Synthesis of Gold(III) Complexes with Bidentate Amino-Thiolate Ligands as Precursors of Novel Bifunctional Acyclic Diaminocarbenes

Two neutral bis­(pentafluorophenyl)­thiolate gold­(III) complexes
with the unsymmetrical S^N ligands 2-aminothiophenol or cysteamine
have been synthesized and their reactivity has been studied. Homo-
and heterodinuclear compounds were obtained by their coordination
to gold­(I) or silver­(I) derivatives through the sulfur atom. Interestingly,
a tetranuclear derivative bearing short gold­(I)···gold­(I)
and the more unusual gold­(I)···gold­(III) interactions
has been prepared. These amino-thiolate derivatives can be used as
precursors for the synthesis of novel gold­(III) acyclic diaminocarbene
complexes by reaction with isocyanides CNR. The nucleophilic attack
of the amino group to isocyanide molecules affords the synthesis of
unprecedented bidentate C^S acyclic diaminocarbene ligands. All of
the complexes are air- and moisture-stable at room temperature and
have been spectroscopically and structurally characterized.