Synthesis of a Stable Four-Membered Si₂O₂ Ring and a Dimer with Two Four-Membered Si₂O₂ Rings Bridged by Two Oxygen Atoms, with Five-Coordinate Silicon Atoms in Both Ring Systems

Abstract

The base-stabilized bis-silylene (LSi−SiL, L = PhC(NtBu)2) was reacted with benzophenone in a 1:2 ratio in THF, which afforded a Si2O2 four-membered ring, stabilized by bulky amidinato ligands. The most striking phenomenon is the abstraction of oxygen from benzophenone and the simultaneous formation of a silicon carbon bond. The four-membered Si2O2 ring is planar, and both the silicon atoms are five-coordinate. The two silicon atoms are arranged opposite each other in the four-membered Si2O2 ring. Moreover LSi−SiL was treated with N2O to afford two four-membered Si2O2 rings connected with two oxygen atoms. In this structure also the silicon atoms are five-coordinate.

Reactivity of a Silylsilylene Bearing a Functionalized Diaminochlorosilyl Substituent

“…[6b] Compound 3 was isolated as a highly air-and moisturesensitive colorless crystalline solid in 19 …”

“…[19] Compound 8 was isolated as a highly air-and moisturesensitive colorless crystalline solid, and proved to be soluble in THF and dichloromethane. It is stable in the solid state at room temperature under an inert atmosphere.…”

Synthesis of a Stable Disilyne Bisphosphine Adduct and Its Non‐Metal‐Mediated CO2 Reduction to CO

“…[4] In fact, the chemical properties of the Lewis base stabilized disilynes should be strongly affected by the complexation, and this important issue needs to be addressed. However, compared to transition-metal derivatives, the coordination chemistry of main-group-element species such as disilynes [2][3][4] or silylenes [5] is not very well developed, although their transition-metal-like behavior is of great interest. [6] Thus, although phosphines are ubiquitous ligands in organometallic chemistry, their use in main-groupelement chemistry is not so frequent.…”

Oxidation of Intramolecularly Coordinated Distannyne by S8: From Tin(I) to Tin(IV) Polysulfide Via Tin(II) Sulfide

“…[9] All these results also suggest the general mechanism of two-step oxidation reactions of distannynes, where heavier Group 14 elements are in oxidation state + I. In the course of our systematic studies on the metal-type redox reactivity of alkyne analogues of heavier Group 14 elements, we present here results on the oxidation of the distannyne 1 by S 8 . [10] This reaction, that is the two-step oxidation of a tin(I) center along with complete cleavage of the Sn À Sn bond, produced the organotin(II) sulfide [({2,6-(Me 2 NCH 2 ) 2 C 6 H 3 }Sn) 2 S] (2) in the first step (Scheme 3).…”

“…[7] The redox reaction of [{SiA C H T U N G T R E N N U N G (NtBu) 2 CPh} 2 ] with N 2 O showed the reducing character of the Si I species, and led to the production of the well-defined [R 4 Si 4 O 6 ] compound (R = (NtBu) 2 CPh) with a double-decker structure. [8] A two-step oxidation of the Si I atom according to the route given in Scheme 1 was proposed to explain the formation of this compound.…”