A large number of complexes of tetraaza macrocyclic ligands is known. These ligands have from 12 to 16 atoms in the ring, and the most common structure is a 14-membered ring. The simplest of the ligands is 1,4,8,1 l-tetraazacyclotetradecane :A variety of metal complexes of this ligand have been prepared, including the metals C O ,~ Ni,2 and Rh.3 Coordination is generally in a planar fashion, although cis coordination to CO(III)~ has been reported. These complexes were first prepared by direct interaction of the ligand with the metal salt. Unfortunately, this ligand, unlike others of its class,5 has previously been available only through laborious organic syntheses.V Recently an in situ preparation of the nickel(I1) complex was reported.7 The ligand can easily be removed from the nickel(I1) and used in the preparation of other metal complexes.Given here is an improved version of this in situ synthesis which provides high yields of the nickel(I1) perchlorate complex. Procedures for removing the ligand from the metal and for its purification are also given.

A pseudophase diagram for ternary compositions of n-hexane, water and 2-propanol has been published previously. Some of the compositions exhibited the physical characteristics of a water/oil (w/o) microemulsion even though a detergent was not present. We have now determined the effect of ionic materials on the system by replacing water with NaCI solutions'. Addition of NaCI caused significant changes in the location of region boundaries. The microemulsion was stabilized while a region of small H-bonded aggregates appeared to be destabilized by the added NaCI. An investigation of these systems by NMR, with or without added NaCI, showed that "bulk" water was present in the detergentless microemulsion. In addition, NMR was found to be a useful tool for locating region boundaries and for elucidating the nature of compositions assigned to these regions.

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