The syntheses and full characterizations of the peri‐substituted naphthalenes (Nap) and acenaphthenes (Ace) 1‐Br‐8‐(Ph2P)‐Nap (1a) and 5‐Br‐6‐(Ph2P)‐Ace (1b), as well as their derivatives 1‐Br‐8‐[Ph2P(E)]‐Nap [E = CH3+ (counterion I–) (2a); E = O (3a); E = S (4a); E = Se (5a)] and 5‐Br‐6‐[Ph2P(E)]‐Ace [E = CH3+ (counterion I–) (2b); E = O (3b); E = S (4b); E = Se (5b)] are reported. In order to quantify the energetic and electronic effects of the peri‐interactions, an additional set of molecules, 1c–5c, with the bromine atom and the Ph2P(E) fragment on opposite sides of the naphthalene group was generated, which serves as reference because 1c–5c exhibit negligible peri‐interactions. The molecular arrangements of all 15 compounds were optimized at the B3PW91/6‐311+G(2df, p) level of theory. The analysis of the peri‐interactions was not only based on the inspection of the molecular arrangement and energies alone, but extended to a set of real‐space bonding indicators (RSBI). These indicators were derived from theoretically calculated electron densities and pair densities, respectively. Particularly, the stockholder, Atoms‐In‐Molecules (AIM) and Electron‐Localizability‐Indicator (ELI‐D) space partitioning schemes were used to produce Hirshfeld surfaces (HS), bond topological properties and basins of localized bonding and nonbonding electron pairs. Since 1c–5c are 35–58 kJ·mol–1 lower in energy than their counterparts 1a–5a, the hypothesis of a mainly repulsive peri‐interaction in 1a/b–5a/b was confirmed. The shapes and contact patterns of the HSs of atoms and fragments involved in the peri‐interactions (Br, P, E = CH3+, O, S, Se) reveal that only in 1a and 1b are peri‐interactions exhibited between the bromine and the phosphorus atoms. In all other cases (2a/b–5a/b), the interaction mainly occurs between the bromine atom and the E atom/fragment. According to the bond topological properties and the electron populations within the (non)bonding ELI‐D basins, which both are almost unaffected by the Br‐P/E peri‐interaction, sterical interactions are characterized essentially by geometrical and energetical changes.

Ace-5-TeMes]O 3 SCF 3 ( 16) is reported (Ace = acenaphthyl). The synthesis of 7−15 was achieved either by a salt metathesis reaction of 5-i-Pr 2 P-Ace-6-Li with TeCl 2 •TMTU (8), TeBr 2 •TMTU (9), and TeI 4 (10 + 11) or by the aryl cleavage reaction of 6-R 2 E-Ace-5-TeMes (E = P, As, Sb; R = Ph, i-Pr) with HgCl 2 (7), I 2 (12), and HO 3 SCF 3 (13−15). The reaction of 5 with triflic acid gave also rise to the formation of [6-PhSb-Ace-5-TeMes]O 3 SCF 3 (16). All compounds have been characterized by multinuclear NMR spectroscopy and single-crystal X-ray diffraction. Complementary DFT studies including relaxed potential energy scans (PES) and subsequent topological analysis of the resulting electron and pair densities according to the AIM and ELI-D partitioning schemes were performed for the aryltellurenyl chlorides [6-Ph 2 P-Ace-5-Te]Cl, [8-Me 2 N-Nap-1-Te]Cl, and [8-Me 2 P-Nap-1-Te]Cl in the gas phase and in MeCN solution, whereby the Te−Cl distances were systematically varied. The same analyses were carried out for the fully optimized [6-R 2 E-Ace-5-Te] + cations (E = P, As, Sb) and compared to those of the previously studied intermolecularly stabilized [R 3 ETeMes] + cations (E = P, As, Sb).

The organotin precursors 6-Br-Ace-5-SnBu 3 (6, Ace = acenaphthyl) and 6-Ph 2 E-Ace-5-SnBu 3 (7a: E = P; 7b: E = As; 7c: E = Sb) were prepared and used for the synthesis of organogold complexes, namely, the homodinuclear arylgold(I) species (6-Ph 2 E-Ace-5-Au) 2 (8a: E = P; 8b: E = As; 8c: E = Sb), arylgold(III) dichloride 6-Ph 2 P-Ace-5-AuCl 2 (9), diarylgold(III) chloride [trans-(6-Ph 2 P-Ace-5-) 2 Au]Cl ([10]Cl), as well as the heterodinuclear gold complexes 6-Ph 2 P(AuX)-Ace-5-Au(AsPh 3 ) (11a: X = Cl; 11b: X = Br). Compounds 8a -8c, 11a, and 11b show significant aurophilic interactions, which are related to their photolumines- [a] naphth-5-yl)mercury and inorganic gold salts. [9] Due to the kinetic instability of the reported Hg-Au complexes, the formation of the cis-bis(6-diphenylphosphinoacenaphth-5-yl)gold cation [5] + was observed (Scheme 1). We now report on a series of peri-substituted (6-diphenylpnicogenoacenaphth-5-yl)gold compounds, which show substantial aurophilic interactions as well as green-yellow photoluminescence in solution and, in some cases, also in the solid state. These compounds were characterized by NMR, UV/Vis, and photoluminescence spectroscopy as well as X-ray crystallography. In addition, the aurophilic interactions and photoluminescence properties were characterized theoretically employing density functional theory (DFT) and time-dependent density functional theory (TD-DFT). Determination of a set of real-space bonding indicators (RSBIs), derived from the electron density (ED), facilitates straight-forward characterization of chemical bonds in complex molecular systems. The wide-spread topological approach according to the Atoms-In-Molecules (AIM [10] ) space-partitioning provides atomic properties, such as charges and volumes, a distinct bond paths motif, as well as bond properties, which are used to analyze various kinds of chemical interactions. [11] A recent approach relies on the reduced density gradient, s(r) = [1/2-(3π 2 ) 1/3 ]|∇ρ|/ρ 4/3 , which is displayed in a way to uncover regions in space where non-covalent interactions (NCI [12] ) occur. By mapping the ED times the sign of the second eigenvalue of the Hessian [sign(λ 2 )ρ] on iso-surfaces of s(r), different contact types including steric/repulsive (λ 2 > 0), van der Waals-like (λ 2 ≈ 0), and attractive (λ 2 < 0) interactions can be assigned. In complementary fashion, the computed electron pair densities may be analyzed according to the topological Electron Localizability Indicator (ELI-D [13] ) method, which divides real-space into basins of localized electron pairs. By applying this tool, which provides electron populations of bonds and lone-pairs, effects of electron redistribution due to subtle structural changes become visible. As shown in previous studies, the combined use of AIM, NCI, and ELI-D is superior to the restriction to one type of RSBI as different aspects of atom-atom interactions (bond Scheme 2. Synthesis of the organotin precursors 6 and 7a -7c. 648 polarities, degree of covalency, etc.) may be...

The syntheses of the diaryltelluride 6-Ph 2 P(O)-Ace-5-TeMes (1O), the tellurenyl(II) chlorides 6-Ph 2 P(E)-Ace-5-TeCl (2O, E = O; 2S, E = S; 2Se, E = Se), the ditelluroxonium(IV) bis(triflate) [6-Ph 2 P(O)-Ace-5-TeO] 2 (O 3 SCF 3 ) 2 (3O), the diaryltellurium(IV) dichloride 6-Ph 2 P(O)-Ace-5-TeMesCl 2 (4O), the diarylhalotelluronium(IV) polyhalides [6-Ph 2 P(O)-Ace-5-TeMesBr]Br 3 (5O) and [6-Ph 2 P(O)-Ace-5-TeMesI] 2 I 8 (6O), and the aryltellurium(IV) trihalides 6-Ph 2 P(O)-Ace-5-TeX 3 (7O, X = Cl; 8O, X = Br; 9O, X = I) are reported. All compounds have been characterized experimentally by means of multinuclear NMR spectroscopy as well as single-crystal X-ray crystallography. The diverse P−E•••Te bonding situations (E = O, S, Se) in the peri region have also been investigated in detail by complementary DFT studies including the calculation of peri interaction energies (α-PIE) as well as topological analyses of the electron and pair densities according to the AIM and ELI-D space-partitioning schemes and evaluation of noncovalent bonding aspects applying the NCI index. To illustrate the different bond situations, appropriate Lewis formula representations have been suggested.

The reaction of the previously known bis(6-diphenylphosphinoacenaphthyl-5-)telluride (6-Ph2P-Ace-5-)2Te (IV) with (CO)5ReCl and (CO)5MnBr proceeded with the liberation of CO and provided fac-(6-Ph2P-Ace-5-)2TeM(X)(CO)3 (fac-1: M = Re, X = Cl; fac-2: M = Mn, X = Br), in which IV acts as bidentate ligand. In solution, fac-1 and fac-2 are engaged in a reversible equilibrium with mer-(6-Ph2P-Ace-5-)2TeM(X)(CO)3 (mer-1: M = Re, X = Cl; mer-2: M = Mn, X = Br). Unlike fac-1, fac-2 is prone to release another equivalent of CO to give (6-Ph2P-Ace-5-)2TeMn(Br)(CO)2 (3), in which IV serves as tridentate ligand.