Reactions of octacyanomolybdate(V) and octacyanotungstate(V) with s(2) metal-ion reducing centers.

The s(2) centers, Sn(II), Ge(II), and In(i) reduce Mo(V)(CN)(8)(3-) and W(V)(CN)(8)(3-) quantitatively to the corresponding octacyanomolybdate(IV) and -tungstate(iv) anions. Reductions by In(i) proceed 10(3)-10(5) times as rapidly as those by Sn(II) and Ge(II). All reactions are triggered by a single electron oxidation, yielding a much more reactive s(1) intermediate. Reductions by Sn(II) in chloride medium proceed predominantly through the SnCl(3)(-) anion. The Ge(II)-W(CN)(8)(3-) reaction is initiated by a slow unimolecular heterolysis of the Ge(II) center, yielding very nearly linear profiles when the reductant is in excess.