Neutral 4π-electron tetrasilacyclobutadiene contains unusual features of a Möbius-type aromatic ring.

The search for stable compounds containing an antiaromatic cyclic 4π system is a challenge for inventive chemists that can look back on a long history. Here we report the isolation and characterization of the novel 4π-electron tetrasilacyclobutadiene, an analogue of a 4π neutral cyclobutadiene that exhibits surprising features of a Möbius-type aromatic ring. Reduction of RSiCl (R = (Pr)PCH) with KC in the presence of cycloalkyl amino-carbene (cAAC) led to the formation of corresponding silylene 1.

Amidinato silylene-based inorganic aromatic rings.

Aromaticity is a key concept that underpins the behavior and applications of a wide range of chemical compounds. Its impact on stability, reactivity, biological functions, material properties, and environmental persistence underscores the importance of understanding and harnessing aromaticity in chemistry and materials sciences. We have been pioneers in the field of silylene chemistry and recently, our silylene molecules have been used to synthesize several inorganic aromatic ring compounds.

Phosphasilene mediated CO activation and deoxygenative homo coupling of CO molecules in reactions with metal carbonyls.

Herein, we report the synthesis of a new sterically demanding hyper-coordinate phosphasilene (Mes*PSi(SiMe)(PhC(N Bu)) (1) and its unprecedented reactivity with metal carbonyls (M = Fe, Mo, W). The reaction of 1 with Fe(CO) involves the deoxygenative homocoupling of two CO molecules, forming a rare ketene (μ-CCO) inserted Fe complex 2. Contrastingly, reactions with M(CO) (M = Mo, W) entail the deoxygenated activation of one CO molecule, with the second CO molecule being trapped between Si and P atoms.

Recent progress in transition metal complexes featuring silylene as ligands.

Silylenes, divalent silicon(II) compounds, once considered highly reactive and transient species, are now widely employed as stable synthons in main-group and coordination chemistry for myriad applications. The synthesis of stable silylenes represents a major breakthrough, which led to extensive exploration of silylenes in stabilizing low-valent main-group elements and as versatile ligands in coordination chemistry and catalysis. In recent years, the exploration of transition metal complexes stabilized with silylene ligands has captivated significant research attention.

Preparation of a high-coordinated-silicon-centered spiro-cyclic compound.

Silicon compounds containing silicon-silicon bond with a variety of unusual oxidation states are quite important, because their high reactivity leads to the formation of a variety of silicon compounds. The isolation of such compounds with unusual oxidation states requires a resilient synthetic strategy. Herein, we report the synthesis of a silicon based spirocyclic compound containing a hyper-valent silicon atom and a silicon-silicon bond.