Popculture in postcolonial literature Motifs of popular culture in Arundhati Roy’s The God of Small Things and Eden Robinson’s Monkey Beach

The reaction of LGa (L = Dipp­(4-(Dipp-imino)­pent-2-en-2-yl)­amide; Dipp: 2,6-diisopropylphenyl) and white phosphorus was revisited. A plethora of unprecedented polyphosphanes in addition to the known monoinserted product LGaP₄ (<b>1</b>) are observed. An optimized synthesis of the hitherto unknown hexaphosphane (LGa)₂P₆ (<b>3</b>) is presented, and its subsequent selective derivatization with Brønsted acids, MeOTf, Ph₂ECl (E = P, As), and NaOCP provides access to a wealth of functionalized hexa- and heptaphosphanes

Nitrogen–Phosphorus(III)–Chalcogen Macrocycles for the Synthesis of Polynuclear Silver(I) Sandwich Complexes

The synthesis of inorganic N–P­(III)-Ch-based macrocycles [−PhP–NMe–PPh–Ch−]₂ (<b>8</b>_<b>Ch</b>; Ch = S, Se) is presented by incorporating two nitrogen, two chalcogen, and four phosphorus atoms. The macrocycles are conveniently obtained via the cyclocondensation reaction of Na₂Ch (Ch = S, Se) with the acyclic dichlorodiphosphazane ClPhP–NMe–PClPh (<b>9</b>). Treatment with elemental sulfur (S₈) or gray selenium (Se_gray) results in an oxidative ring contraction to give 1,3,2,4-thiazadiphosphetidine 2,4-disulfide (<b>10</b>_<b>S</b>) and 1,3,2,4-selenazadiphosphetidine 2,4-diselenide (<b>10</b>_<b>Se</b>), respectively. Macrocycles <b>8</b>_<b>Ch</b> are excellent multidentate ligands for transition metal complexation, as demonstrated by the isolation of mono-, di- tri-, and tetranuclear silver sandwich complexes. The polynuclear silver complexes are comprehensively characterized, including detailed NMR and X-ray analysis

Selective Derivatization of a Hexaphosphane from Functionalization of White Phosphorus

The reaction of LGa (L = Dipp­(4-(Dipp-imino)­pent-2-en-2-yl)­amide; Dipp: 2,6-diisopropylphenyl) and white phosphorus was revisited. A plethora of unprecedented polyphosphanes in addition to the known monoinserted product LGaP₄ (<b>1</b>) are observed. An optimized synthesis of the hitherto unknown hexaphosphane (LGa)₂P₆ (<b>3</b>) is presented, and its subsequent selective derivatization with Brønsted acids, MeOTf, Ph₂ECl (E = P, As), and NaOCP provides access to a wealth of functionalized hexa- and heptaphosphanes

Nitrogen–Phosphorus(III)–Chalcogen Macrocycles for the Synthesis of Polynuclear Silver(I) Sandwich Complexes

The synthesis of inorganic N–P­(III)-Ch-based macrocycles [−PhP–NMe–PPh–Ch−]₂ (<b>8</b>_<b>Ch</b>; Ch = S, Se) is presented by incorporating two nitrogen, two chalcogen, and four phosphorus atoms. The macrocycles are conveniently obtained via the cyclocondensation reaction of Na₂Ch (Ch = S, Se) with the acyclic dichlorodiphosphazane ClPhP–NMe–PClPh (<b>9</b>). Treatment with elemental sulfur (S₈) or gray selenium (Se_gray) results in an oxidative ring contraction to give 1,3,2,4-thiazadiphosphetidine 2,4-disulfide (<b>10</b>_<b>S</b>) and 1,3,2,4-selenazadiphosphetidine 2,4-diselenide (<b>10</b>_<b>Se</b>), respectively. Macrocycles <b>8</b>_<b>Ch</b> are excellent multidentate ligands for transition metal complexation, as demonstrated by the isolation of mono-, di- tri-, and tetranuclear silver sandwich complexes. The polynuclear silver complexes are comprehensively characterized, including detailed NMR and X-ray analysis

Silver Indium Telluride Semiconductors and Their Solid Solutions with Cadmium Indium Telluride: Structure and Physical Properties

Ag_0.8In_2.4Te₄ (= AgIn₃Te₅) and Ag_0.5In_2.5Te₄ (= AgIn₅Te₈) form solid solutions with CdIn₂Te₄, which are interesting as materials for photovoltaics or with respect to their thermoelectric properties. The corresponding crystal structures are related to the chalcopyrite type. Rietveld refinements of high-resolution synchrotron powder diffraction data measured at K-absorption edges of Cd, Ag, In, and Te and electron diffraction reveal the symmetry as well as the element and vacancy distribution in Ag_0.8In_2.4Te₄ (= AgIn₃Te₅)/Ag_0.5In_2.5Te₄ (= AgIn₅Te₈) mixed crystals such as Ag_0.25Cd_0.5In_2.25Te₄ and Ag_0.2Cd_0.75In_2.1Te₄. All compounds of the solid solution series (CdIn₂Te₄)_<i>x</i>(Ag_0.5In_2.5Te₄)_1–<i>x</i> exhibit the HgCu₂I₄ structure type (space group <i>I</i>4̅2<i>m</i>) with completely ordered vacancies but disordered cations. The uniform cation distribution and thus the local charge balance are comparable to that of CdIn₂Te₄. In contrast, Ag_0.8In_2.4Te₄ (= AgIn₃Te₅) crystallizes in the space group <i>P</i>4̅2<i>c</i> with disordered cations and partially ordered vacancies. This is corroborated by bond-valence sum calculations and the fact that there is a Vegard-like behavior for compounds with 0.5 < <i>x</i> in the pseudobinary system (CdIn₂Te₄)_<i>x</i>(Ag_0.8In_2.4Te₄)_1–<i>x</i>. Owing to the different structures, there is no complete solid solution series between CdIn₂Te₄ and AgIn₃Te₅. All compounds in this work are n-type semiconductors with a low electrical conductivity (∼1 S/m) and rather high absolute Seebeck coefficients (up to −750 μV/mK; 225 °C). Electrical band gaps (<i>E</i>_g) determined from the Seebeck coefficients as well as (more reliably) from the electrical conductivity range between 0.19 and 1.13 eV

Reductive Ring Opening of a Cyclo-Tri(phosphonio)methanide Dication to a Phosphanylcarbodiphosphorane: <i>In Situ</i> UV-Vis Spectroelectrochemistry and Gold Coordination

The formal two-electron reduction of the cyclo-tri­(phosphonio)­methanide dication <b>1</b>²⁺ results in a ring-opening reaction via C–P bond cleavage to yield the unique phosphanyl-functionalized carbodiphosphorane <b>2</b>. <i>In situ</i> spectroelectrochemical investigations of the reduction of dication <b>1</b>²⁺ and the oxidation of <b>2</b> give insights into the mechanism of this unusual and reversible bond cleavage reaction. Compound <b>2</b> features in total three lone pairs of electrons, facilitating the preparation of mono-, di-, and trigold complexes

Condensation Reactions of Chlorophosphanes with Chalcogenides

A high-yielding and facile synthesis for diphosphane monochalcogenides (<b>1</b>_Ch^(R)) and their constitutional isomers, diphosphanylchalcoganes (<b>2</b>_Ch^(R)), was developed, featuring a condensation reaction between chlorophosphanes (R₂PCl) and sodium chalcogenides (Na₂Ch, Ch = S, Se, (Te)). The optimized protocol selectively yields either <b>1</b>_Ch^(R) (R₂(Ch)­PPR₂) or <b>2</b>_Ch^(R) (Ch­(PR₂)₂) depending upon the steric demand of the substituents R. Reaction pathways consistent with the distinct reaction outcomes are proposed. The application of <b>1</b>_Ch^(R) and <b>2</b>_Ch^(R) as an interesting class of ligands is exemplarily demonstrated by the preparation of selected transition metal complexes

Chiral Phosphapalladacycles as Efficient Catalysts for the Asymmetric Hydrophosphination of Substituted Methylidenemalonate Esters: Direct Access to Functionalized Tertiary Chiral Phosphines

A chiral palladacycle-promoted enantioselective asymmetric hydrophosphination of substituted methylidenemalonate esters using diphenylphosphine that provides direct access to chiral tertiary phosphines is reported. Screening of three easily accessible C,N and C,P palladacycles as catalysts for this synthetic scenario provided insights into critical factors in catalyst design that influence the activation and stereochemistry in Pd­(II)-catalyzed asymmetric P–H addition reactions involving such activated substrates

Toward Full Zigzag-Edged Nanographenes: <i>peri</i>-Tetracene and Its Corresponding Circumanthracene

Zigzag-edged nanographene with two rows of fused linear acenes, called as n-<i>peri</i>-acene (n-PA), is considered as a potential building unit in the arena of organic electronics. n-PAs with four (<i>peri</i>-tetracene, <b>4-PA</b>), five (<i>peri</i>-pentacene, <b>5-PA</b>) or more benzene rings in a row have been predicted to show open-shell character, which would be attractive for the development of unprecedented molecular spintronics. However, solution-based synthesis of open-shell n-PA has thus far not been successful because of the poor chemical stability. Herein we demonstrated the synthesis and characterization of the hitherto unknown <b>4-PA</b> by a rational strategy in which steric protection of the zigzag edges playing a pivotal role. The obtained <b>4-PA</b> possesses a singlet biradical character (<i>y</i>₀ = 72%) and exhibits remarkable persistent stability with a half-life time (<i>t</i>_1/2) of ∼3 h under ambient conditions. UV–vis–NIR and electrochemical measurements reveal a narrow optical/electrochemical energy gap (1.11 eV) for <b>4-PA</b>. Moreover, the bay regions of <b>4-PA</b> enable the efficient 2-fold Diels–Alder reaction, yielding a novel full zigzag-edged circumanthracene

Toward Full Zigzag-Edged Nanographenes: <i>peri</i>-Tetracene and Its Corresponding Circumanthracene

Zigzag-edged nanographene with two rows of fused linear acenes, called as n-<i>peri</i>-acene (n-PA), is considered as a potential building unit in the arena of organic electronics. n-PAs with four (<i>peri</i>-tetracene, <b>4-PA</b>), five (<i>peri</i>-pentacene, <b>5-PA</b>) or more benzene rings in a row have been predicted to show open-shell character, which would be attractive for the development of unprecedented molecular spintronics. However, solution-based synthesis of open-shell n-PA has thus far not been successful because of the poor chemical stability. Herein we demonstrated the synthesis and characterization of the hitherto unknown <b>4-PA</b> by a rational strategy in which steric protection of the zigzag edges playing a pivotal role. The obtained <b>4-PA</b> possesses a singlet biradical character (<i>y</i>₀ = 72%) and exhibits remarkable persistent stability with a half-life time (<i>t</i>_1/2) of ∼3 h under ambient conditions. UV–vis–NIR and electrochemical measurements reveal a narrow optical/electrochemical energy gap (1.11 eV) for <b>4-PA</b>. Moreover, the bay regions of <b>4-PA</b> enable the efficient 2-fold Diels–Alder reaction, yielding a novel full zigzag-edged circumanthracene