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Using the AlI precursor Cp3tAl in conjunction with triphosphiranes (PAr)3 (Ar=Mes, Dip, Tip) we have succeeded in preparing Lewis base‐free cyclic diphosphadialanes with both the Al and P atoms bearing three substituents. Using the sterically more demanding Dip and Tip substituents the first 1,2‐diphospha‐3,4‐dialuminacyclobutanes were obtained, whereas with Mes substituents [Cp3tAl(μ‐PMes)]2 is formed. This divergent reactivity was corroborated by DFT studies, which indicated the thermodynamic preference for the 1,2‐diphospha‐3,4‐dialuminacyclobutane form for sterically more demanding groups on phosphorus. Using Cp*Al we could extend this concept to the corresponding cyclic diarsadialanes [Cp*Al(μ‐AsAr)]2 (Ar=Dip, Tip) and additionally add the phosphorus variants [Cp*Al(μ‐PAr)]2 (P=Mes, Dip, Tip). The reactivity of one variant [Cp3tAl(μ‐PPh)]2 towards NHCs was tested and resulted in double NHC‐stabilised [Cp3t(IiPr2)Al(μ‐PPh)]2., Pnictaalenes with a pnictogen−aluminium double bond are inherently unstable and prone to dimerization. The synthesis of Lewis‐base‐free dipnictadialenes is revealed. It is shown that depending on the steric profile of the substituents either the alternating [Cp x Al(μ‐PAr)]2 dimers or the head‐to‐head species [ArPnAlCp3t]2 are formed. DFT studies corroborate that the different outcomes are thermodynamically driven.

In der j��hrlich erscheinenden studentischen Zeitschrift "Die junge Mommsen" werden hervorragende und am Institut f��r Geschichtswissenschaften der Humboldt-Universit��t zu Berlin verfasste studentische Haus- und Abschlussarbeiten publiziert und frei zug��nglich gemacht. Zum einen sollen dadurch Studierende freien Zugriff auf Beispielarbeiten erhalten, an denen sie sich beim Schreiben der eigenen Arbeiten orientieren k��nnen. Zum anderen erhalten studentische Autor*innen mit der Zeitschrift die M��glichkeit, erste Erfahrungen im wissenschaftlichen Publizieren zu sammeln. Weder die Zeitschrift noch die einzelnen B��nde legen dabei einen inhaltlichen Schwerpunkt. Im Gegenteil soll im Sinne des Vorbildcharakters eine m��glichst gro��e thematische Vielfalt im Bereich Geschichtswissenschaften erzielt werden., The annual student journal "Die junge Mommsen" publishes outstanding student theses and dissertations written at the History Department of the Humboldt-Universit��t zu Berlin and makes them freely accessible. On the one hand, students should have free access to sample works, which they can use as orientation when writing their own theses. On the other hand, the journal gives the student authors of the journal the opportunity to gain their first experience in scientific publishing. Neither the journal nor the individual volumes focus on a specific topic. On the contrary, the aim is to achieve the greatest possible thematic diversity in the field of historical sciences in the spirit of exemplary character.

In der jährlich erscheinenden studentischen Zeitschrift "Die junge Mommsen" werden hervorragende und am Institut für Geschichtswissenschaften der Humboldt-Universität zu Berlin verfasste studentische Haus- und Abschlussarbeiten publiziert und frei zugänglich gemacht. Zum einen sollen dadurch Studierende freien Zugriff auf Beispielarbeiten erhalten, an denen sie sich beim Schreiben der eigenen Arbeiten orientieren können. Zum anderen erhalten die studentischen Autoren der Beiträge mit der Zeitschrift die Möglichkeit, erste Erfahrungen im Wissenschaftlichen Publizieren zu sammeln. Weder die Zeitschrift noch die Einzelnen Bände legen dabei einen inhaltlichen Schwerpunkt. Im Gegenteil soll im Sinne des Vorbildcharakters eine möglichst große thematische Vielfalt im Bereich Geschichtswissenschaften erzielt werden. The annual student journal "Die junge Mommsen" publishes outstanding student theses and dissertations written at the History Department of the Humboldt-Universität zu Berlin and makes them freely accessible. On the one hand, students should have free access to sample works, which they can use as orientation when writing their own theses. On the other hand, the journal gives the student authors of the journal the opportunity to gain their first experience in scientific publishing. Neither the journal nor the individual volumes focus on a specific topic. On the contrary, the aim is to achieve the greatest possible thematic diversity in the field of historical sciences in the spirit of exemplary character.

The mol­ecular and crystal structure of a formal 20 electron zirconium(IV) complex bearing two cyclo­penta­dienyl and one sterically demanding penta­fulvene ligand is reported in which the penta­fulvene is bound in an η5:η1 manner. The complex crystallizes together with toluene and n-hexane in a ratio of 1:0.125:0.125., The crystal structure of a solvated zirconocene penta­fulvene complex with a bulky adamantyl­idene substitution pattern, namely (η5,η1-adamantyl­idene­penta­fulvene)bis­(η5-cyclo­penta­dien­yl)zirconium(IV)–toluene–n-hexane (8/1/1), [Zr(C15H18)(C5H5)2]·0.125C7H8·0.125C6H14, is reported. Reducing zirconocene dichloride with magnesium results in the formation of a low-valent zirconocene reagent that reacts readily with adamantyl­idene­penta­fulvene to give the aforementioned complex. Single crystal X-ray diffraction proves the dianion-like η5:η1 binding mode of the fulvene ligand to the central ZrIV atom. The asymmetric unit contains four independent mol­ecules of [η5:η1-adamantyl­idene­penta­fulvene]bis­[(η5)-cyclo­penta­dien­yl]zirconium(IV), together with half a mol­ecule of toluene disordered with half a mol­ecule of n-hexane (the solvent mol­ecules have no direct influence on the complex). In each of the four complex mol­ecules, the central ZrIV atom has a distorted tetra­hedral coordination environment. The measured crystal consisted of two domains with a refined ratio of 0.77:0.23.