Reactions of metal dithizonates with porphyrins

Reactions of monosubstituted dithizonates MDz(2) [M = Cu(II), Co(II), Ni(II ), Cd(II), Hg(II), and Zn(II)I with N-methyltetraphenylporphin H(N-CH3)TPP in dimethyl sulfoxide are studied. It is found that Cu(II), Ni(II), and Hg( II) dithizonates do not enter this reaction. The rate of complexation betwe en H(N-CH3)TPP and Co(II), Cd(II), and Zn(II) dithizonates increases in the order of Co < Zn < Cd. The reaction mechanism and reasons for different ca pability of dithizonates for coordinating with NH-active porphyrins are sug gested.