Synthesis and characterization of new polyfluorinated dendrimeric phthalocyanines

The synthesis of new polyfluorinated dendrimeric metallophthalocyanines (M = Zn, Ni, Co) bearing 3,5-bis(2′,3′,4′,5′,6′-pentafluorobenzyloxy)benzyloxy moieties (2–4) was achieved by cyclotetramerization of phthalonitrile derivative 1 in the presence of zinc, nickel or cobalt salts in DMF. All the target phthalocyanines were separated by column chromatography and their spectroscopic, fluorescence and energy transfer properties, and aggregation behavior were investigated in different solvents and at different concentrations in chloroform. The compounds were characterized by Fourier transform-infrared, fluorine, proton and carbon nuclear magnetic resonance, mass, ultraviolet–visible and fluorescence spectral data. The phthalocyanines (2–4) were extremely soluble in various organic solvents, such as tetrahydrofuran, acetone and dichloromethane.     

Convenient Synthesis of Bis(indol)alkanes by Niobium(V) Chloride

Bis(indolyl)alkanes have been synthesized in excellent yields in the presence of a catalytic amount of niobium(V) chloride under solvent-free conditions.     

微波辐射下双(2-苯并咪唑基)烷烃的合成

微波辐射条件下合成了7种双（2－苯并咪唑基）烷烃,为这类化合物的合成提供了一种新方法,相比于常规反应,反应时间大为缩短且产率相当。     

Synthesis and characterization of poly[phenyl(fluoroalkyloxaalkane)silanediyl]s

Monomeric fluoroalkoxyalkyl(phenyl)dichlorosilanes were synthesized with quantitative yields by hydrosilylation of allyl ethers of fluoroalcohols with phenyldichlorosilane with Pt(Ph₃Sb)₂Cl₂ complex as a catalyst. Starting from these monomers, corresponding polysilanes with weight‐average molecular weights of 2–3 × 10⁴ were obtained by the Wurtz reaction. Increasing the CF₂ groups containing two to six monomer units caused the char yields to increase from 3 to 48% at 800 °C in air. The emission characteristics of these polysilanes in a chloroform solution were examined. They had a narrow peak at 344 nm with a small Stokes shift (≈20 nm). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3761–3767, 2003     

Synthesis of 1,3-Bis-(boryl)alkanes through Boronic Ester Induced Consecutive Double 1,2-Migration

A general and efficient approach for the preparation of 1,3-bis-(boryl)alkanes is introduced. It is shown that readily generated vinylboron ate complexes react with commercially available ICH₂Bpin to valuable 1,3-bis-(boryl)alkanes. The introduced transformation, which is experimentally easy to conduct, shows broad substrate scope and high functional-group tolerance. Mechanistic studies reveal that the reaction does not proceed via radical intermediates. Instead, an unprecedented boronic ester induced sequential bis-1,2-migration cascade is suggested.     

Convenient synthesis of bis(indolyl)alkanes and bis(pyrrolyl)alkanes by Cu(OTf)2-catalyzed addition of indole and pyrrole to acetylenic sulfone

Sulfonyl-containing bis(indolyl)alkanes and bis(pyrrolyl)alkanes were synthesized conveniently by Cu(OTf)₂-catalyzed double Michael addition of indole and pyrrole to acetylenic sulfone.     

Synthesis of 2,3-bis(perfluoroalkyl)quinoxalines and 2,3-bis(perfluoroalkyl)-1,4-benzoxazines from oxides of internal perfluoroolefins

The reactions of oxides of internal trans-, cis-perfluoroolefins with o-phenylenediamine and 2-aminophenol in dioxane gave 2,3-bis(perfluoroalkyl)quinoxalines and 2,3-bis(perfluoroalkyl)-2H-1,4-benzoxazin-2-ols respectively in yields of 23-67%. When N,N-dimethylacetamide was used as a solvent an anionic isomerization of the oxides into ketones, which further yielded 2-(perfluoroalkyl)benzimidazoles in the case of o-phenylenediamine and 2-hydroxy-N-perfluoroalkanoylanilines in the case of 2-aminophenol, became the main path of these reactions. Unusual cyclization resulting in 2-pentafluoroethyl-2-pentafluoropropanoylbenzoxazolidine occurs on interaction between dodecafluoro-3,4-epoxyhexane and 2-aminophenol in N,N-dimethylacetamide.     

Efficient Synthesis of Bis(4-Dimethaminophenyl)arylmethanes and Bis(4-Diamethaminophenyl)alkanes Using Iodine Reagent

A novel synthetic utility of NaICl₂ for the preparation of bis(4-dimethaminophenyl)arylmethanes and bis(4-dimethaminophenyl)alkanes is described. In the presence of an aqueous solution of NaICl₂, the reaction of arenes with aromatic aldehydes gives corresponding triarylmethane derivatives regioselectively in moderate to good yields. The method is also useful for the preparation of diarylalkane derivatives by using aliphatic aldehydes.

Supplemental materials are available for this article. Go to the publisher's online edition of Synthetic Communications ^® to view the free supplemental file.     

Synthesis of bis(glycosylamino)alkanes and bis(glycosylamino)arenes

The condensation of D-mannose and D-galactose with aliphatic and aromatic diamines afforded a series of bis(glycosylamino)alkanes and-arenes. A possible mechanism was proposed for the formation of 1,2-bis(β-D-glycosylamino)benzenes. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2793–2801, December, 2005.     

无溶剂条件下碘催化不对称双吲哚的合成

在室温以及无溶剂条件下,吲哚与烷基-3-吲哚基甲醇在碘的催化下以73％～99％的高收率得到不对称双吲哚烷基化合物。其结构经^1H NMR,IR及MS表征。     

Synthesis and Characterization of Bis(Isopropenylphenoxy)Alkanes and Bis(Vinylphenoxy)Alkanes: Two Classes of Highly Reactive,Photopolymerizable Monomers

Abstract

A novel and facile synthesis of difunctional, aromatic vinyl ether analogs is reported. These materials, which are conveniently prepared by the condensation of 4-acetoxystyrene or 4-isopropenylphenyl acetate with α, ω-dihaloalkanes in the presence of base, can be cationically polymerized using diaryliodonium or triarylsulfonium salts as photoinitiators to produce crosslinked polymers. Relative reactivities of the monomers toward cationic polymerization were studied using differential scanning photocalorimetry. The thermal stabilities of the polymers resulting from the photopolymerization of the difunctional, aromatic vinyl ether analogs were studied using thermogravimetric analysis.     

NaBF4催化合成二吲哚甲烷类化合物

在乙醇水溶液中,以Na BF4为催化剂,通过吲哚与芳香醛间的串联反应合成了二吲哚甲烷衍生物。考察了催化剂种类、反应介质、温度、反应时间等因素对反应的影响,在优化条件下以较高产率得到了一系列目标产物。     

Approaches to the Synthesis of Dicarboxylic Derivatives of Bis(pyrazol-1-yl)alkanes

Carboxylation of bis(pyrazol-1-yl)alkanes by oxalyl chloride was studied. It was found that 4,4′-dicarboxylic derivatives of substrates with electron-donating methyl groups and short linkers (from one to three methylene groups) can be prepared using this method. Longer linkers lead to significantly lower product yields, which is probably due to instability of the intermediate acid chlorides that are initially formed in the reaction with oxalyl chloride. Thus, bis(pyrazol-1-yl)methane gave only monocarboxylic derivative even with a large excess of oxalyl chloride and prolonged reaction duration. An alternative approach involves the reaction of ethyl 4-pyrazolecarboxylates with dibromoalkanes in a superbasic medium (potassium hydroxide–dimethyl sulfoxide) and is suitable for the preparation of bis(4-carboxypyrazol-1-yl)alkanes with both short and long linkers independent of substitution in positions 3 and 5 of pyrazole rings. The obtained dicarboxylic acids are interesting as potential building blocks for metal-organic frameworks.     

Synthesis of tetrakis(2-pyridyl)methane: the first tetrapyridylmethane

Tetrakis(2-pyridyl)methane has been synthesized as the first member of tetrapyridylmethane family by nucleophilic aromatic substitution of 2-chloropyridine with tris(2-pyridyl)methyl anion in refluxing aromatic hydrocarbons; the use of 2-bromopyridine resulted in electron transfer giving rearranged dimer of tris(2-pyridyl)methyl radical.     

Synthesis of bifunctional tetrakis(trimethylsilyl)silane derivatives

Bifunctional derivatives (XMe₂Si)₂Si(SiMe₃)₂ (X = H, Cl, or OH) were synthesized for the first time by the reaction of tetrakis(trimethylsilyl)silane with SbCl₅. The molecular and crystal structure of bis(hydroxydimethylsilyl)bis(trimethylsilyl)silane was established by X-ray diffraction. The fragmentation of the resulting compounds under electron impact was studied by mass spectrometry. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 461–466, March, 2006.     

Synthesis of 1,3‐Bis‐(boryl)alkanes through Boronic Ester Induced Consecutive Double 1,2‐Migration

A general and efficient approach for the preparation of 1,3‐bis‐(boryl)alkanes is introduced. It is shown that readily generated vinylboron ate complexes react with commercially available ICH₂Bpin to valuable 1,3‐bis‐(boryl)alkanes. The introduced transformation, which is experimentally easy to conduct, shows broad substrate scope and high functional‐group tolerance. Mechanistic studies reveal that the reaction does not proceed via radical intermediates. Instead, an unprecedented boronic ester induced sequential bis‐1,2‐migration cascade is suggested.     

Synthesis of fluorinated allylic amines: Reaction of 2-(trimethylsilyl)ethyl sulfones and sulfoxides with fluorinated imines

A new synthesis of fluorinated allylamines through the reaction of 2-(trimethylsilyl)ethyl sulfones and sulfoxides (as vinyl anion equivalents) with imines and imino esters has been described. The process includes a TBAF-mediated fragmentation of 2-(trimethylsilyl)ethyl sulfones to afford the desired allylic amines. When the reaction is performed with the corresponding sulfoxides, the fragmentation takes place under the addition conditions, affording the final products in a single step.     

Oxygenation of aromatic substrates over Pd(II) catalysts bearing bis(pyrazol-1-yl)alkanes ligands

Summary Liquid phase oxygenation of 1-tetralin, ethylbenzene, cyclohexane and toluene is describe using four catalyst precursors such as: (CH₂)n(PzR)PdCl₂ (n=1,2; R=H, Me) at T=100°C, P_air= 5.4 atm, substrate/catalyst ratio=100 for 3 h,. It was observed that the type of alkyl bridge between the pyrazolyl ligands has an effect on the catalytic activity.     

Synthesis and Crystal structure of cis—Dichloro—（tetrakis（methylthio）—ethylene）Palladium（Ⅱ）

1 INTRODUCTION Recently much more attention has been paid to palladium bidentate chelate. Such as palladium diphosphino complexes can be used to catalyze crossing-coupling[1] and monocoupling[2]; palladium diamine complexes can be used to catalyze norbornene polymerization[3] and it can also bind to biologically important molecules[4]. Owing to the above reasons, palladium(Ⅱ) complexes with these ligainds are well researched. However, the neutral analogs with derivatives of dithiole are…     

Bis(imino)pyridine palladium(II) complexes: Synthesis, structure and catalytic activity

Bis(imino)pyridine palladium(II) complexes 3-6 were synthesized by two different methods. The structure of complexes 3 and 4 has been confirmed by X-ray structure analysis. The catalytic studies show that bis(imino)pyridine palladium(II) complexes are highly efficient catalysts in the Suzuki-Miyaura reaction and the complex 4 was used to catalyze the synthesis of fluorinated liquid crystalline compounds via Suzuki coupling reaction.