Tri‐ and Tetranuclear Metal‐String Complexes with Metallophilic d10–d10 Interactions. Issue 1 (26th November 2019)

• Record Type: Journal Article
• Authors: Olaru, Marian; Kögel, Julius F.; Aoki, Risa; Sakamoto, Ryota; Nishihara, Hiroshi; Lork, Enno; Mebs, Stefan; Vogt, Matthias; Beckmann, Jens
• Is Part Of: Chemistry. Volume 26:Issue 1(2019)
• Page Start: 275
• Page End: 284
• Publication Date: 2019-11-26
• Subjects: gold -- ligand design -- mercury -- metallophilic interactions -- metallopincer; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201904106
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: The reaction of 2, 6‐F2 C6 H3 SiMe3 with Ph2 PLi provided 2, 6‐(Ph2 P)2 C6 H3 SiMe3 (1 ), which can be regarded as precursor for the novel anionic tridentate ligand [2, 6‐(Ph2 P)2 C6 H3 ] − ( PCP ) − . The reaction of 1 with [AuCl(tht)] (tht=tetrahydrothiophene) afforded 2, 6‐(Ph2 PAuCl)2 C6 H3 SiMe3 (2 ). The subsequent reaction of 2 with CsF proceeded with elimination of Me3 SiF and yielded the neutral tetranuclear complex linear ‐[Au4 Cl2 ( PCP )2 ] (3 ) comprising a string‐like arrangement of four Au atoms. Upon chloride abstraction from 3 with NaBAr F 4 (Ar F =3, 5‐(CF3 )2 C6 H3 ) in the presence of tht, the formation of the dicationic tetranuclear complex linear ‐[Au4 ( PCP )2 (tht)2 ](BAr F 4 )2 (4 ) was observed, in which the string‐like structural motif is retained. Irradiation of 4 with UV light triggered a facile rearrangement in solution giving rise to the dicationic tetranuclear complex cyclo ‐[Au4 ( PCP )2 (tht)2 ](BAr F 4 ) (5 ), which comprises a rhomboidal motif of four Au atoms. In 3 –5, the Au atoms are associated by a number of significant aurophilic interactions. The atom‐economic and selective reaction of 3 with HgCl2 yielded the neutral trinuclear bimetallic complex [HgAu2 Cl3 ( PCP )] (6 ) comprising significant metallophilic interactions between the Au and Hg atoms. Therefore, 6 may be also regarded as a metallopincer complex [ClHg( AuCAu )] between Hg II and the anionic tridentate ligand [2, 6‐(Ph2 PAuCl)2 C6 H3 ] − ( AuCAu ) − containing a central carbanionic binding site and two "gold‐arms" contributing pincer‐type chelation trough metallophilic interactions. Compounds 1 –6 were characterized experimentally by multinuclear NMR spectroscopy and X‐ray crystallography and computationally using a set of real‐space bond indicators (RSBIs) derived from electron density (ED) methods including Atoms In Molecules (AIM), the Electron Localizability Indicator (ELI‐D) as well as the Non‐Covalent Interaction (NCI) Index. Abstract : Heavy metal interactions : The synthesis and characterization of several tetranuclear gold complexes and of a trinuclear bimetallic (metallopincer) complex featuring metallophilic interactions is described in this work.