Synthesis and co-ordination chemistry of the sterically demanding pendant-arm macrocycle N,N′,N″-tris[(2R)-2-hydroxy-3-methylbutyl]-1,4,7-triazacyclononane

Abstract

The sterically demanding pendant-arm macrocycle N,N′,N″-tris[(2R)-2-hydroxy-3-methylbutyl]-1,4,7-triazacyclononane H₃L has been synthesised. Owing to its bulky isopropyl arms the formation of dimeric species is prevented which is in contrast to the behaviour of the analogous ligand with methyl substituted arms, N,N′,N″-tris[(2R)-2-hydroxypropyl]-1,4,7-triazacyclononane (H₃L′). The preparation of complexes of V^IV,Cr^III, Mn^IV Ni^II, Cu^II and Zn^II with H₃L is described and the crystal structures and some spectroscopic properties of [Mn^IVL][PF₆]·H₂O and [Ni^II(H₃L)][NO₃][PF₆] determined.