Density functional theory (DFT) calculations demonstrate that the previously reported reaction of [(BDI)Mg-n-Bu] (BDI = HC{(Me)CN-Dipp} 2 ; Dipp = 2,6-diisopropylphenyl) with the silaborane Me 2 PhSi-Bpin provides the magnesium silanide derivative [(BDI)-MgSiMe 2 Ph], through the intermediacy of a short-lived silyl-pinacolatoorganoborate species. The nucleophilic character of the resultant silanide anion is assayed through a series of reactions with RNCNR (R = i-Pr, Cy, t-Bu) and p-tolNCN-p-tol. When they are performed in a strict 1:1 stoichiometry, all four reactions result in silyl addition to the carbodiimide carbon center and formation of the corresponding β-diketiminato magnesium silaamidinate complexes. Although the performance of the reaction of [(BDI)MgSiMe 2 Ph] with 2 equiv of p-tolylcarbodiimide also results in the formation of a silaamidinate anion, the second equivalent is observed to engage with the nucleophilic γ-methine carbon of the BDI ligand to provide a tripodal diimino-iminoamidate ligand. This behavior is judged to be a consequence of the enhanced electrophilicity of the N-arylsubstituted carbodiimide reagent, a viewpoint supported by a further reaction with the N-isopropyl silaamidinate complex [(BDI)Mg(i-PrN) 2 CSiMe 2 Ph]. This latter reaction not only provides an identical diimino-iminoamidate ligand but also results in 2fold insertion of p-tolNCN-p-tol into a Mg−N bond between the magnesium center and the silaamidinate anion. ■ EXPERIMENTAL SECTIONGeneral Experimental Procedures. All reactions of air-and moisture-sensitive compounds were carried out using standard

Dedicated to Matthias Driess on the occasion of his 60 th birthdayBis(chlorotetrylene)s of Si, Ge, and Sn have been synthetically realized starting from the backbone-bridged bis(amidine) 1. Double deprotonation of 1 and subsequent reaction with trichlorosilane affords the bis(dichorosilane) 2, which is converted to the respective bis(chlorosilylene) 3 by dehydrochlorination using lithium bis(trimethylsilyl)amide. The related bis(chlorogermylene) 4 and the bis(chlorostannylene) 5 are obtained by reacting the dilithium salt with GeCl 2 • (dioxane) and SnCl 2 , respectively. 2 readily reacts with benzil affording the bis(siladioxolene) 6, while no reaction was observed when using the bis(chlorogermylene) 4. The complexes have been fully characterized and their molecular solid-state structures have been investigated by means of single-crystal X-ray diffraction analysis.

The synthesis of 3,4-ethylene-bridged 1,1,2,5-tetrasubstituted biguanides is reported, which are accessible by three alternative routes. Exemplary molecular structures of the ligand and an observed side product have been elucidated by X-ray diffraction analysis. Mono-and dinuclear complexes of the biguanide in both its neutral and monoanionic forms were obtained, including examples of aluminum, copper, magnesium, potassium, tin, and zinc, indicating a versatile coordination behavior, as evidenced by means of single-crystal X-ray diffraction analysis.Article pubs.acs.org/IC

A facile and efficient one‐pot strategy for the preparation of 1,2,3‐tri‐ and 1,1,2,3‐tetrasubstituted bis(guanidine)s by starting from from readily available bis(thiourea)s has been successfully developed. The reaction provides products that contain a range of terminal and bridging groups. After a simple workup procedure, the products were obtained in analytically pure and in good to excellent yields.

Sterically demanding N,N′,N′-substituted 1,2-ethanediamine ligands have been prepared from commercially available starting materials by applying a facile one-step procedure. These ligands offer advantages compared to known systems: a suppressed delocalization due to the saturated backbone inhibits a noninnocent behaviour and the low symmetry of the related metal complexes makes them potential candidates for [a] 965 Scheme 3. Synthesis of the lithium species 4 and of a series of group 13 amidoamine compounds (5-7).Eur. J. Inorg. Chem. 2017, 965-970 www.eurjic.org