Synthesis, structure and dispersion interactions in bis(1,8-naphthalendiyl)distibine

Abstract

NaphSb1 was synthesized by a reaction of 1,8-dilithionaphthalene NaphLi with SbCl and its solid state structure is reported on. 1 shows intermolecular interactions in the solid state, which were studied by quantum chemical calculations with dispersion corrected density functional theory, supermolecular ab initio approaches and symmetry adapted perturbation theory. The same methods were employed to compare the solid state interactions in the crystal of 1 to those in real (for E = P) and hypothetical (for E = As and Bi) crystal structures of NaphE. Dispersion interactions were found to provide the most important stabilising contribution in all cases, seconded by electrostatic attraction between pnictogen atoms and π-systems of neighbouring naphthyl groups.

Structure and Reactivity of 1,8-Bis(naphthalenediyl)dipnictanes

“… a Calculated at the BP86-D3/def2-TZVPP level of theory (def2-QZVP for E = As, Sb) b E = As ( 1 ), Sb ( 2 , 3 ). c 3 does not show any Sb–Sb single bonds.…”

“…These findings perfectly agree with our predictions from quantum chemical calculations. [57] To rationalize and quantify the intermolecular interactions, DLPNO-CCSD(T) [73][74][75][76][77][78] calculations were performed for the series of Naph2As2, Naph2Sb2 and Naph2Bi2. The intermolecular by interactions in the dimer structures were analyzed using the Local Energy Decomposition (LED) method, [79,80] which allows to express the interaction energy in terms of geometric and electronic preparation, dispersive and non-dispersive contributions (Figure 3).…”

“…Reaction of NaphLi 2 (TMEDA) with AsCl 3 in 3:2 molar ratio at −78 °C proceeded with elimination of LiCl and reduction of the arsenic center as was previously observed in the analogous reaction with SbCl 3 (Scheme ). Diarsane Naph 2 As 2 1 was obtained as light-orange crystalline solid in 52% yield, while the formation of perylene was verified by 1 H NMR spectroscopy.…”

“…[93,94] The shortening of the Sb-Sb bond in 6 points to an increasing p-orbital character of the bonding electrons, which results in slightly shorter Sb-C bond lengths 7), 95.39(7)°). [57] Analogous trends were reported for [Ph4Sb2][Fe(CO)3PPh3] (Sb-Sb 2.8282(7) Å vs. 2.844(1) Å for Sb2Ph4 [95] ), which showed comparable Sb-C bond lengths and C-Sb-C as well as C-Sb-Sb bond angles for the threefold-(Sb-C 2.138(9), 2.145(7) Å, C-Sb-Sb 94.9(2)°, 98.1(2)°, C-Sb-C 98.4(3)°) and fourfold-coordinated Sb atoms (Sb-C 2.130(6) Å, 2.132(7) Å, C-Sb-Sb 98.6(2)°, 100.0(2)°, C-Sb-C 100.5(2)°), respectively. [96] [Me4Sb2][Cr(CO)5]2 [97] also showed shorter Sb-Sb and Sb-C bond lengths as well as wider C-Sb-C and C-Sb-Sb angles compared to Sb2Me4.…”

“…Peri -substituted complexes of group 15 (type I ) − and group 16 elements − as well as mixed group 15/16 compounds − are known (Scheme ), and pnictogen–pnictogen as well as chalcogen–chalcogen interactions have been studied to some extent. Recently, we reported the synthesis of distibane Naph 2 Sb 2 2 (type III ), which was formed by reductive coupling of two Sb­(III) centers as was observed in the reaction of 1,8-dilithionaphthalene NaphLi 2 with PhPCl 2 , yielding Naph­(PPh) 2 (type II ) . The strength of intermolecular Sb···π interactions in the solid state of 2 was analyzed by dispersion-corrected quantum chemical calculations.…”