The first silenolates with exocyclic structures [(Me3Si)2Si(Si2Me4)2SiC(R)O]−K+ (2a: R = 1-adamantyl; 2b: mesityl; 2c: o-tolyl) were synthesized by the reaction of the corresponding acylcyclohexasilanes 1a–c with KOtBu. NMR spectroscopy and single-crystal X-ray diffraction analysis suggest that the aryl-substituted silenolates 2b,c exhibit increased character of functionalized silenes as compared to the alkyl-substituted derivative 2a due to the different coordination of the K+ counterion to the SiC(R)O moiety. 2b,c, thus, reacted with ClSiiPr3 to give the exocyclic silenes (Me3Si)2Si(Si2Me4)2Si=C(OSiiPr3)R (3b: R = Mes; 3c: o-Tol), while 2a afforded the Si-silylated acylcyclohexasilane 1d. The thermally remarkably stable compound 3b, which is the first isolated silene with the sp2 silicon atom incorporated into a cyclopolysilane framework, could be fully characterized structurally and spectroscopically.

Large enterprise resource planning (ERP) programs and their critical success factors (CSFs) have been subject to intensive research in recent years. One of the key challenges is their complexity in terms of their duration, context, and social dynamics. The aim of this study is to investigate these matters with the help of an interpretative case study using the coding techniques of the grounded theory method. We

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The factors affecting the stabilization of diphosphastannylenes, such as substituent size, steric demand, and type of substituent (aryl, alkyl, silyl) were investigated via a comprehensive DFT and experimental investigation. The influence of various substituents (H, Me, t Bu, Ph, TMS, Hyp = (Si(SiMe 3 ) 3 )) on the pyramidalization of the phosphorus centers and cone angle determination of those substituents were carried out. Through these considerations, ligand systems capable of isolating a stable Sn(II) species were determined. Synthetic work led to the isolation of dimeric supermesityl(trimethylsily)phosphanides, 2,4,6-tris(t-butyl)phenyl trimethylsilyl lithium phosphanide, 2,4,6-tris(t-butyl)phenyl trimethylsilyl potassium phosphanide, and one hypersilylphosphanide [HypP(SiMe 3 )-K•DME]. In addition to that, a novel monomeric diphosphastannylene [HypP(SiMe 3 )] 2 Sn was isolated as well as confirmed by experimental and calculated NMR data and single crystal X-ray analysis.