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Terphenyl(bisamino)phosphines have been identified as effective ligands in cationic gold(I) complexes for the hydroamination of acetylenes. These systems are related to Buchwald phosphines and their steric properties have been evaluated. Effective hydroamination was noted even at low catalyst loadings and a series of cationic gold(I) complexes has been structurally characterized clearly indicating stabilizing effects through gold-arene interactions. [ABSTRACT FROM AUTHOR]

N‐heterocyclic carbenes (NHCs) are a highly important class of ligands in transition metal‐mediated catalysis. Recently, a modification of the NHCs has received considerable interest, the N‐heterocyclic olefins (NHOs) with an exocyclic methylene appended to the NHC. In here we investigated the propensity of NHOs to act as a ligands for Pd0 complexes derived from [Pd2(dvds)3]. The reaction of IPrCH2 and IMesCH2 with the Pd0 precursor [Pd2(dvds)3] resulted in the formation of abnormal N‐heterocyclic carbene complexes [(aIPrCH3)Pd(dvds)] (1) and [(aIMesCH3)Pd(dvds)] (2). DFT calculations were applied to study this isomerization and to reveal the bonding in 1 and 2. In addition, the backbone‐methylated NHOs MeIPrCH2 and mMeIMesCH2 (4) were shown not to undergo the isomerization observed in IPrCH2 and IMesCH2. [ABSTRACT FROM AUTHOR]

The solid-state structure and Raman spectrum of Wannagat's mercurane, Hg[N(SiMe3)2]2 (1), are reported. Crystals were grown from the pure substance by slow cooling to -24 °C. Compound 1 crystallizes in the monoclinic space group P21/c as discrete monomers, which do not display intermolecular mercurophilic interactions. The molecular structure features a nearly linear N-Hg-N scaffold, while the (Me3Si)2N groups are in a staggered conformation with a dihedral angle of 58.3° (average) to each other. This can be attributed to intramolecular dispersion interactions according to DFT calculations. [ABSTRACT FROM AUTHOR]

The solid-state structure and Raman spectrum of Wannagat's mercurane, Hg[N(SiMe3)2]2 (1), are reported. Crystals were grown from the pure substance by slow cooling to -24 °C. Compound 1 crystallizes in the monoclinic space group P21/c as discrete monomers, which do not display intermolecular mercurophilic interactions. The molecular structure features a nearly linear N-Hg-N scaffold, while the (Me3Si)2N groups are in a staggered conformation with a dihedral angle of 58.3° (average) to each other. This can be attributed to intramolecular dispersion interactions according to DFT calculations. [ABSTRACT FROM AUTHOR]

Es werden zwei effiziente Methoden präsentiert, um σ ‐ und π ‐ Elektronen ‐ donierende N ‐ heterocyclische Vinylgruppen an Hauptgruppenelementen (E) zu installieren: Halogensilan ‐ Eliminierung und baseninduzierte E ‐ C Bindungsbildung. Die Platzierung von zwei NHC=CH− ‐ Liganden (NHC=N ‐ heterocyclisches Carben) an einem GeII ‐ Zentrum resultiert in einem zweifach koordinierten Germylen, einem schweren Kongener der flüchtigen Divinylcarbene. Die Fähigkeit dieses vinylischen Ligandengerüstes, als π ‐ Donor hochreaktive Spezies zu stabilisieren wurde des Weiteren durch die Synthese eines dreifach koordinierten Germylium ‐ Kations R3Ge+ gezeigt. Germylene auf Vinyl: N ‐ heterocyclische Vinylliganden ermöglichen die Isolierung des ersten basefreien Divinylgermylens, eines schweren Homologen der Divinylcarbene. Die π ‐ Donor ‐ Fähigkeit der Vinylliganden wird durch die Synthese des dreifach koordinierten Germylium ‐ Kations R3Ge+ unterstrichen. [ABSTRACT FROM AUTHOR]

Two efficient methods are presented to install σ- and π-electron-donating N-heterocyclic vinyl groups onto main-group elements (E): halosilane elimination and base-induced E−C bond formation. Placement of two NHC=CH− ligands (NHC=N-heterocyclic carbene) onto a GeII center affords a two-coordinate germylene, a heavy congener of the elusive divinyl carbenes. The π-donating ability of this vinylic ligand scaffold was further demonstrated by the synthesis of a three-coordinate germylium cation R3Ge+. [ABSTRACT FROM AUTHOR]

Different reactions of Mes* substituted phosphanes (Mes* = 2,4,6-tri-tert-butylphenyl) led to the formation of the bicyclic tetraphosphane Mes*P4Mes* (5) and its unknown Lewis acid adduct 5·GaCl3. In this context, the endo–exo isomer of 5 was fully characterized for the first time. The synthesis was achieved by reactions involving “self-assembly” of the P4 scaffold from P1 building blocks (i.e. primary phosphanes) or by reactions starting from P2 or P4 scaffolds (i.e. a diphosphene or cyclic tetraphosphane). Furthermore, interconversion between the exo–exo and endo–exo isomer were studied by 31P NMR spectroscopy. All compounds were fully characterized by experimental as well as computational methods. [ABSTRACT FROM AUTHOR]

The linkage of an imidazole-based N-heterocyclic olefin (NHO), containing a terminal CH2 donor group, with a phosphorus-centered diradical molecular fragment leads to an open-shell singlet diphospha-indenylide system, a new class of P-heterocycles, which can be interpreted both as a phosphorus-centered diradicaloid and as a zwitterion with a permanent, overall charge separation between the N- and P-heterocyclic ring systems. The rotation of the imidazole ring, which is thermally possible due to a central C-C bond with a weakened π-component, changes both the charge separation and diradical character depending on the dihedral angle, as quantum mechanical calculations indicate. By varying the bulkiness of substituents at the imidazole-based NHO, it was possible to obtain different diphospha-indenylide species with different rotation angles in the solid state and hence varying diradical character. Imidazolium-diphospha-indenyli-des represent a new class of NHO-based zwitterions with diradical character. Their synthesis, structure, and activation chemistry are described, as well as the quantum mechanical description of the electronic structure in these unusual heterocycles. In addition, along the synthesis route to diphospha-indenylide, we also succeeded in isolating a highly reactive monoradical anion, which was also fully characterized., (© 2025 Wiley‐VCH GmbH.)

Atomically precise nanoclusters hold promise for supramolecular assembly and (opto)electronic- as well as magnetic materials. Herein, this work reports that treating palladium(0) precursors with a triphosphirane affords strongly colored Pd 8 (PDip) 6 that is fully characterized by mass spectrometry, heteronuclear and Cross-Polarization Magic-Angle Spinning (CP-MAS) NMR-, infrared (IR), UV-vis, and X-ray photoelectron (XP) spectroscopies, single-crystal X-Ray diffraction (sc-XRD), mass spectrometry, and cyclovoltammetry (CV). This coordinatively unsaturated 104-electron Pd(0) cluster features a cubic Pd 8 -core, µ 4 -capping phosphinidene ligands, and is air-stable. Quantum chemical calculations provide insight to the cluster's electronic structure and suggest 5s/4d orbital mixing as well as minor Pd─P covalency. Trapping experiments reveal that cluster growth proceeds via insertion of Pd(0) into the triphosphirane. The unsaturated cluster senses ethylene and binds isocyanides, which triggers the rearrangement to a tetrahedral structure with a reduced frontier orbital energy gap. These experiments demonstrate facile cluster manipulation and highlight non-destructive cluster rearrangement as is required for supramolecular assembly., (© 2024 The Authors. Advanced Science published by Wiley‐VCH GmbH.)

Dipnictenes of the type RE=ER (E=P, As, Sb, Bi) are the isovalence electronic heavier analogs of alkenes. Although diphosphenes and dipnictenes in general show a variety of binding modes in metal complexes, little is known about haptotropic shift reactions involving these ligands. Herein, we report an unprecedented η 2 to η 1 rearrangement of the dipnictene ligands in titanocene complexes of the type Cp 2 Ti(Pn 2 Ar 2 ) (Pn=P, As; Ar=2,4,6-Me 3 -C 6 H 2 , Mes; 2,6-iPr 2 -C 6 H 3 , Dip; 2,4,6-iPr 3 -C 6 H 2 , Tip), initiated by Lewis basic ligands (L=MeCN, PMe 3 , AdNC, CO). In the presence of L the dipnictene ligand changes its hapticity from η 2 to η 1 and complexes of the general form Cp 2 Ti(L)(Pn 2 Ar 2 ) with a succinctly different electronic structure are obtained. Electronically, the new complexes are best described as biradicaloids with antiferromagnetically coupled (via a π-bond) [Cp 2 Ti III ]⋅ + and [Pn 2 Ar 2 ]⋅ - fragments. However, the biradical character of these systems is affected by the electronic features of the co-ligand and significantly decreases moving from PMe 3 /MeCN (σ-donors) to CNAd/CO (σ-donors/π-acceptors)., (© 2024 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

NHC-phosphinidene (NHCP) adducts are an emerging class of ligands with proven binding ability for main group and transition metal elements. They possess electron-rich P atoms with two lone pairs (LPs) of electrons, making them interesting platforms for the formation of multimetallic complexes. We describe herein a modular, high-yielding synthesis of bis(NHCP)s, starting from alkylidene-bridged bis(NHC)s ((IMe) 2 C n H 2n ; n = 1,3) and triphosphirane (PDip) 3 (Dip = 2,6- i Pr 2 C 6 H 3 ) as phosphinidene transfer reagent. The coordination chemistry of [{DipP(IMe)} 2 CH 2 ], 1 , was studied in detail, and complexes [ 1 ·FeBr 2 ] and [ 1 ·Rh(cod)]Cl were prepared, showing that the ligand has a flexible bite angle. The dicarbonyl complex [ 1 ·Rh(CO) 2 ]Cl, with an average value for the CO stretching frequency of 2029 cm -1 , indicates a strongly donating ligand when compared to related complexes. The binding ability of the remaining two phosphorus LPs was demonstrated with AuCl(SMe 2 ), giving the heterotrimetallic complex [ 1 ·(AuCl) 2 ·Rh(cod)]Cl. Moreover, [ 1 ·Rh(cod)]X (X - = Cl, B(3,5-(CF 3 ) 2 -C 6 H 3 ) 4 ) was tested in the catalytic hydrogenation of methyl- Z -α-acetamidocinnamate (MAC) and dimethyl itaconate (ItMe 2 ), revealing that the chloride complex was inactive, while the BAr F complex demonstrated moderate activity. Additionally, [ 1 ·Rh(cod)]Cl was shown to be moderately air- and moisture-stable, slowly decomposing to the corresponding NHC-stabilized bis-dioxophosphorane, which was independently synthesized by treating the free ligand with dry O 2 .

Heterocycles containing group 13 and 15 elements such as borazines are an integral part of organic, biomedical and materials chemistry. Surprisingly, heterocycles containing P and Al are rare. We have now utilized phosphaalumenes in reactions with alkynes, alkenes and conjugated double bond systems. With sterically demanding alkynes 1,2-phosphaalumetes were afforded, whereas the reaction with HCCH or HCCSiMe 3 gave 1,4-phosphaaluminabarrelenes. Using styrene saturated 1,2-phosphaalumates were formed, which reacted further with additional styrene to give different regio-isomers of 1,4-aluminaphosphorinanes. Using ethylene, a 1,4-aluminaphosphorinane is obtained, while with 1,3-butadiene a bicyclic system containing an aluminacyclopentane and a phosphirane unit was synthesized. The experimental work is supported by theoretical studies to shed light on the mechanism governing the formation of these heterocycles., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

In here we present the deoxygenation of the chalcogen oxides EO 2 (E = S, Se) with R-P(PMe 3 ), so-called phospha-Wittig reagents. The reaction of DABSO (DABCO·2SO 2 ) with R-P(PMe 3 ) (R = Mes*, 2,4,6- t Bu 3 -C 6 H 2 ; Mes Ter, 2,6-(2,4,6-Me 3 -C 6 H 2 ) 2 -C 6 H 3 ) resulted in the formation of thiadiphosphiranes (RP) 2 S (1:R), while selenadiphosphiranes (RP) 2 Se (2:R) were afforded with SeO 2 , both accompanied by the formation of OPMe 3 . Utilizing the sterically more encumbered Dip Ter-P(PMe 3 ) ( Dip Ter = 2,6-(2,6-iPr 2 -C 6 H 3 ) 2 -C 6 H 3 ) a different selectivity was observed and ( Dip TerP) 2 Se (2:DipTer) along with [Se(μ-P Dip Ter)] 2 (3:DipTer) were isolated as the Se-containing species in the reaction with SeO 2 . Interestingly, the reaction with DABSO (or with equimolar ratios of SeO 2 at elevated temperatures) gave rise to the formation of the OPMe 3 -stabilized dioxophosphorane (phosphinidene dioxide) Dip TerP(O) 2 -OPMe 3 (4:DipTer) as the main product. This contrasting reactivity can be rationalized by two potential pathways in the reaction with EO 2 : (i) a Wittig-type pathway and (ii) a pathway involving oxygenation of the phospha-Wittig reagents and release of SO. Thus, phospha-Wittig reagents are shown to be useful synthetic tools for the metal-free deoxygenation of EO 2 (E = S, Se).

N-containing molecules are mostly derived from ammonia (NH 3 ). Ammonia activation has been demonstrated for single transition metal centers as well as for low-valent main group species. Phosphinidenes, mono-valent phosphorus species, can be stabilized by phosphines, giving so-called phosphanylidenephosphoranes of the type RP(PR' 3 ). We demonstrate the facile, metal-free NH 3 activation using ArP(PMe 3 ), affording for the first time isolable secondary aminophosphines ArP(H)NH 2 . DFT studies reveal that two molecules of NH 3 act in concert to facilitate an NH 3 for PMe 3 exchange. Furthermore, H 2 NR and HNR 2 activation is demonstrated., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

No metal needed: Boron does the job! The activation of the inert dinitrogen molecule has fascinated chemists for ages. In a ground-breaking study Braunschweig and co-workers have now demonstrated that N 2 activation can be achieved with the aid of the p-block element boron-a reactivity previously restricted to transition metals., (© 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Donor-acceptor complexes of the oxoboranes ClB=O and HOB=O were synthesized and each feature short multiply bonded B=O linkages. The retention of high Lewis acidic character within these encapsulated monomeric oxoboranes was manifested by their ability to support C-F and Si-O bond activation/functionalization. The reported ClB=O complexes can be regarded as synthetic surrogates of the [BO] + cation, an inorganic analogue of CO., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Different reactions of Mes* substituted phosphanes (Mes* = 2,4,6-tri-tert-butylphenyl) led to the formation of the bicyclic tetraphosphane Mes*P4Mes* (5) and its unknown Lewis acid adduct 5·GaCl3. In this context, the endo-exo isomer of 5 was fully characterized for the first time. The synthesis was achieved by reactions involving "self-assembly" of the P4 scaffold from P1 building blocks (i.e. primary phosphanes) or by reactions starting from P2 or P4 scaffolds (i.e. a diphosphene or cyclic tetraphosphane). Furthermore, interconversion between the exo-exo and endo-exo isomer were studied by (31)P NMR spectroscopy. All compounds were fully characterized by experimental as well as computational methods.

A stable donor-acceptor coordination complex of the elusive parent inorganic iminoborane HBNH (a structural analogue of acetylene) is reported. This species was generated via thermally induced N2 elimination/1,2-H migration from a hydrido(azido)borane adduct NHC⋅BH2N3 (NHC=N-heterocyclic carbene) in the presence of a fluorinated triarylborane. The mechanism of this process was also investigated by computational and isotopic labeling studies. This transformation represents a new and potentially modular route to unsaturated inorganic building blocks for advanced material synthesis., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This work describes the synthesis and full characterization of elusive chloropnictenium ion salts of the type [(R)Ar*N(SiMe)ECl][A] ((R)Ar* = 2,6-(CHPh2)-4-R-C6H2, R = Me, tBu; E = Sb, Bi; A(-) = GaCl4, Al(OCH(CF3)2)4). In these species the cation is significantly stabilized by weak arene interactions to flanking phenyl groups of the (R)Ar* moiety. In this context the bonding situation has been studied by computational means and the reactivity towards the Lewis base 4-dimethylaminopyridine (dmap) was investigated., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)