TY - JOUR

T1 - Intramolecular aurophilic interactions in dinuclear gold(i) complexes with twisted bridging 2,2′-bipyridine ligands

AU - Shmelev, Nikita Y.

AU - Okubazghi, Tesfu H.

AU - Abramov, Pavel A.

AU - Komarov, Vladislav Y.

AU - Rakhmanova, Mariana I.

AU - Novikov, Alexander S.

AU - Gushchin, Artem L.

N1 - Funding Information: Financial support from the Russian Science Foundation (grant no. 21-13-00092) is acknowledged. The authors thank the Ministry of Science and Higher Education of the Russian Federation (grants no. 121031700315-2 and 121031700313-8) for the access to the equipment of the Centre of Collective Usage of NIIC SB RAS. Publisher Copyright: © The Royal Society of Chemistry 2021.

PY - 2021/9/28

Y1 - 2021/9/28

N2 - Elimination of the chloride ion from the [(PPh3)AuCl] complex using silver triflate (AgOTf) in the presence of 2,2′-bipyridine R2bpy (the Au : R2bpy molar ratio is 2 : 1) in dichloromethane at room temperature leads to dinuclear gold(i) complexes [(PPh3Au)2(μ-R2bpy)](OTf)2(R2bpy = bpy (1), dbbpy (2), CH3Obpy (3), 3-CO2CH3bpy (4), 4-CO2CH3bpy (5)) in high yields. The crystal structures for all compounds were determined using X-ray diffraction analysis. In all structures, gold ions are in a typical linear environment, and the bipyridine molecule is twisted, which allows intramolecular aurophilic interactions. Relatively short Au(i)⋯Au(i) contacts (3.1262 (2)-3.400 (1) Å) are found in structures3-5. DFT calculations show the presence of bond critical points (3, −1) for aurophilic interactions in these structures. In structures1and2, the Au(i)⋯Au(i) distances are noticeably larger and equal to 4.479 (1) and 4.589 (1) Å respectively; there are no bond critical points (3, −1) for aurophilic interactions. All complexes show photoluminescence in solid state at room temperature when excited at 300 nm in a wide spectral range: from blue or blue-green emission (400-460 nm) for1-4to orange emission (580 mn) for5. The lifetimes of the excited state are in the microsecond range which is characteristic of phosphorescence. TD-DFT calculations reveal that electronic transitions of different nature are responsible for the photoluminescence of these compounds.

AB - Elimination of the chloride ion from the [(PPh3)AuCl] complex using silver triflate (AgOTf) in the presence of 2,2′-bipyridine R2bpy (the Au : R2bpy molar ratio is 2 : 1) in dichloromethane at room temperature leads to dinuclear gold(i) complexes [(PPh3Au)2(μ-R2bpy)](OTf)2(R2bpy = bpy (1), dbbpy (2), CH3Obpy (3), 3-CO2CH3bpy (4), 4-CO2CH3bpy (5)) in high yields. The crystal structures for all compounds were determined using X-ray diffraction analysis. In all structures, gold ions are in a typical linear environment, and the bipyridine molecule is twisted, which allows intramolecular aurophilic interactions. Relatively short Au(i)⋯Au(i) contacts (3.1262 (2)-3.400 (1) Å) are found in structures3-5. DFT calculations show the presence of bond critical points (3, −1) for aurophilic interactions in these structures. In structures1and2, the Au(i)⋯Au(i) distances are noticeably larger and equal to 4.479 (1) and 4.589 (1) Å respectively; there are no bond critical points (3, −1) for aurophilic interactions. All complexes show photoluminescence in solid state at room temperature when excited at 300 nm in a wide spectral range: from blue or blue-green emission (400-460 nm) for1-4to orange emission (580 mn) for5. The lifetimes of the excited state are in the microsecond range which is characteristic of phosphorescence. TD-DFT calculations reveal that electronic transitions of different nature are responsible for the photoluminescence of these compounds.

UR - http://www.scopus.com/inward/record.url?scp=85115655288&partnerID=8YFLogxK

U2 - 10.1039/d1dt02164h

DO - 10.1039/d1dt02164h

M3 - Article

C2 - 34490869

AN - SCOPUS:85115655288

VL - 50

SP - 12448

EP - 12456

JO - Dalton Transactions

JF - Dalton Transactions

SN - 1477-9226

IS - 36

ER -