Preparation of Nano Silica Supported Sodium Hydrogen Sulfate: As an Efficient Catalyst for the Trimethyl,Triethyl and t‐Butyldimethyl Silylations of Aliphatic and Aromatic Alcohols in Solution and under Solvent‐free Conditions

Nano silica supported sodium hydrogen sulfate has been prepared by mixing NaHSO₄ with activated Nano silicagel. We wish to report a new method for the synthesis of trimethyl (TMS), triethyl (TES) and t‐butyldimethyl silyl (TBS) ethers from benzylic, allylic, propargylic alcohols, phenols, naphtholes and some of phenolic drugs in the solution and under solvent‐free conditions.     

Fluorescent cyclopentadithiophene derivatives having phenyl-substituted silyl moieties

4,4-Dimethylcyclopenta[2,1-b:3,4-b′]dithiophene derivatives bearing trimethyl-, dimethylphenyl-, diphenylmethyl-, or triphenyl-silyl moieties were synthesized. The introduction of the silyl moieties onto cyclopenta[2,1-b:3,4-b′]dithiophene induced fluorescent emission as well as the bathochromic shift of wavelength at the maximum absorption and fluorescence. It was found that the larger number of phenyl group on silyl moiety resulted in the higher fluorescence quantum yield.     

Derivatization of Tris(trimethylsilyl)heptaphosphane

Through SiP bond cleavage, the reaction of P₇(SiMe₃)₃ with one equivalent of KO^tBu or LiO^tBu afforded different isomers of the heptaphosphanide anion [P₇(SiMe₃)₂]⁻. With LiO^tBu, concomitant inversion at an equatorial (silylated) phosphorus atom occurred and the C_s symmetric isomer characterized by a mirror plane formed. With KO^tBu, inversion did not occur and the resulting asymmetric anion with C₁ symmetry formed. With NaO^tBu, a mixture of both isomers was obtained. The symmetries and structures of the anions were elucidated with ³¹P{¹H} and ²⁹Si{¹H} NMR spectroscopy, and relative stabilities were calculated employing the B3LYP/6-31+G* method.The reaction of KP₇(SiMe₃)₂ or LiP₇(SiMe₃)₂ with 1,2-dichlorotetramethyldisilane led to (SiMe₃)₂P₇SiMe₂SiMe₂P₇(SiMe₃)₂, a molecule composed of two P₇-cages connected by a disilane bridge. It can also be obtained through silyl exchange using P₇(SiMe₃)₃ and ClMe₂SiSiMe₂Cl. The compound was characterized with ³¹P and ²⁹Si-NMR spectroscopy and elemental analysis. Treatment of P₇(SiMe₃)₃ with HypCl (Hyp = hypersilyl = Si(SiMe₃)₃) in DME led to the quantitative formation of Hyp₂P₇SiMe₃. Single crystal X-ray diffraction as well as ³¹P and ²⁹Si-NMR spectroscopy proves the presence of a heteroleptically substituted heptaphosphane cage.Quantum chemical HF and B3LYP/6-31G* calculations of equilibrium structures for the two possible isomers of P₇(SiMe₃)₃ (sym and asym) reveal that asym is destabilized by about 30-40 kJ mol⁻¹, which explains why its formation could not be observed. The phosphorus inversion barrier for the sym → asym transition is calculated as 60-70 kJ mol⁻¹.     

以幂零李代数R_n为幂零根基的可解李代数(英文)

In this paper we explicitly determine automorphism group of filiform Lie algebra Rn to find the indecomposable solvable Lie algebras with filiform Lie algebra Rn nilradicals.We also prove that the indecomposable solvable Lie algebras with filiform Rn nilradicals is complete.     

Banach代数上的高阶Jordan-triple导子系的广义Hyers-Ulam-Rassias稳定性

针对Banach代数上的高阶Jordan—triple导子系,基于与函数方程有关的广义的Hyers—Ulam-Rassias稳定性的原理．采用线性算子论的方法,结合广义的Jensen等式,证明了Banach代数上与高阶导子系有关的函数方程具有广义的Hyers—Ulam-Rassias稳定性．证明结果表明该方法实用性强,...     

导子交换子幂值的零化子条件

Let R be a prime ring with center Z(R), I a nonzero ideal of R, d a nonzero derivation of R and 0≠a∈ R. In the present paper, our object is to study the situation a[d(xk), xk]n∈ Z(R) for all x ∈ I under certain conditions, where n(≥ 1), k(≥ 1) are fixed integers.     

The Even Part of Finite-Dimensional Modular Lie Superalgebra Г

Let F be the underlying base field of characteristic p ＞ 3 and denote by Γō the even part of the finite-dimensional Lie superalgebra Γ.We give the generator sets of the Lie algebra Γō.Using certain properties of the canonical tori of Γō,we describe explicitly the derivation algebra of Γō.     

无催化剂下醇和酚的高效O-硅基化

硅醚类化合物广泛应用于有机合成、 分离分析和精细化工等领域. 六甲基二氮硅烷是近年来发展的一种新型硅基化试剂, 被用于硅醚的高效合成, 但由于六甲基硅烷较为惰性, 通常需要加入催化剂活化. 本文报道了一种无催化剂下醇、 酚的高效硅基化新方法. 研究结果表明, 该方法可以兼容一级苄醇、 杂芳基苄醇、 脂肪醇, 二级醇甚至三级醇, 多数反应可以实现定量转化, 无需柱层析即可实现产物的分离纯化. 该方法可以拓展到酚的高效硅醚化, 也可以很方便地放大到100 mmol, 收率达到99%, 表明该方法具有较好的实用价值.     

可换环上Abel李代数的全形的导子和自同构

决定了可换环上Abel李代数的全形的导子代数和自同构群.