-3-methyl-3-(2-pyridyl)azetidine at its terminal amino-nitrogen atom can be readily achieved by both reductive alkylation and simple reactions to give tri-, quadri-, quinque- sexi-dentate derivatives. Simple 2-picolinyl chloride provides only example a second reaction pathway where azetidine ring reactant has undergone activation towards opening. Structural characterisation Cu(II) complexes these ligands revealed several remarkable aspects their solid-state coordination chemistry, including formation infinite helical aggregates through π-stacking tetramerisation carboxylate bridging, as well further examples crystallisation mixed species found rather common with parent ligand.