Synthesis and Spectroscopic Studies of Arylethynylsilanes

Chemical Bonding and Activity of Atomically Dispersed Silicon in Two- and Three-Dimensional Materials

On the basis of the especially tunable electronic property of Si, several kinds of nanomaterials with atomically dispersed Si were constructed and characterized by extensive first-principles calculations and ab initio molecular dynamics (AIMD) simulations. The new-type Si(X≡Y)n wide-bandgap semiconductors featuring through-space d-π* hyperconjugation exhibit unique properties in photoelectric conversion, photoconductivity, structural mechanics, etc. The SiC8 siligraphene with the planar tetracoordinate Si (ptSi) has a high lithium-storage capacity and comparably facile surface migration behaviors of both Li and Li+, making it a promising anode material for high-performance Li-ion batteries. The atomically dispersed Si sites of 2D monolayer materials, such as ptSi and three- and four-coordinated Si atoms, generally exhibit remarkable catalytic activity toward CO2 activation with different electron mechanisms, resulting in different scaling relations between the activity and the p-band center. The computational findings enrich the understanding of structural and chemical properties of silicon and open up avenues for developing Si-based functional materials.

Si(C≡C)4-Based Single-Crystalline Semiconductor: Diamond-like Superlight and Superflexible Wide-Bandgap Material for the UV Photoconductive Device

A wide-bandgap SiC4 semiconductor with low density and high elasticity has been designed and characterized by ab initio molecular dynamics simulations and first-principles calculations. The through-space conjugation among the d orbitals of Si and the π* orbitals of ethynyl moieties can remarkably enhance the photoconductivity. This new-type superlight and superflexible semiconductor is predicted to have unique electronic, optical, and mechanical properties, and it is a quite promising material for the high-performance UV optoelectronic devices suitable for various practical demands in a complex environment.

Fourfold Diels-Alder reaction of tetraethynylsilane

A series of ethynylated silanes, including tetraethynylsilane, was treated with tetraphenylcyclopentadienone at 300 °C under microwave irradiation to give the aromatized Diels-Alder adducts as sterically encumbered mini-dendrimers with up to 20 benzene rings. The sterically most congested adducts display red-shifted emission through intramolecular π-π interactions in the excited state.

Synthesis and structure of tetraethynylsilane and its silylated derivatives

The known tetrakis((trimethylsilyl)ethynyl)silane was prepared and deprotected. By using trifluoromethanesulfonic acid, the smooth stepwise desilylation of the starting material was achieved, and all of the partially protected and the fully deprotected species were isolated by sublimation. Crystal structures of all of the partially and the fully deprotected species were obtained. None of the compounds is thermally sensitive. Attempts to explosively decompose these species upon heating failed.

Synthesis and photoactivated insecticidal activity of tetraethynylsilanes

A series of tetraethynylsilanes (TETS) have been synthesized by reaction of silicon tetrachloride (SiCl(4)) with Ar-C triple bond CLi, which was prepared in situ by treatment of Ar-C triple bond CH with n-BuLi. For these TETS thus prepared, their photoactivated insecticidal activities against the 4th-instar larvae of Aedes albopictus (Skuse) were evaluated to enrich the structure-activity relationship. In particular, compound 8 exhibited excellent photoactivated insecticidal activity, the LC(50) value was 0.1346 mg L(-1) under UV light treatment and the irradiation-generated enhancement in the activity was more than 69.58-fold, thus could be exploitable as ideal analog candidates in the search for new photoactivated insecticide leads.