Tetrakis(selenodiazole)porphyrazines 1: Tetrakis(selenodiazole)porphyrazine and its <font>Mg</font>(<font>II</font>) and <font>Cu</font>(<font>II</font>) Derivatives. Evidence for their Conversion to Tetrakis(pyrazino)porphyrazines through Octaaminoporphyrazines

The new phthalocyanine-like macrocycle tetrakis(selenodiazole)porphyrazine, TSeDPzH 2 , and its Mg ( II ) and Cu ( II ) complexes have been prepared and their general, spectroscopic (IR, UV-vis), and magnetic properties investigated. It has been observed that the peripheral selenodiazole rings of the TSeDPz skeleton can be opened by the action of H 2 S , with release of the Se atoms and formation of a new macrocycle, i.e. octaaminoporphyrazine, which is easily converted into tetrakis(pyrazino)porphyrazine derivatives.