In the search for porphyrinoids with a built-in cyclopentadienyl moiety (true carbaporphyrins), A. Berlicka has synthesized carbathiaporphyrin. The donors (C,N,S,N) in the porphyrinic core of carbathiaporphyrinoid are potentially of fundamental importance for generating organometallic complexes, as exemplified through formation of the palladium(II) complex.
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