Studies on metal complexes of ortho-quinone mono-oximes. Part 6. Redox behaviour of bis(4-chloro-1,2-benzoquinone 2-oximato)-copper(II) and -nickel(II); synthesis and characterization of reduced species containing a paramagnetic ligand

Bis chelated complexes of CuII and NiII with 4-chloro-1,2-benzoquinone 2-oximate, [M(cbqo)2], have been reduced either electrochemically or chemically. The new species K[M(cbqo)(cbsqo)](cbsqo = 4-chloro-1,2-benzosemiquinone 2-oximate), which contain a paramagnetic ligand, have been isolated and characterized. The mechanism of the chemical reduction, carried out by NCO––methanol, is discussed.