A Stable Dimer of SiS₂ Arranged between Two Carbene Molecules

Abstract

The Me-cAAC:-stabilized dimer of silicon disulfide (SiS2 ) has been isolated in the molecular form as (Me-cAAC:)2 Si2 S4 (2) at room temperature [Me-cAAC:=cyclic alkyl(amino) carbene]. Compound 2 has been synthesized from the reaction of (Me-cAAC:)2 Si2 with elemental sulfur in a 1:4 molar ratio under oxidative addition. This is the smallest molecular unit of silicon disulfide characterized by X-ray crystallography, electron ionization mass spectrometry, and NMR spectroscopy. Structures with three sulfur atoms arranged around a silicon atom are known; however, 2 is the first structurally characterized silicon-sulfur compound containing one terminal and two bridging sulfur atoms at each silicon atom. Compound 2 shows no decomposition after storing for three months in an inert atmosphere at ambient temperature. The bonding of 2 has been further studied by theoretical calculations.

Cyclic (Alkyl)(amino)carbenes (CAACs): Recent Developments

“…This compound is the silicon analogue of thiophosgene stabilized by a CAAC (Scheme ) . On the other hand, treatment of the bis(CAAC)Si 2 adduct 44 with elemental sulfur or selenium results in the isolation of 50 and 51 , respectively. These two compounds can be regarded as dimers of E=Si=E (E=S or Se) capped by two CAACs, which precludes polymerization and/or decomposition.…”

Cyclische Alkylaminocarbene (CAACs): Neues von guten Bekannten

“…Die Verbindungen 42 und 43 reagieren mit elementarem Schwefel unter Bildung des CAAC→[Si(S)Cl 2 ]‐Addukts 49 , das als ein CAAC‐stabilisiertes Silicium‐Analogon von Thiophosgen angesehen werden kann (Schema ) . Setzt man hingegen das Bis(CAAC)Si 2 ‐Addukt 44 mit elementarem Schwefel oder Selen um, können 50 bzw. 51 isoliert werden, die beide als Dimere einer E=Si=E‐Einheit (E=S oder Se) betrachtet werden können; die Überdachung durch zwei CAACs verhindert die Polymerisation und/oder Zersetzung.…”

A Stable Monomeric SiO2 Complex with Donor–Acceptor Ligands

“…These techniques facilitated synthesis of several stable and easy‐to‐manipulate silanone derivatives . However for silicon dioxides, only the dimer (Si 2 O 4 ) and related heavier analogues (SiS 2 , Si 2 S 4 ) have been isolated as stable complexes with N ‐heterocyclic carbene ligands. Herein, we report the isolation of monomeric silicon dioxide encapsulated within a donor–acceptor ligand system.…”