Pentacarbonyl[2‐(2′‐pyridyl)quinoxaline‐κN⁴]tungsten: A Combined Study of Its Conformational and Electronic Structure Based on Experimental and DFT‐TDDFT Data

Abstract

Keywords: Pentacarbonyl complexes / 2-(2-Pyridyl)quinoxaline / Tungsten / DFT calculations / TD-DFT calculations / Pi stacking Photolysis of W(CO) 6 in the presence of 2-(2Ј-pyridyl)quinoxaline (pq) results in the formation of W(CO) 4 (pq) via an intermediate product W(CO) 5 (N 4 -pq) (1). In 1 the pq ligand that has three nitrogen atoms -two pyridine and one quinoxaline type -is coordinated in a monodentate fashion. This is the first example, where the pq ligand is coordinated in a monodentate fashion and especially from a quinoxaline nitrogen atom (N 4 ). Complex 1 has been fully characterized and its crystal structure has unambiguously demonstrated that pq is preferably coordinated through N 4 rather than the N 1 and N 1Ј atoms, while its packing is governed by π-π interactions and hydrogen bonds. The almost perfect "face-to-face" alignment of the condensed quinoxaline rings is attributed

Synthesis, DNA-Binding, Anticancer Evaluation, and Molecular Docking Studies of Bishomoleptic and Trisheteroleptic Ru-Diimine Complexes Bearing 2-(2-Pyridyl)-quinoxaline

“…Furthermore, in both complexes, the metal-N quinoxaline bond length is elongated with respect to the metal-N pyridyl bond length, and this difference can be explained in terms of the less σ-donating ability of the quinoxaline N-atom with respect to the N pyridyl moiety. In support of this observation, it is instructive to compare the crystal structures of several latetransition metal complexes that contain the 2, 2′-pq ligand, which were reported by us, in particular, complexes with Mo [46], Re [18,47,48], and W [49,50]. In all cases, the same trend for the metal-N quinoxaline and metal-N pyridyl bond lengths, found in 1 and 2, is also found for these complexes (Table 5).…”

Synthesis, characterization, DFT studies and DNA binding of mixed platinum (II) complexes containing quinoxaline and 1,2-dithiolate ligands

“…and can be used as antibacterial, antiviral, anticancer, antihelmintic and insecticidal agent [30]. Besides, it adopts a planar conformation when it chelates to a metal ion [31][32][33].…”

Syntheses and Properties of Dinuclear Group 6 Metal Complexes with the Zwitterionic Sulfur Donor Ligand Bis(N,N-diethylamino)carbeniumdithiocarboxylate

“…In addition, the high contribution of the −CS 2 moiety in the HOMO describes the W−EtL π back-bonding, indicating that the HOMO is spectroscopically the most important member of the HOMO manifold. In general, the group 6 mononuclear complexes ([M(CO) 4 L] 39 and [M(CO) 5 L] 40 ) have the same electron configuration, and the three HOMOs have similar energies. In complex 3, the HOMO to HOMO-5 energy levels are broadened because of the contributions of the asymmetric metal centers and EtL.…”