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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 Pd8(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 Pd8‐core, µ4‐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. [ABSTRACT FROM AUTHOR]

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Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Phosphaalumenes are the heavier isoelectronic analogs of alkynes and have eluded facile synthesis until recently. We have reported that the combination of a phosphinidene transfer agent, ArTerP(PMe3) (ArTer=2,6‐Ar2‐C6H3), with (Cp*Al)4 (Cp*=C5(CH3)5) afforded the phosphaalumenes ArTerPAlCp* as isolable, violet, thermally stable compounds. In here we describe attempts to utilize Mes*P(PMe3) (Mes*=2,4,6‐tBu3‐C6H2) as a phosphinidene source in combination with different Al(I) precursors, namely DipNacnacAl (DipNacnac=HC[C(Me)NDip]2, Dip=2,6‐iPr2‐C6H3), (Cp*Al)4 and Cp3tAl (Cp3t=1,2,4‐tBu3‐C5H2). In all cases the formation of phosphaalumenes was not observed, however, their intermediate formation is indicated by formation of the dimer [Cp*Al(μ‐PMes*)]2 (2) and C−H‐bond activation products along the putative P=Al bond, giving unusual 1,2‐P,Al‐tetrahydronaphtalene derivatives 1 and 4, clearly underlining the role the sterically demanding group on phosphorus plays in these transformations. The reactivity studies are supported by theoretical studies, demonstrating a thermodynamic preference for the C−H activation products. Additionally, we show that there are potential pitfalls in the synthesis of Cp*2AlH, the precursor to make (Cp*Al)4 and give recommendations how to circumvent these. [ABSTRACT FROM AUTHOR]

Primary and secondary amines selectively react with the lactone moiety of γ-valerolactone oxide (GVLO). Several primary amines afforded the resulting epoxyamides with an intact epoxy group. In some cases addition of two equivalents of amine resulted in additional epoxide opening to give α,γ-dihydroxy-β-amino-amides. The selective lactone-opening in GVLO was further corroborated by DFT-studies. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In here we present the deoxygenation of the chalcogen oxides EO2 (E = S, Se) with R-P(PMe3), so-called phospha-Wittig reagents. The reaction of DABSO (DABCO·2SO2) with R-P(PMe3) (R = Mes*, 2,4,6-tBu3-C6H2; MesTer, 2,6-(2,4,6-Me3-C6H2)2-C6H3) resulted in the formation of thiadiphosphiranes (RP)2S (1:R), while selenadiphosphiranes (RP)2Se (2:R) were afforded with SeO2, both accompanied by the formation of OPMe3. Utilizing the sterically more encumbered DipTer-P(PMe3) (DipTer = 2,6-(2,6-iPr2-C6H3)2-C6H3) a different selectivity was observed and (DipTerP)2Se (2:DipTer) along with [Se(μ-PDipTer)]2 (3:DipTer) were isolated as the Se-containing species in the reaction with SeO2. Interestingly, the reaction with DABSO (or with equimolar ratios of SeO2 at elevated temperatures) gave rise to the formation of the OPMe3-stabilized dioxophosphorane (phosphinidene dioxide) DipTerP(O)2-OPMe3 (4:DipTer) as the main product. This contrasting reactivity can be rationalized by two potential pathways in the reaction with EO2: (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 EO2 (E = S, Se). [ABSTRACT FROM AUTHOR]

The phospha–Wittig reagent MesTerPPMe3 (MesTer = 2,6-{2,4,6-Me3–C6H2}–C6H3) and arsa–Wittig reagent DipTerAsPMe3 (DipTer = 2,6-{2,6-iPr2-C6H3}–C6H3) have been employed to synthesize the titanocene complexes Cp2Ti(PMe3)PnAr (Pn = P, As) with terminal phosphinidene or arsinidene ligands, respectively. Ab initio studies show that the description as singlet biradicaloids in their ground state is warranted. [ABSTRACT FROM AUTHOR]

This Minireview outlines the synthesis and reactivity of homoleptic, cyclic oligophosphanes, which have been known for more than 150 years. We will discuss a variety of (PR)n (n = 3,4,5,6) species and outline approaches towards their syntheses in the first part of this review. Then the unique reactivity of these inorganic ring systems will be discussed in detail with a focus on recent findings within the last 20 years. First ring expansion reactions will be described, which are mainly restricted to cyclotriphosphanes. Secondly, ring fragmentation will be highlighted, including phosphinidene transfer reactions. Furthermore, cyclooligophosphanes can be functionalized while retaining the parent ring structures. As oligophosphanes offer multiple donor sites, in a last part the coordination chemistry of these species is highlighted. We hope that this Minireview will spark further interest in this underexplored class of compounds as reagents in inorganic and organic synthesis, as well as the design of new P‐containing materials. [ABSTRACT FROM AUTHOR]