Digold(I) Thianthrenyl Complexes. Effect of Diphosphine Ligands on Molecular Structures in the Solid State and in Solution

Abstract

A series of digold complexes possessing two thianthrenyl ligands, Au 2 (Thi) 2 (Ph 2 P(CH 2 ) n PPh 2 ) (Thi: 1-thianthrenyl; 1 : n = 1, 2 : n = 2, 3 : n = 3, 4 : n = 4), were prepared and characterized by crystallographic and spectroscopic measurements. X-ray crystallography of complexes 1 and 3 revealed U-shaped structures with short Au–Au distances [3.2171(3) Å and 3.0735(2) Å]. Complex 2 and three of the four structure-determined molecules of complex 4 showed structures without Au–Au contacts. UV–vis spectroscopic measurements of 1 – 4 and TD-DFT calculations of the two conformers of 1 revealed that complexes 1 and 3 in the solution phase contained conformers with Au(I)–Au(I) interactions in a much higher proportion than complexes 2 and 4 . As a result, complexes with diphosphine ligands containing an odd number of methylene groups preferred structures with Au–Au interactions in the solid state and in solution. Oxidation of 1 with 2 equiv of PhICl 2 yielded a mixture of monomeric and dimeric thianthrenes and its dimer via ligand elimination and C–C coupling, respectively.

5‐Nitrofuryl‐Containing Thiosemicarbazone Gold(I) Compounds: Synthesis, Stability Studies, and Anticancer Activity

“…These absorption bands can be assigned to charge transfer (LMCT) from the thiosemicarbazones to the Au(I) center. [63,64] The band around 500 nm (t = 0) seems to indicate the presence of aurophilic interactions (Au•••Au) in solution [65][66][67] (facilitated by the increased lability of chloro ligand in DMSO). This band disappears over time, most plausibly due to formation of more stable species in solution.…”

1,8‐Diarylnaphthalenes: Synthesis, Properties, and Applications

“…[102] Naphthalene derivative 173 with two thianthrenyl groups at positions 1 and 8 was obtained in good yield by the Suzuki coupling of thianthren-1-ylboronic acid with peri-dibromide 23 (Scheme 53). [103] Self-assembling "molecular wires" are attracting the attention of scientists because they can bypass sometimes exorbitant synthetic efforts, which is important from the point of view of technological applications such as molecular electronics or solar energy conversion. Simple multinuclear ligand frameworks capable of enhancing discrete metal-to-metal interactions and propagating these (or other) interactions to multiple metal centers through non-covalent self-assembly are tempting candidates for this prospect.…”

“…Naphthalene derivative 173 with two thianthrenyl groups at positions 1 and 8 was obtained in good yield by the Suzuki coupling of thianthren‐1‐ylboronic acid with peri ‐dibromide 23 (Scheme 53). [103] …”

Stepwise Polymetalation around an sp3 Benzyl Carbon Atom

“…Such Au−Au interactions promote the metal parentage in the frontier orbitals, thus leading to higher molar absorption coefficients of metal-involved transitions. 31 Subsequently, the peak at m/z 1542.2310 corresponding to the μ 3 -[ArCM 3 ] intermediate species was identified by ESI mass spectrometry. Similarly, the 2-to-5 transformation via 2 and AuPPh 3 F also demonstrates a good fit with a pseudo-first-order equation (Figures 2a and S13a,b).…”

“…Notably, the remarkable increase of absorbance at 350 nm in the UV–vis monitoring on the 3 -to- 4 -to- 5 transformation should be ascribed to the presence of 5-fold Au–Au interactions in 5 . Such Au–Au interactions promote the metal parentage in the frontier orbitals, thus leading to higher molar absorption coefficients of metal-involved transitions . Subsequently, the peak at m / z 1542.2310 corresponding to the μ 3 -[ArCM 3 ] intermediate species was identified by ESI mass spectrometry.…”