Long-lived homogenous amide containing macrocyclic compounds

A compound comprising:

• a macrocyclic tetradentate ligand of the structure ##STR597## wherein:
• D is a donor atom selected from the group consisting of N and O;
• each X is a position for addition of a substituent and, when D is N, each position is (i) not occupied such that a double bond is formed between D and an atom adjacent to D, or (ii) is selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, aryl, alkoxy, phenoxy, halogen, halogenated alkyl, halogenated aryl, halogenated alkenyl, halogenated alkynyl, perhaloalkyl, perhaloaryl, a substituted or unsubstituted cycloalkyl ring, a substituted or unsubstituted cycloalkenyl ring, a substituted or unsubstituted saturated heterocyclic ring, a substituted or unsubstituted unsaturated heterocyclic ring, and at least one X is hydrogen, and when D is O, the position is not occupied;
• Y.sub.1, Y.sub.2, Y.sub.3 and Y.sub.4 are the same or different and each is a unit selected from the group consisting of ##STR598## wherein:
• Q is oxygen or ZR'
• Z is selected from the group consisting of N, P and As;
• and,
• R' is selected from the group consisting of hydrogen, alkyl, alkenyl, alkynyl, aryl, alkoxy, phenoxy, halogen, halogenated alkyl, halogenated aryl, halogenated alkenyl, halogenated alkynyl, perhaloalkyl, perhaloaryl, a substituted or unsubstituted cycloalkyl ring, a substituted or unsubstituted cycloalkenyl ring, a substituted or unsubstituted saturated heterocyclic ring, a substituted or unsubstituted unsaturated heterocyclic ring;
• R.sub.5, R.sub.6, R.sub.7 and R.sub.8, pairwise and cumulatively, are the same or different and each (i) is selected from the group consisting of alkyl, aryl, halogen, jalogenated alkyls, perhaloalkyl, halogenated aryls, perhaloaryl, CF.sub.3, CH.sub.2 CF.sub.3, cycloalkyl, cycloalkenyl, alkynyl, alkylaryl, alkoxy, phenoxy, oxylic, phenyl, or (ii) together with an R substituent on an adjacent carbon in the same Y unit, form a mono-, di-, tri- or tetra- substituted or unsubstituted benzene ring of which two carbons in the ring are adjacent carbons in the same Y unit, or (iii) together with a paired R bound to the same carbon atom form a substituted or unsubstituted cycloalkyl or substituted or unsubstituted cycloalkenyl ring;
• R.sub.1 and R.sub.2 are the same or different, linked or nonlinked, and each is selected from the group consisting of substituents which are unreactive, form strong bond intramolecularly with said R, and R.sub.2 and with the carbon of the Y unit to which each is bound, are sterically hindered and are conformationally hindered such that oxidative degradation of a metal complex of the compound is restricted when the complex is in the presence of an oxidizing agent, or together with an R substituent on an adjacent carbon in the same Y unit, form a mono-, di-, tri- or tetra- substituted or unsubstituted benzene ring of which two carbons in the ring are adjacent carbons in the same Y unit.