Reactions of cobaltadithiolene complexes with aryl azides: Formations of metal chelate rings containing nitrogen atoms by substitution reactions via nitrene

In the reactions of cobaltadithiolene complexes [CpCo(S2C2Z2)] (Z=CN, COOMe, Ph, Me) with aryl azides, two types of substitution reactions occurred. One is the replacements of the sulfur of cobaltadithiolene by arylimido groups and the other is the replacements of the SCZCZ moiety of cobaltadithiolene. The product of latter reaction was also formed by the reactions of the metal cluster complex [Cp4Co4S6] with aryl azides. The azides with electron-donating substituents gave these products in higher yields than those with electron-withdrawing substituents. In these reactions, arylnitrenes as intermediates were predictable. The reactions of [CpCo(dmit)] (dmit=C3S5) with phenyl azide and tosyl azide led to the replacements of the terminal sulfur (CS) of the dmit ligand by imido groups to give novel imine complexes [CpCo(S2C2S2CNR)] (R=Ph, Ts).