The dinucleating macrocyclic ligands (L
2;2)
2- and (L
2;3)
2-, comprised of two 2-[(
N-methylamino)methyl]-6-(iminomethyl)-4-bromophenolate entities combined by the -(CH
2)
2- chain between the two aminic nitrogen atoms and by the-(CH
2)
2- or -(CH
2)
3- chain between the two iminic nitrogen atoms, have afforded the following M
IICu
II complexes:[CoCu(L
2;2)](ClO
4)
2·MeCN (
1A), [NiCu(L
2;2)](ClO
4)
2 (
2A), [ZnCu(L
2;2)](ClO
4)
2·0.5MeCN·EtOH (
3A), [CoCu(L
2;3)(MeCN)(2-PrOH)](ClO
4)
2 (
4A), [NiCu(L
2;3)](ClO
4)
2 (
5A), and [ZnCu(L
2;3)](ClO
4)
2·1.5DMF (
6A). [CoCu(L
2;2)(MeCN)
3](ClO
4)
2(
1A') crystallizes in the monoclinic space group
P2
1/
n,
a = 11.691(2) Å,
b = 18.572(3) Å,
c = 17.058(3) Å,
![](/images/gifchars/beta2.gif)
=91.18(2)
![](/images/entities/deg.gif)
,
V = 3703(1) Å
3, and
Z = 4. [NiCu(L
2;2)(DMF)
2](ClO
4)
2 (
2A') crystallizes in the triclinic space group
P![](/images/entities/onemacr.gif)
,
a = 11.260(2) Å,
b = 16.359(6) Å,
c = 10.853(4) Å,
![](/images/gifchars/alpha.gif)
= 96.98(3)
![](/images/entities/deg.gif)
,
![](/images/gifchars/beta2.gif)
= 91.18(2)
![](/images/entities/deg.gif)
,
![](/images/gifchars/gamma.gif)
= 75.20(2)
![](/images/entities/deg.gif)
,
V = 1917(1)Å
3, and
Z = 2.
4A crystallizes in the monoclinic space group
P2
1/
c,
a = 15.064(8) Å,
b = 11.434(5) Å,
c =21.352(5) Å,
![](/images/gifchars/beta2.gif)
= 95.83(2)
![](/images/entities/deg.gif)
,
V = 3659(2) Å
3, and
Z = 4. The X-ray crystallographic results demonstrate the M
IIto reside in the N(amine)
2O
2 site and the Cu
II in the N(imine)
2O
2 site. The complexes
1-6 are regarded to beisomeric with [CuCo(L
2;2))](ClO
4)
2·DMF (
1B), [CuNi(L
2;2))](ClO
4)
2·DMF·MeOH (
2B), [CuZn(L
2;2))](ClO
4)
2·H
2O (
3B)),[CuCo(L
2;3))](ClO
4)
2·2H
2O (
4B), [CuNi(L
2;3))](ClO
4)
2 (
5B), and [CuZn(L
2;3))](ClO
4)
2·H
2O (
6B) reported previously,when we ignore exogenous donating and solvating molecules. The isomeric M
IICu
II and Cu
IIM
II complexes aredifferentiated by X-ray structural, magnetic, visible spectroscopic, and electrochemical studies. The two isomericforms are significantly stabilized by the "macrocyclic effect" of the ligands, but
1A is converted into
1B on anelectrode, and
2A is converted into
2B at elevated temperature.