Synthesis of N-[chloro(diorganyl)silyl]anilines

A series of N-[chloro(diorganyl)silyl]anilines RR′Si(NR″Ph)Cl (R, R′ = Me, Ph, CH₂=CH, ClCH₂, Cl(CH₂)₃; R″ = H, Me) was prepared via the reaction of diorganyldichlorosilanes with aniline or N-ethylaniline in the presence of triethylamine.     

μ-氧-双{三[邻氯(氟)苄基]锡}的合成、结构和量子化学研究

The tri(o-chlorobenzyl)tin chloride as well as the tri(o-fluorobenzyl)tin was treated with aqueous solution of NaOH to formed the μ-oxygen-bis[tri(o-chlorobenzyl)tin] and μ-oxygen-bis[tri(o-fluorobenzyl)tin], respectively. The crystal and molecular structures of compound were determined by X-ray diffraction. The crystal(1) belongs to triclinic space group P1 with a=1.0195(5), b=1.0951(6), c=1.0986(6)nm, α=118.250(7), β=104.923(7), γ=99.534(8)°, V=0.9827(9)nm³,Z=1, D_x=1.701g·cm^-3, μ(MoKα)=17.12cm^-1, F(000)=498, R₁=0.0680, wR₂=0.13014. The crystal(2) are triclinic, space group P1 with a=0.9635(3), b=1.0797(4), c=1.0852(3)nm, α =105.807(5), β=90.551(6), γ=116.382(5)°, V=0.9619(6)nm³, Z=2, D_x=1.595g·cm^-3, μ(MoKα)=13.62cm^-1, F(000)=458, R₁=0.0268, wR₂=0.0674. The bond lengths of Sn-C is 0.2128(9)～2.162(12)nm and 0.2155(4)～0.2162(3)nm, and the Sn-O is 0.1901nm and 0.19166(6)nm, respectively. The bond angle Sn-O-Sn is 180.0(0)°. The tin atom has a distorted tetrahedral geometry. The composition characteristics of some frontier molecular orbitals have been investigated by means of G98W package and taking Lanl2dz basis set. (1) CCDC:184751,(2) CCDC:187572.     

The molecular structure of [dimethyl(phenyl)silyl]tris(trimethylsilyl)methane

The structure of the crowded molecule (Me₃Si)₃C(SiMe₂Ph) has been determined by single crystal X-ray diffraction. The steric strain manifest itself mainly in lengthening of the Me₃SiC and Me₂PhSiC bonds (average length 1.920(6) $\text{,ac>A}\text{?}$) and closing up of the CSiC angles within the Me₃Si and Me₂PhSi groups (average 105.2(10)°), with correspondingly large C(1)SiC angles (113.5(13)°; C(1) is the central carbon atom).     

Synthesis of Bis [bis (tert-butylcyclopentadienyl) neodymium chloride] and Structural trend of Bis [bis (tertbutylcyclopentadienyl) lanthanide chloride]

The reaction of NdCl3 with 2 equiv. of Na-ButC5H4 in THF(tetrahydrofuran) gives blue crystals [(ButC5H4)2NdCl]2, C36H52Cl2Nd2 (Mr = 844.11 ), which crystallizes in the triclinic system with space group P-1. The crystal data are a= 11. 978(1), b=12. 671(4), c=12. 706(2)A, α=105.47(2), β=99. 38(1), γ=93. 15(2)°, V=1825(3)A3, Z=2, Dc=1.53g/cm3, F(000)=450, T=298K, λ(MoKα)= 0. 71069 A ,μ= 14. 97cm-1. Final R= 0. 0390, Rw,= 0. 0376 for 4329 reflections with I≥3σ(Io). The molecule has a dimer structure with two certrosymmetrical chlorine bridges. The structural trend of these analogous complexes is discussed.     

Crystal Structure and Antitumor Activity of Tri[2- [N-(4''''-methyl-benzylsulfonyl)amino]ethyl]-amine

1 INTRODUCTION The supramolecular architectures of tripodal ligands with special cavities have attracted much attention of chemists and biochemists because of their interesting structures and possible properties such as ion and molecular recognition, selective inclusion and important biological function[1～5]. However, their potential applications in supra- molecular and biological chemistry for constructing various complexes have not been clearly realized until recent years. Few crystal…     

选择性合成三取代乙氧羰基甲氧基硫杂杯[4]芳烃

对叔丁基硫杂杯[4]芳烃与氯乙酸乙酯在K2CO3/丙酮体系中反应,选择性地合成了三取代乙氧羰基甲氧基硫杂杯[4]芳烃,产率78%,其结构经1H NMR,MS和元素分析表征.     

Crystal Structure and Antitumor Activity of Tri[2-[N-（4′-methyl-benzylsulfonyl）amino]ethyl]-amine

The crystal structure of the title compound (C27H38N4O7S3, Mr = 626.79) has been determined by single-crystal X-ray diffraction. The crystal is of triclinic, space group Pīwith a = 9.411(1), b = 11.645(2), c = 14.672(2) (A。), α = 91.80(1), β = 95.36(1), γ =104.56(1)o, V = 1547.0 (A。)3, Z = 2, Dc = 1.346 g/cm3, λ = 0.71073 (A。), μ(MoKα) = 0.289 mm－1 and F(000) = 664. The structure was refined to R = 0.0406 and wR = 0.1177 for 4103 observed reflections with I > 2σ(I). X-ray diffraction analysis reveals that the title compound is a practically distorted tetrahedron and each molecule contains one lattice H2O by hydrogen bond. The antitumor activity of the title compound against HL-60 human leukemia cells has also been studied by MTT method.     

Remarkable tris(trimethylsilyl)silyl group for diastereoselective [2 + 2] cyclizations

[reaction: see text] Diastereoselective [2 + 2] cyclizations of aldehyde- and ketone-derived silyl enol ethers with acrylates is described. The use of the tris(trimethylsilyl)silyl group allows for unprecedented reactivity, yields, and selectivity for these cyclizations. The presence of silicon-silicon bonds proved to be important for this transformation, where typical silyl groups (TBS and TIPS) failed to give any desired product. The bulky bis(2,6-diphenylphenoxide) aluminum triflimide catalyst was essential for high diastereoselectivity.     

A correction to the molecular structure of [dimethyl(phenyl)silyl]tris(trimethylsilyl)methane

In a recently published structure of (Me₃Si)₃C(SiMe₂Ph) the hydrogen atoms were inadvertently misplaced. The hydrogen atom positions have been redetermined and the structure refinement repeated. There is no significant change in the averaged values for chemically equivalent bond lengths and angles from those previously reported, and the previous conclusions stand.     

μ-氧-双[三(对氟苄基)锡]的合成、表征及晶体结构

The μ-oxygen-bis[tri(p-fluorobenzyl)tin] was synthesized. The structure were characterized by elementary analysis, IR and ¹H NMR and the crystal structure were determined by X-ray single crystal diffraction. The crystal of the title compound belongs to rhombohedral with space group R, a=1.346 4(4), b=1.346 4(4), c=1.772 9(7) nm, α=90°, β=90°, γ=120°, Z=3, V=2.783 2(15) nm³, D_c=1.625 g·cm^-3, μ(Mo Kα)=1.408 mm^-1, S=1.088, F(000)=1 350, R₁=0.027 5, wR₂=0.065 9. In compound, the tin atom has a distorted tetrahedral coordination configuration. CCDC: 257079.     

Synthesis and hydrolytic stability of novel 3-[F]fluoroethoxybis(1-methylethyl)silyl]propanamine-based prosthetic groups

Two new silicon-based prosthetic groups, derived from 3-[ethoxybis(1-methylethyl)silyl]propanamine, have been prepared in good yields. These silicon groups bearing an acid or an azide group were coupled to a model tripeptide (Leu-Gly-Gly) either through a classical amide bond formation or through “click chemistry” via the Huisgen cycloaddition. The radiolabelling with fluorine-18 by substitution of the ethoxy group at silicon has been carried out with success in 51-54% decay corrected radiochemical yields. Radiolabelled peptides were easily prepared by direct ¹⁸F-fluorination of the silicon-bearing tripeptide or by coupling the peptide with a radiolabelled silicon-based prosthetic group. Their stabilities in physiological medium were studied and proved poor.     

Bis[tris(trimethylsilyl)silyl]zink, -cadmium und -quecksilber,schwingungsspektroskopische Daten und Strukturanalysen

Bis[tris(trimethylsilyl)silyl] Zinc, Cadmium, and Mercury – a Structural Study by IR and Raman Spectroscopy and X-Ray Analyses Raman and FT-IR spectra of bis[tris(trimethylsilyl)silyl] zinc ( 1 ), cadmium ( 2 ) and mercury ( 3 ) were recorded. The vibrational data are in agreement with either D_3h or a D_3d symmetry. The latter had been shown to be the correct one at least for the solid state by X-ray diffraction experiments. All three compounds crystallize isomorphically in the triclinic centrosymmetric space group P1 . [ 2 (T = 293 K): a = 9.4388(11); b = 9.744(2); c = 12.926(2); α = 68.200(12); β = 71.971(10); γ = 60.925(10); Z = 1; (T = 173 K): a = 9.336(6); b = 9.585(5); c = 12.488(8); α = 68.77(4); β = 72.28(4); γ = 62.06(4); 3 : a = 9.467(2); b = 9.749(2); c = 12.885(2); α = 67.840(14); β = 71.510(14); γ = 60.890(14); Z = 1]. The Hg—Si bondlength in 3 was found to be 246.9(2)pm, somewhat shorter then in all disilylmercury derivatives investigated sofar and even shorter than the Cd—Si bond in 2 (250.4(1)pm). Bondlengths and angles within the tris(trimethylsilyl)silyl group are virtually equal in all three group 12 derivatives and lie in the expected range.     

Tri(phosphorano)borazinium-Ionen

Tri(phosphorano)borazinium Ions The synthesis, structures, and quantum-chemical calculations of tri(phosphorano)borazinium ions are reported for the first time. [HBNPEt₃]₃³⁺(I^–)₃ ( 6 ) and [H₄B₃(NPEt₃)₃]²⁺(I^–)₂ ( 7 ) originate from iodine acting on the borane adduct at trimethylsilyltriethylphosphoraneimine. With acetonitrile 6 reacts under formation of [{HBNPEt₃}₃CH₃CN]³⁺(I^–)₃ · CH₃CN ( 8 ). While 6 forms an almost planar B₃N₃ six-membered ring with BN distances of 143 pm, which are equivalent to those in borazine molecules, in 7 and 8 one boron atom at a time is sp³ hybridized due to an additional bonding with a hydride ligand and to the adduct formation with acetonitrile, respectively. The quantum-chemical calculations suggest relatively polar B–N bonds.