5035-52-9Relevant articles and documents
Compounds of the types Pn(pyS)3(Pn = P, As, Bi; PyS: Pyridine-2-thiolate) and Sb(pyS)xPh3-x(x = 3-1); Molecular structures and electronic situations of the Pn atoms
W?chtler, Erik,Gericke, Robert,Block, Theresa,Gerke, Birgit,P?ttgen, Rainer,Wagler, J?rg
, p. 103 - 118 (2021/02/05)
The compounds Pn(pyS)3 (Pn = P, As, Sb, Bi) were synthesized from the respective chloride (Pn = P, As, Sb) or nitrate (Bi), pyridine-2-thiol (pySH) and triethylamine (NEt3) as a supporting base in THF (P, Sb), CHCl3 (As) or methanol (Bi). Sb(pyS)3 was also obtained from the reaction of SbCl3 with LipyS (prepared in situ) in methanol. The compounds Sb(pyS)2Ph and Sb(pyS)Ph2 were prepared in a one-pot reaction starting from SbCl3 and SbPh3 (1:1 ratio). Upon Cl/pyS substitution, the resulting reaction mixture allows for a facile separation of the products in hot hexane. P(pyS)3 and As(pyS)3 crystallize isostructurally to the reported structure of Sb(pyS)3 with κ-S-bound pyS ligands. These crystal structures feature close Pn···Pn contacts which are most pronounced for the arsenic derivative. Bi(pyS)3 adopts a different molecular structure in the solid state, which features two chelating (κ2-S,N-pyS) ligands and a κ-S-bound ligand. The presence of N→Bi interactions between the nitrogen atom of the κ-S-pyS ligand and the Bi atom of another molecule renders this structure a polymer chain along the crystallographic b axis with BiBi van-der-Waals contacts. The structures of this set of Pn(pyS)3 compounds were also studied in solution using 1H NMR spectroscopy, revealing equivalent pyS ligands in discrete Pn(pyS)3 molecules. The molecular structure of Sb(pyS)Ph2 was optimized by quantum chemical methods, and a comparison with the structures reported for the other Sb/pyS/Ph combinations reveals Sb(pyS)2Ph to feature the strongest Sb···N interactions with the κ-S-pyS ligand. The results of 1H NMR spectroscopic investigations of the compounds Sb(pyS)xPh3-x (x = 3-0) suggest the Ph protons in ortho position to be incorporated into intramolecular C-H···S contacts for x = 2 and 1. Natural localized molecular orbital (NLMO) calculations were employed in order to gain insights into the electronic situations of the Pn atoms and Pn-R bonds (R = S, C), especially for the effects caused by formal substitution of Pn in the compounds Pn(pyS)3 and the ligand patterns in the compounds Sb(pyS)xPh3-x (x = 3-0). For the latter series of compounds, the electronic situation of the Sb atom was further studied by 121Sb M?ssbauer spectroscopy, providing a correlation between the calculated electron density at Sb [ρ(0)] and the experimentally observed isomer shift δ. The missing link between group 15 and group 13 metal compounds of the type M(pyS)3, compound Al(pyS)3, was synthesized in this work. In the solid state (confirmed crystallographically), the mer isomer of this tris-chelate complex with distorted octahedral Al coordination sphere was found. This coordination mode was confirmed for the solution state (CDCl3) by 1H and 13C NMR spectroscopy at T = -40 °C.
Catalysis with Pnictogen, Chalcogen, and Halogen Bonds
Benz, Sebastian,Poblador-Bahamonde, Amalia I.,Low-Ders, Nicolas,Matile, Stefan
supporting information, p. 5408 - 5412 (2018/03/23)
Halogen- and chalcogen-based σ-hole interactions have recently received increased interest in non-covalent organocatalysis. However, the closely related pnictogen bonds have been neglected. In this study, we introduce conceptually simple, neutral, and mon
Structural, spectroscopic and computational examination of the dative interaction in constrained phosphine-stibines and phosphine-stiboranes
Chalmers, Brian A.,Bühl, Michael,Athukorala Arachchige, Kasun S.,Slawin, Alexandra M. Z.,Kilian, Petr
supporting information, p. 7520 - 7531 (2015/05/13)
Abstract A series of phosphine-stibine and phosphine-stiborane peri-substituted acenaphthenes containing all permutations of pentavalent groups -SbClnPh4-n (5-9), as well as trivalent groups -SbCl2, -Sb(R)Cl, and -SbPh2 (2-4, R=Ph, Mes), were synthesised and fully characterised by single crystal diffraction and multinuclear NMR spectroscopy. In addition, the bonding in these species was studied by DFT computational methods. The P-Sb dative interactions in both series range from strongly bonding to non-bonding as the Lewis acidity of the Sb acceptor is decreased. In the pentavalent antimony series, a significant change in the P-Sb distance is observed between -SbClPh3 and -SbCl2Ph2 derivatives 6 and 7, respectively, consistent with a change from a bonding to a non-bonding interaction in response to relatively small modification in Lewis acidity of the acceptor. In the SbIII series, two geometric forms are observed. The P-Sb bond length in the SbCl2 derivative 2 is as expected for a normal (rather than a dative) bond. Rather unexpectedly, the phosphine-stiborane complexes 5-9 represent the first examples of the σ4P→σ6Sb structural motif. A complex situation: The strength of a dative phosphine-stiborane (P-Sb) interaction increases with stepwise replacement of phenyl groups on antimony atom with chloride groups. As the Lewis acidity is increased in regular steps (see figure), essentially linear response is observed initially, however then a sudden change in the P-Sb distance takes place during one particular step. This is consistent with a sudden switch from a non-bonding to a bonding interaction, that is, a discrete rather than continuum response.
