Patent ID: 6555681
Filing Date: 2003-04-29
Classification: C07D

Abstract:
A process for preparing a tetraaza macrocyclic ligand having the formula: wherein each R is independently C1-C22 linear alkyl, C1-C22 branched alkyl, C7-C22 alkylenearyl, C8-C22 alkyl substituted alkylenearyl, and mixtures thereof; each index n is independently from 0 to 3, said process comprising the steps of:a) reacting one mole equivalent of a tetraaza macrocyclic ligand precursor having the formula: â€ƒwherein Xâˆ’ is an anion which provides charge neutrality, with from 1 mole equivalent to 3 mole equivalents a reducing agent having the formula MBH4 wherein M is selected from the group consisting of lithium, sodium, potassium, and mixtures thereof; at a pH of at least 11 to form a macrocyclic ligand; and b) optionally isolating said macrocyclic ligand.