Table 2.

Unsymmetrical tetradentate Schiff base ligands and their Cu(II) and Fe(III) complexes.

R1	R2	R3	Ligand	Cu(II) complex	Fe(III) complex
t-Bu	H	H	H2L1	[Cu(II)L1]	[Fe(III)L1Cl]
t-Bu	F	H	H2L2	[Cu(II)L2]	[Fe(III)L2Cl]
t-Bu	Cl	H	H2L3	[Cu(II)L3]	[Fe(III)L3Cl]
t-Bu	Br	H	H2L4	[Cu(II)L4]	[Fe(III)L4Cl]
OCH3	H	OCH3	H2L5	[Cu(II)L5]	[Fe(III)L5Cl]