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In this work, the reactivity of tetrel-functionalized phosphorus clusters toward organoazides is probed. Clusters (Me3Si)3P7 (1) and (Me3Ge)3P7 (2) were reacted with benzyl azide, phenyl azide, and 4-bromophenyl azide, and it was found that the [RN] (R = benzyl, phenyl, and 4-bromophenyl) unit from the azide inserted into the phosphorus-tetrel bonds on the cluster, accompanied by N2 elimination. Through control of the azide stoichiometry, the mono-, bis-, and tris-inserted products could be observed, consistent with these insertions proceeding in a stepwise manner. The bonding between the amine moieties and clusters was further investigated by computational chemistry, and the findings were consistent with the phosphorus cluster having undergone a formal oxidation. These insertion reactions are a convenient means of accessing Zintl clusters functionalized with exo-nitrogen-bonded moieties, which, to the best of our knowledge, were previously unknown.

Despite being known for decades the chemical reactivity of homoatomic seven‐atom phosphorus clusters towards small molecules remains largely unexplored. Here, we report that neutral tris(silyl) functionalised heptaphosphane (P7(SiR3)3) cages are capable of heteroallene capture between the P−Si bonds of the cluster. A range of isocyanates and an isothiocyanate were investigated. In the case of isocyanates, silyl bonding at oxygen or nitrogen is regioselectively directed by the functional group on the isocyanate and substituents on the silyl moiety. Above all, we find that captured isothiocyanate molecules can be exchanged for isocyanate molecules, indicative of small molecule catch and release. Small molecule catch and release at these Zintl‐derived clusters reveals their potential application as chemical storage materials or as reusable probes. [ABSTRACT FROM AUTHOR]

"GaOTf" is a simple, convenient source of low-valent gallium for synthetic chemistry and catalysis. However, little is currently known about its composition or reactivity. In this work, 71 Ga NMR spectroscopy shows the presence of [Ga(arene) n ] + salts on oxidation of Ga metal with AgOTf in arene solvents. However, a more complex picture of speciation is uncovered by X-ray diffraction studies. In all cases, mixed-valence compounds containing Ga-arene and Ga-OTf coordination motifs, in addition to an unusual "naked" [Ga] + ion, are found. Addition of 18-crown-6 allows for the isolation of a discrete Ga I crown complex. Evidence of a potential intermediate in the formation of "GaOTf" has been isolated in the form of the bimetallic silver(I)/gallium(I) cluster anion [Ag 4 {Ga(OTf) 3 } 4 (μ-Ga) 6 (OTf) 4 ] 2- ., (© 2020 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)