The Complex Coordination Landscape of a Digold(I) U‐Shaped Metalloligand

Abstract

A U‐shaped di‐gold metallotweezer with two pyrene‐imidazolylidene edges and a xanthenyl‐bis‐alkynyl connector was prepared. This metallotweezer acts as metalloligand in the presence of Cu+, Tl+, or Ag+, showing three clearly distinct coordination patterns depending on the cation used. The coordination to Cu+ leads to a complex in which the metalloligand is coordinated in a pincer form. The reaction with Tl+ affords a complex in which the ligand is acting as a ϰ2‐(trans)‐chelate ligand. The reaction with Ag+ leads to a self‐assembled structure, with two silver cations encased inside the cavity of a duplex structure formed by two self‐assembled metallotweezers.

A Matter of Fidelity: Self‐Sorting Behavior of Di‐Gold Metallotweezers

“…The results that we observed are summarized in Scheme . The addition of [Cu(CH 3 CN) 4 ]BF 4 or TlPF 6 invariably generated the formation of the self‐aggregated complexes 4 and 5 , which could be obtained quasi‐quantitatively, and were unambiguously identified according to our previously published data . These species consist of the encapsulation of the metal cations (Cu + or Tl + ), in the cavity formed by the self‐aggregated structure of 2 ( 4 can be seen as Tl + @ 2 2 , and 5 as Cu + @ 2 2 ).…”

The New Di-Gold Metallotweezer Based on an Alkynylpyridine System

“…In particular, we observed that the tweezer with the anthracenyl spacer A had a great tendency to dimerize forming non-covalently bound self-aggregated duplex complexes [9,10,12]. In contrast, the complex connected with the xanthenyl spacer B served as a metalloligand for metals such as Cu + , Ag + , and Tl + [11]. The complex with the carbazolyl spacer C was able to encapsulate planar aromatic guests by approaching its two polyaromatic arms, and thus showed an interesting example of a guest-induced-fit conformational arrangement [13,14].…”

“…During the last few years, we reported a series of metallotweezers based on the use of two pyrene-bis-imidazolylidene-gold(I) arms bound with four different bis-alkynyl spacers (Scheme 1) [9][10][11][12][13][14][15]. These tweezers benefit from the tendency of Au(I) complexes to show linear geometry, and from the ability of the pyrene moieties to establish π-π-stacking interactions.…”

Shape‐Adaptability and Redox‐Switching Properties of a Di‐Gold Metallotweezer

“…In particular, the anthracenyl‐linked complex 1 showed a great tendency to self‐aggregate in non‐polar solvents and in the presence of cations such as Cu + , Ag + and Tl + [9] . The xanthenyl‐linked complex 2 showed interesting coordinating abilities that were highly dependent on the type of metal used [9b,10] . Finally, the carbazolyl‐linked complex 3 , was able to encapsulate planar polycyclic aromatic hydrocarbons (PAHs), displaying larger associating constants for those planar guests functionalized with groups able to hydrogen bond with the NH group of the carbazolyl spacer [11] .…”

“…[9] The xanthenyl‐linked complex 2 showed interesting coordinating abilities that were highly dependent on the type of metal used. [ 9b , 10 ] Finally, the carbazolyl‐linked complex 3 , was able to encapsulate planar polycyclic aromatic hydrocarbons (PAHs), displaying larger associating constants for those planar guests functionalized with groups able to hydrogen bond with the NH group of the carbazolyl spacer. [11] Noteworthy, all our host‐guest chemistry studies with 3 were performed using electron‐donor planar guests, thus the association constants that we found were rather low.…”