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Thiele's Hydrocarbons (THs) featuring a 9,10‐anthrylene core with switchable geometric and electronic configurations offer exciting possibilities in advanced functional materials. Despite significant advances in main group‐based diradicaloids in contemporary chemistry, main group THs containing an anthrylene cores have remained elusive, primarily due to the lack of straightforward synthetic strategies and the inherent high reactivity of these species. In this study, we utilize an anthracene‐based phosphine synthon to demonstrate, for the first time, a facile and high‐yielding synthetic strategy for robust P‐functionalized overcrowded ethylenes (OCEs) within the TH family. These OCEs feature a non‐symmetric environment, incorporating (thio) xanthyl and phosphaalkene termini. We systematically probe the electronic structures of these derivatives to illustrate the impact of the isolobal phosphaalkene motif on the quinoidal/diradicaloid character. Notably, the compounds exhibit dynamic redox behavior, leading to orthogonally twisted conformational changes upon oxidation, with a kinetically locked redox‐couple. [ABSTRACT FROM AUTHOR]

The stepwise reduction of the highly contorted truxene‐based triphosphaalkene 1 using KC8 led to the isolation of mono‐, di‐, and tri‐anionic species. The solid‐state molecular structures of mono‐ and diradical anionic species were elucidated by single crystal X‐ray diffractions, revealing elongated P−C bonds and a pronounced “indene” aromatization compared to the parent system. All three radical species displayed distinct Electron Paramagnetic Resonance (EPR) spectra, providing compelling evidence for the open‐shell electronic configuration of both the diradical and triradical species—an observation unprecedented in any previously reported phosphorous‐based anionic polyradicals. Mulliken spin density calculations revealed a dominant localization of radical spin on a single phosphorous atom in the monoanion. In the dianion, spin localization is observed on two phosphorous atoms (~34 % each), with a minor contribution from the third phosphorous (0.13 %), while the trianion demonstrates a uniform distribution of spin density (~30 %) across each phosphorous atom. [ABSTRACT FROM AUTHOR]

The oxidation reaction of L-tellurocystine, [Te2{CH2CH(NH3+)COO−}2] (4) with H2O2 in the presence of HBr resulted in the formation of cyclic, zwitterionic organotellurolate(IV) species, namely [Te−{CH2CH(NH3+)COO}(Br)3] (5). The H2O2 oxidation of Te-protected tellurocysteine derivatives [RTe{CH2CH(NH2)COOH}] [R = C6H5 (6) and 4-MeC6H4 (7)] in the presence of HCl resulted in the formation of chlorotellurane species [(C6H5)Te{CH2CH(NH3+)COOH}(Cl)2]Cl (8) and [(4-MeC6H5)Te{CH2CH(NH3+)COO}(Cl)]Cl (9), respectively. The oxidation reaction of diorganodiselenides R2Se2 [R = 4-MeC6H4 (10), R = 4-OMeC6H4 (11), R = 3,4-Me2C6H3 (12) and R = 2,4,6-Me3C6H2 (13)] with H2O2 afforded homoleptic diorganoselenones R2SeO2 [R = 4-MeC6H4 (14), R = 4-OMeC6H4 (15), R = 3,4-Me2C6H3 (16) and R = 2,4,6-Me3C6H2 (17)], respectively. The synthesized compounds were thoroughly characterized by multinuclear NMR (1H, 13C, 125Te/77Se), FT-IR spectroscopy, ESI-MS and elemental analysis. The molecular structures of the compounds were determined by single crystal X-ray diffraction studies. [ABSTRACT FROM AUTHOR]

A simple methodology for the synthesis of heteroleptic diorganotelluride [2,6‐(Me2NCH2)2C6H3]TenBu (1) and homoleptic diorganotelluride [2,6‐(Me2NCH2)2C6H3]2Te (2) is reported. The halogenation reactions of diorganotelluride 1 are studied. In particular, the reaction of 1 with Br2 resulted in the isolation of a monoorgano dibromotelluronium(IV) cation, namely [2,6‐(Me2NCH2)2C6H3TeBr2]·Br3 ([3]·Br3). The reaction of [3]·Br3 with K2PdCl4 afforded a monoorgano mixed dihalotelluronium(IV) cation, [2,6‐(Me2NCH2)2C6H3TeClBr]·PdBr4 ([4]·PdBr4). When diorganotelluride 1 was treated with I2, the reaction afforded the tellurenium(II) cation, [2,6‐(Me2NCH2)2C6H3Te]·I2·I3 ([5]·I2·I3). The reaction of 1 with HgCl2 resulted in the isolation of dimeric diorganoditelluroxonium(IV) cation, [2,6‐(Me2NCH2)2C6H3Te(µ‐O)]2·Hg2Cl6 ([6]·Hg2Cl6). A similar diorganoditelluroxonium(IV) cation, namely [2,6‐(Me2NCH2)2C6H3Te(µ‐O)]2·2Br ([6]·2Br) was also obtained by the reaction of 1 with Br2 and NaOH. The crystallographic studies suggest that for each compound, both the N atoms from the pendant arms make strong Intramolecular Chalcogen Bonding (IChB) interactions with the Te center(s). The presence of a strong N→Te IChB interaction in the synthesized compounds was further validated by DFT calculations. [ABSTRACT FROM AUTHOR]

In the title salt, di-μ-oxido-bis­{2,6-bis­[(di­methyl­amino)­meth­yl]phenyl-κC¹}tellurium(­IV) bis[tri­chlorido­(dimethyl sulfoxide-κS)platinate(II)], (C24H38N4O2Te2)[PdCl3(C2H6OS)]2, which crystallizes in the triclinic space group P1̅, each Te atom is in a distorted five-coordinated TeO2N2C square-pyramidal geometry (τ values of 0.026 and 0.001) with the C atoms of the phenyl rings occupying the apical positions. The phenyl rings in the [C24H38N4O2Te2]2+ cation are in a cis arrangement to enable this species to participate in Te...Cl cation–anion inter­actions. There are also C—H...O inter­actions involving the dimethyl sulfoxide ligands and numerous cation–anion and anion–anion C—H...Cl inter­actions, which link the ions into a complex three-dimensional array. [ABSTRACT FROM AUTHOR]

The oxidation reaction of unsymmetrical diorganotellurides, namely, bis[2-{(dimethylamino)methyl}aryl]tellurides [aryl = phenyl (6), 2-methylphenyl (7), 2,6-dimethylphenyl (8) and 2,6-diisopropylphenyl (9)] with meta-chloroperbenzoic acid afforded the first examples of tetraorganoditelluronic acids, [RR′Te(μ-O)(OH)2]2, where R = 2-NMe2CH2C6H4, R′ = C6H5 (10), 2-MeC6H4 (11), 2,6-MeC6H3 (12) and 2,6-iPrC6H3 (13). The structures of tetraorganoditelluronic acids 10–13 were authenticated by single crystal X-ray diffraction studies. From the molecular structures of 10–13, it was observed that the sp3 N-donor atoms, which were initially involved in intramolecular Te…N bonding interactions in diorganotellurides 6–9, did not interact with the tellurium atoms in tetraorganoditelluronic acids 10–13. The 125Te chemical shifts for 10–13 were considerably downfield shifted as compared with the values observed for the corresponding tellurides 6–9. The relative stabilities of the tetraorganoditelluronic acids 10–13 with respect to their lighter analogues (S and Se) have been assessed using DFT calculations. [ABSTRACT FROM AUTHOR]

The oxidation reaction of unsymmetrical diorganotellurides, namely, bis[2-{(dimethylamino)methyl}aryl]tellurides [aryl = phenyl (6), 2-methylphenyl (7), 2,6-dimethylphenyl (8) and 2,6-diisopropylphenyl (9)] with meta-chloroperbenzoic acid afforded the first examples of tetraorganoditelluronic acids, [RR′Te(μ-O)(OH)2]2, where R = 2-NMe2CH2C6H4, R′ = C6H5 (10), 2-MeC6H4 (11), 2,6-MeC6H3 (12) and 2,6-iPrC6H3 (13). The structures of tetraorganoditelluronic acids 10–13 were authenticated by single crystal X-ray diffraction studies. From the molecular structures of 10–13, it was observed that the sp3 N-donor atoms, which were initially involved in intramolecular Te…N bonding interactions in diorganotellurides 6–9, did not interact with the tellurium atoms in tetraorganoditelluronic acids 10–13. The 125Te chemical shifts for 10–13 were considerably downfield shifted as compared with the values observed for the corresponding tellurides 6–9. The relative stabilities of the tetraorganoditelluronic acids 10–13 with respect to their lighter analogues (S and Se) have been assessed using DFT calculations. [ABSTRACT FROM AUTHOR]

A convenient approach for the synthesis of alicyclic selenospirocycles, 24 and 25, stabilized by intramolecular chalcogen bonding (IChB) is reported by the reaction of 5‐alkyl‐2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene derivatives {alkyl=H (22), Me (23)} with in situ generated disodium diselenide (Na2Se2). However, when 2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene, 22 is condensed with aniline or 4‐methoxyaniline and the resulting Schiff bases 26 and 27 are subjected to identical reactions, the Schiff bases undergo cyclisation to afford brightly colored, fused 1,6‐diaza‐6a‐selenapentalene derivatives 28–29, instead of the expected selenospirocycles. The aromatic nucleophilic substitution (SNAr) reaction of N‐(2‐bromo‐3‐nitrobenzyl)naphthylamine, 33 with nBuSeLi affords N‐[2‐(butylselanyl)‐3‐nitrobenzyl]naphthylamine, 34. The bromination of 34 results in the formation of cyclic isoselenazolines, 35. Selenospirocycles 24 and 25, 1,6‐diaza‐6a‐selenapentalenes 28 and 29 and isoselenazoline 35 are authenticated by single‐crystal X‐ray diffraction studies. Compounds 24, 25 and 35 are stabilized by intramolecular secondary interactions. The reaction of 5‐alkyl‐2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene derivatives (alkyl=H, Me) with in situ generated disodium diselenide (Na2Se2) affords alicyclic selenospirocycles. However, a similar reaction of the Schiff base derivatives of 2‐chloro‐1‐formyl‐3‐hydroxymethylenecyclohexene with Na2Se2 leads to the formation of highly colored azapentalenes. The attempted synthesis of selenospirocycle from N‐[2‐(butylselanyl)‐3‐nitrobenzyl]naphthylamine results in the formation of isoselenazolines. [ABSTRACT FROM AUTHOR]

Owing to the strict hard/soft dichotomy between the lanthanoids and tellurium atoms, and the strong affinity of lanthanoid ions for high coordination numbers, low-coordinate, monomeric lanthanoid tellurolate complexes have remained elusive as compared to the lanthanoid complexes with lighter group 16 elements (O, S, and Se). This makes the development of suitable ligand systems for low-coordinate, monomeric lanthanoid tellurolate complexes an appealing endeavor. In a first report, a series of low-coordinate, monomeric lanthanoid (Yb, Eu) tellurolate complexes were synthesized by utilizing hybrid organotellurolate ligands containing N-donor pendant arms. The reaction of bis[2-((dimethylamino)methyl)phenyl] ditelluride, 1 and 8,8'diquinolinyl ditelluride, 2 with Ln 0 metals (Ln=Eu, Yb) resulted in the formation of monomeric complexes [Ln II (TeR) 2 (Solv) 2 ] [R=C 6 H 4 -2-CH 2 NMe 2 ] [3: Ln=Eu, Solv=tetrahydrofuran; 4: Ln=Eu, Solv=acetonitrile; 5: Ln=Yb, Solv=tetrahydrofuran; 6: Ln=Yb, Solv=pyridine] and [Eu II (TeNC 9 H 6 ) 2 (Solv) n ] (7: Solv=tetrahydrofuran, n=3; 8: Solv=1,2-dimethoxyethane, n=2), respectively. Complexes 3-4 and 7-8 represent the first sets of examples of monomeric europium tellurolate complexes. The molecular structures of complexes 3-8 are validated by single-crystal X-ray diffraction studies. The electronic structures of these complexes were investigated using Density Functional Theory (DFT) calculations, which revealed appreciable covalency between the tellurolate ligands and lanthanoids., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

In the title salt, di-μ-oxido-bis-{2,6-bis-[(di-methyl-amino)-meth-yl]phenyl-κ C 1 }tellurium(-IV) bis[tri-chlorido-(dimethyl sulfoxide-κ S )platinate(II)], (C 24 H 38 N 4 O 2 Te 2 )[PdCl 3 (C 2 H 6 OS)] 2 , which crystallizes in the triclinic space group P , each Te atom is in a distorted five-coordinated TeO 2 N 2 C square-pyramidal geometry (τ values of 0.026 and 0.001) with the C atoms of the phenyl rings occupying the apical positions. The phenyl rings in the [C 24 H 38 N 4 O 2 Te 2 ] 2+ cation are in a cis arrangement to enable this species to participate in Te⋯Cl cation-anion inter-actions. There are also C-H⋯O inter-actions involving the dimethyl sulfoxide ligands and numerous cation-anion and anion-anion C-H⋯Cl inter-actions, which link the ions into a complex three-dimensional array., (© Gupta et al. 2020.)