Conversion of E4 (E4=P4, As4, AsP3) by Ni(0) and Ni(I) Synthons – A Comparative Study

The reactivity of white phosphorus and yellow arsenic towards two different nickel nacnac complexes is investigated. The nickel complexes [(L¹Ni)₂tol] ( 1 , L¹=[{N(C₆H₃ⁱPr₂-2,6)C(Me)}₂CH]⁻) and [K₂][(L¹Ni)₂(μ,η^{1 : 1}-N₂)] ( 6 ) were reacted with P₄, As₄ and the interpnictogen compound AsP₃, respectively, yielding the homobimetallic complexes [(L¹Ni)₂(μ-η²,κ¹:η²,κ¹-E₄)] (E=P ( 2 a ), As ( 2 b ), AsP₃ ( 2 c )), [(L¹Ni)₂(μ,η^{3 : 3}-E₃)] (E=P ( 3 a ), As ( 3 b )) and [K@18-c-6(thf)₂][L¹Ni(η^{1 : 1}-E₄)] (E=P ( 7 a ), As ( 7 b )), respectively. Heating of 2 a , 2 b or 2 c also leads to the formation of 3 a or 3 b . Furthermore, the reactivity of these compounds towards reduction agents was investigated, leading to [K₂][(L¹Ni)₂(μ,η^{2 : 2}-P₄)] ( 4 ) and [K@18-c-6(thf)₃][(L¹Ni)₂(μ,η^{3 : 3}-E₃)] (E=P ( 5 a ), As ( 5 b )), respectively. Compound 4 shows an unusual planarization of the initial Ni₂P₄-prism. All products were comprehensively characterized by crystallographic and spectroscopic methods.     

Hybrid group 15(E15)–group 14(E14) element cationic pyramidal structures E15[E144(SiR3)4]+: A DFT study

Hybrid cationic pyramidanes {E¹⁵[E¹⁴₄R₄]}⁺ (E¹⁵ = P–Bi; E¹⁴ = C–Ge, R = H, SiMe₃) have been studied by the DFT calculations, and their structures, electronic properties and bonding nature are discussed. Square-pyramidal geometry in the real neutral compounds {E¹⁵[E¹⁴₄(SiMe₃)₄]}⁺[AlCl₄]^? is preserved.     

(i-Bu)2Te催化下(2E、4E)-二烯酸酯的高立体选择性合成

Ｗｉｔｔｉｇ型反应是一类具有巨大潜在应用价值的反应。它简化了制备Ｗｉｔｔｉｇ试剂的繁琐过程。在（ｉ－Ｂｕ）２Ｔｅ催化下用δ－溴代巴豆酸酯和醛采用一锅法反应高立体选择性地合成（２Ｅ．４Ｅ）－二烯酸酯是Ｗｉｔｔｉｇ型反应的又一成果。     

Inhibition of Mild Steel Corrosion in 1 M Hydrochloric Acid Using (E)-(4-(4-methoxybenzylideneamino)-4H-1,2,4-triazole-3,5-diyl) Dimethanol (MBATD)

The inhibition of mild steel corrosion in 1 M HCl by (E)-(4-(4-methoxybenzylideneamino)-4H-1, 2,4-triazole-3,5-diyl) dimethanol (MBATD) was investigated by polarization, AC impedance, thermodynamic, molecular dynamics, and quantum chemical studies. Polarization studies revealed that MBATD act as mixed type inhibitor. Adsorption followed the Langmuir mode with a negative value of free energy, which indicates a stable and spontaneous inhibition process. To understand the energy changes associated with various thermodynamic and kinetic processes, different calculations were made. The correlation between inhibitive action and molecular structure is ascertained through quantum chemical calculations. The adsorption behavior of the inhibitor molecule on mild steel surface has been theoretically computed using molecular dynamics and density functional theory.     

Synthesis of 1,7-Bis(4-hydroxyphenyl)hepta-4E,6E-dien-3-one

Diarylheptanoids, most of which appearing in the areas of anti-inflammatory, anti-oxidative, super-oxide scavenging and anti-hepatotoxic effects, constitute a distinct group of metabolites of natural plants characterized by two aromatic rings linked by a linear seven aliphatic chain. We have investigated this kind of compounds and made some progress.[1]1,7-Bis(4-hydroxy-phenyl)hepta-4E,6E-dien-3-one (1) was firstly isolated from the seeds of Alpinia blepharocalyx.[2] So far the synthesis of the compound has not been reported yet. Herein, we report the synthesis of compound 1. The synthetic route is outlined in Scheme 1.     

Synthesis of (E) α,2,4-Trinitrostilbenes from (E) 2,4-Dinitrostilbenes

Abstract

A convenient synthesis of (E) α,2,4-trinitrostilbenes 2a–d from (E) 2,4-dinitrostilbenes la–e by direct nitration is reported. Isomerization of the trans geometry of the reactant stilbenes to cis in the products was found. The structures of stilbenes 2a, 2c and 2d were confirmed by XRD.     

1,3-手性转移反应的研究 (4R)-和(4S)-4-甲基(E)-2-辛烯醇的合成

以手性辛烯二醇双酯与甲基锂铜反应, 经1,3手性转移, 分别生成立体选择性高的(4R)和(4S)-4-甲基-辛烯醇酯。     

1,3-手性转移反应的研究 (4R)-和(4S)-4-甲基(E)-2-辛烯醇的合成

以手性辛烯二醇双酯6和7与甲基锂铜反应,经1,3手性转移,分别生成立体选择性高的(4R)和(4S)-4-甲基-辛烯醇酯8a 和9a     

Diacetylenic Derivatives of Fe2(CO)6(μ-EE′): Spectroscopic Investigations of Fe2(CO)6{μ-EC(H) = C(C≡ CMe)E′} (E = E′, E ≠ E′; E, E′ = S, Se, Te)

The diacetylenic adducts, Fe₂(CO)₆{-EC(H) = C(C CMe)E} (E = E, E E; E, E = S, Se, Te) (1–8) have been obtained from the room temperature stirring of Fe₂(CO)₆(-EE) with HC CC CMe in methanol solvent containing sodium acetate. Compounds 1–8 have been characterized by IR and multinuclear NMR (¹H, ¹³C, ⁷⁷Se, and ^l25Te) spectroscopy. Trends in the chemical shifts of ⁷⁷Se and ¹²⁵Te NMR spectra of Fe₂(CO)₆{-EC(H) = C(C CMe)E} with a variation of EE are discussed.     

Stereoselective Synthesis of (E)-4-Cyano-γ,δ-Unsaturated Nitriles

(E)-4-Cyano-γ,δ-unsaturated nitriles were synthesized from the HMPA promoted sequential transformations of diethyl (cyanomethyl)phosphonate, potassium tert-butoxide, acrylonitrile and aldehydes in 71--83% yield.     

Synthesis and Crystal Structure of (E)-[1-Ferrocenyl-2-(4-Chlorophenyl) ethylene]

1INTRoDUCTIoNCurrently,thereisaconsiderableinterestintheinvestigationoforganicandorganometallicmaterialsshowinglargenonlinearopticalresponse.Theirpotentialusehasbeenresearchedindeviceapplicationswhicharerelatedtothetelecommuni-cations,opticalcomputingandopticalinformationprocessing"2i.Onamicroscopiclevel,oneofthemajorphysicalparameterstodecidethenonlinearopticalpropertiesofmaterialsisthemolecularhyperpolarizability,avaluedeterminedbyelectronicandgeometricstructureofmolecule.Thetitlecompoun…     

SYNTHESES AND CRYSTAL STRUCTURES OF (Et_4N)_2(Fe_2Se_2(SPh)_4) AND (Et_4N)_2(Fe_4Se_4Cl_4)

<正> Since the discovery of iron-sulfur proteins , a number of analogous compounds of the active sites of iron-sulfur proteins has been synthesized and characterized . Due to the similarity between sulfur and selenium, some selenoproteins with similar active site as iron-sulfur proteins were found . We have synthesized a series of iron-selenium compounds in correlative study with the iron-sulfur compounds. In this paper, we will discuss the syntheses and crystal stuctures of the title compounds. The spectroscopic properties of these compounds have been under investigation.     

Rh2(CO)4(μ-Cl)2和Rh4(μ-CO)3(CO)4的简正振动分析

金属簇合物具有独特的结构和成键方式。本文对铑簇合物的简正振动分析进行了研究。通过红外光谱用石蜡油糊涂KBr和聚乙烯窗口, 在Nicolet 200SXV FT-IR光谱上测定了Rh2(CO)4(μ-Cl)2的构型, 并使用分子振动全分析程序MVTA(Basic语言), 在PC机上进行计算。     

Synthesis and Characterisation of New Metallacycles Containing [Ph2P(E)NP(E)Ph2]− (E = S OR Se) Ligands

Abstract

Reaction of [Ph₂P(E)NP(E)Ph₂]^? (E = S or Se) with a series of late transition-metal dimers, in thf or MeOH, leads to facile bridge cleavage and formation of new mononuclear compounds.     

Like (CO)4, Do (CS)4 and (CSe)4 Have a Triplet Ground State?

Cyclobutane‐1,2,3,4‐tetraone, (CO)₄, was computationally predicted and, subsequently, experimentally confirmed to have a triplet ground state, in which a b_2g σ MO and an a_2u π MO were each singly occupied. In contrast, the (U)CCSD(T) calculations reported herein found that cyclobutane‐1,2,3,4‐tetrathione, (CS)₄, and cyclobutane‐1,2,3,4‐tetraselenone, (CSe)₄, both had singlet ground states, in which the b_2g σ MO was doubly occupied and the a_2u π MO was empty. Our calculations showed that both the longer C?X distances and smaller coefficients on the carbon atoms in the b_2g and a_2u MOs of (CS)₄ and (CSe)₄ contributed to the difference between the ground states of these two molecules and the ground state of (CO)₄. An experimental test of the prediction of a singlet ground state for (CS)₄ is proposed.