(B15c5)BiI3(I2): Molecular Benzo-15-Crown-5―BiI3 Complexes Bridged by Iodine Molecules to Chains

Abstract

Abstract:The reaction of bismuth triiodide with iodine and benzo-15-crown-5 in ethanol/dichloromethane yielded red single crystals of (b15c5)BiI 3 (I 2 ) (monoclinic, P2 1 /c (no. 14), a = 1376.9(1), b = 1172.7(1), c = 1700.2(2) pm, β = 115.197(6), V = 2484.1(4)·10 6 pm 3 , Z = 4). Neutral pseudo-octahedral complexes (b15c5)BiI 3 are connected by secondary bonding interactions via iodine molecules to chains. Electronic structure calculations of the neutral complex (b15c5)BiI 3 reveal that the compound can indeed be described as b15c5 interacting with a molecular BiI 3 unit. However, bonding has to be mainly electrostatic as the interactions of the bismuth 6s lone pair with the 2p orbitals of the oxygen atoms of the crown ether are clearly antibonding.

(15‐crown‐5)BiI3 as a Building Block for Halogen Bonded Supramolecular Aggregates

“…The crown ether moiety is disordered over two positions (see Figure S1). BiÀ I and BiÀ O bond lengths are in similar ranges as observed in (benzo-15crown-5)BiI 3 •I 2 [24] ( Table 1). BiÀ I bond lengths and angles are also similar to those observed on the (001) facet of BiI 3 ( Table 1).…”

“…As shown in Figure 5, the onset of absorption is red-shifted for 2 in comparison to 1. This can also be seen in photographs of the [24] BiI 3 , [30] and TIE [32] to a stronger interaction with the TIE units in 2, that may also, as is typical for halogen bonding interactions, [1] We have also determined the optical band gaps of 1 and 2 (see Figure S7) as 2.34 and 2.22 eV, respectively, highlighting the small, but discernable difference between the two. A redshift in absorption bands has also been observed in other metal halide complexes upon interaction with halogen bond donors.…”

“…As shown in Figure 3d, these interactions connect the two building blocks into a corrugated layer, that can be described as a 4 4 ‐square net where one of the iodine atoms of the (15‐crown‐5)BiI 3 moiety connects individual TIE molecules. As shown in Table 1, intramolecular I⋅⋅⋅I interactions in 2 are closer than those found in 1 , BiI 3 or TIE, but I⋅⋅⋅I distances are also larger than those found in (benzo‐15‐crown‐5)BiI 3 ⋅I 2 [24] suggesting a less pronounced interaction than in the iodine adduct.…”

“…Earlier reports on BiX 3 -crown ether complexes [21,22] have shown that in most cases, the crown ether moiety occupied one hemisphere of the Bi 3 + ion, enforcing an arrangement of the halogen atoms that is fairly similar to that found on the (001) facet of BiI 3 , [23] as illustrated in Figure 1. Additionally, an earlier work by Meyer and coworkers had provided a first example of such an aggregate in the form of (benzo-15-crown-5)BiI 3 •I 2 [24] and Bock has shown that halogen bonded aggregates with classic halogen bond donors like TIE could be obtained, for example as (18-crown-6)PbI 2 •TIE. [25] A search in the Cambridge Crystallographic Database [26] reveals that up to now the use of chalcogen-based ligands like crown ethers has been the only way to enforce the trigonal pyramidal shape of BiI 3 in the gas phase [27] within a neutral coordination complex.…”

Electron Density Distribution in 15-Crown-5 and Its Thioanalogs

“…Одной из актуальнейших задач современной химии является переработка радиоактивных отходов [4]. Создание данной технологии сопряжено с рядом трудностей, одной из которых является сильная токсичность радиоактивных соединений, а другойвысокая растворимость получаемых радионуклеотидных комплексов в воде [ Некоторые физико-химических свойства краун-эфиров и их тиоаналогов указаны в [5,6], их уточнение в [7][8][9][10][11][12][13][14][15]. Распределение электронной плотности, как правило, изучают с использованием компьютерных программ [18,20].…”